UCS2112 Data Sheet

UCS2112
USB Dual-Port Power Switch and Current Monitor
Features
Description
• Dual-Port Power Switches:
- 2.9V to 5.5V source voltage range
- 3.0A continuous current per VBUS port with
40 m On resistance per switch
- Independent port power switch enable pins
- DUAL fault ALERT# active drain output pins
- Constant Current or Trip mode current
limiting behaviors
- Undervoltage and overvoltage lockout
- Back-drive, back-voltage protection
- Auto-recovery fault handling with low test
current
- BOOST# logic output to increase DC-DC
converter output under large load conditions
- A_DET# open-drain outputs for device attach
detection per port
• SMBus 2.0/I2C™ Mode Features:
- Eight programmable current limits assignable
to each power switch
- Other SMBus addresses available upon
request
- Block read and block write
• Self-contained current monitoring (no external
sense resistor required)
• Fully programmable per-port charge rationing and
behaviors
• Per-port BC1.2 VBUS Discharge Function
• Wide Operating Temperature Range:
- -40°C to +105°C
• UL recognized and EN/IEC 60950-1 (CB) certified.
The UCS2112 is a dual USB port power switch
configuration which can provide 3.0A continuous
current (3.4A maximum) per VBUS port with precision
overcurrent limiting (OCL), port power switch enables,
auto-recovery fault handling, undervoltage and
overvoltage lockout, back-drive protection and
back-voltage protection, and dynamic thermal
management.
The UCS2112 is well suited for both stand-alone and
applications having SMBus/I2C communications.
For applications with SMBus, the UCS2112 provides
per-port current monitoring and eight programmable
current limits per switch, ranging from 0.53A to 3.0A
continuous current (3.4A maximum). Per-port charge
rationing is also provided ranging from 3.8 mAh to
246.3 Ah.
In Stand-alone mode, the UCS2112 provides eight
current limits for both switches, ranging from
0.53A + 0.53A to 3A + 3A total continuous current
(see Table 1-1).
Both power switches include an independent VBUS discharge function and constant current mode current limiting for BC1.2 applications.
The UCS2112 is available in a 4x4 mm 20-pin QFN
package.
Package Type
ALERT#1
GND
SMDATA
SMCLK
ALERT#2
UCS2112
4x4 QFN*
20
19
18
17
16
15 PWR_EN2
PWR_EN1 1
A_DET#1 2
14 A_DET#2
EP
21
BOOST# 3
13 COMM_ILIM
7
8
9
10
VS
6
VS
11 VBUS2
VDD
VBUS1 5
VS
12 VBUS2
VS
VBUS1 4
* Includes Exposed Thermal Pad (EP); see Table 3-1.
 2015 Microchip Technology Inc.
DS20005424B-page 1
UCS2112
Block Diagram
VBUS
VS
Power
Switch 1
UVLO,
OVLO
VS
VBUS
Power
Switch 2
VBUS
discharge
PWR_EN1
ALERT#1
BOOST#
VDD
A_DET#1
Interface Logic
Temp
Charger
Control,
Measurement,
OCL
PWR_EN2
ALERT#2
A_DET#2
COMM_ILIM
SMCLK
GND
DS20005424B-page 2
SMDATA
 2015 Microchip Technology Inc.
UCS2112
1.0
ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings †
Voltage on VDD, VS, and VBUS pins ...................................................................................................................-0.3 to 6V
Pull-Up Voltage (VPULLUP) ..................................................................................................................... -0.3 to VDD + 0.3
Port Power Switch Current ..................................................................................................................... Internally limited
Voltage on any Other Pin to Ground ...................................................................................................-0.3 to VDD + 0.3V
Current on any Other Pin ..................................................................................................................................... ±10 mA
Package Power Dissipation ........................................................................................................................ See Table 1-1
Operating Ambient Temperature Range .................................................................................................-40°C to +105°C
Storage Temperature Range ..................................................................................................................-55°C to +150°C
† Notice: Stresses above those listed under “Maximum Ratings” may cause permanent damage to the device. This is
a stress rating only and functional operation of the device at those or any other conditions above those indicated in the
operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may
affect device reliability.
TABLE 1-1:
POWER DISSIPATION SUMMARY
De-Rating Factor
TA < +25°C
TA = +70°C
TA = +85°C
Above +25°C
Power Rating Power Rating Power Rating
Package
JC
JA
High K
(Note)
20-pin QFN
4x4 mm
6 °C/W
41 °C/W
24.4 mW/°C
2193 mW
1095 mW
729 mW
Low K
(Note)
20-pin QFN
4x4 mm
6 °C/W
60 °C/W
16.67 mW/°C
1498 mW
748 mW
498 mW
Board
Note:
A High K board uses a thermal via design with the thermal landing soldered to the PCB ground plane with
0.3 mm (12 mil) diameter vias in a 3x3 matrix (9 total) at 0.5 mm (20 mil) pitch. The board is multi-layer with
1-ounce internal power and ground planes and 2-ounce copper traces on top and bottom. A Low K board
is a two layer board without thermal via design with 2-ounce copper traces on the top and bottom.
TABLE 1-2:
ELECTRICAL SPECIFICATIONS
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Symbol
Min.
Typ.
Max.
Unit
Conditions
VDD
4.5
5
5.5
V
Supply Current in Active
(IDD_ACT + IS1_ACT + IS2_ACT)
IACTIVE
—
850
—
µA
Average current IBUS = 0 mA
Supply Current in Sleep
(IDD_SLEEP + IS1_SLEEP +
IS2_SLEEP)
ISLEEP
—
6
20
µA
Average current VPULLUP  VDD
IDETECT
—
200
—
µA
Average current
No portable device attached
(Note 1)
VDD Low Threshold
VDD_TH
—
4
—
V
VDD voltage increasing
VDD Low Hysteresis
VDD_TH_HYST
—
500
—
mV
VDD voltage decreasing
Power and Interrupts - DC
Supply Voltage
Supply Current in Detect
(IDD_DET + IS1_DET + IS2_DET)
Power-on Reset
Note 1:
2:
3:
4:
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
 2015 Microchip Technology Inc.
DS20005424B-page 3
UCS2112
TABLE 1-2:
ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Symbol
Min.
Typ.
Max.
Unit
Conditions
I/O Pins - SMCLK, SMDATA, PWR_EN, ALERT#, A_DET#, BOOST# - DC Parameters
Output Low Voltage
VOL
—
—
0.4
V
ISINK_IO = 8 mA
SMDATA, ALERT#, A_DET#,
BOOST#
Input High Voltage
VIH
2.0
—
—
V
PWR_EN, SMDATA, SMCLK
Input Low Voltage
VIL
—
—
0.8
V
PWR_EN, SMDATA, SMCLK
Leakage Current
ILEAK
—
—
±5
µA
Powered or unpowered
VPULLUP  VDD
TA < 85°C (Note 1)
ALERT# Pin Blanking Time
tBLANK
—
25
—
ms
Blanking time, coming out of
reset
ALERT# Pin Interrupt
Masking Time
tMASK
—
5
—
ms
BOOST# Pin Minimum
Assertion Time
tBOOST_MAT
—
1
—
s
BOOST# Pin Assertion
Current
IBOOST
—
1.9
—
A
Input Capacitance
CIN
—
5
—
pF
Clock Frequency
fSMB
10
—
400
kHz
tSP
—
—
50
ns
tBUF
1.3
—
—
µs
tSU:STA
0.6
—
—
µs
Start Hold Time
tHD:STA
0.6
—
—
µs
Stop Setup Time
tSU:STO
0.6
—
—
µs
Data Hold Time
tHD:DAT
0
—
—
µs
When transmitting to the master
Data Hold Time
tHD:DAT
0.3
—
—
µs
When receiving from the master
Data Setup Time
tSU:DAT
0.6
—
—
µs
Clock Low Period
tLOW
1.3
—
—
µs
Clock High Period
tHIGH
0.6
—
—
µs
Clock / Data Fall Time
tFALL
—
—
300
ns
Min = 20+0.1CLOAD ns
(Note 1)
Clock / Data Rise Time
tRISE
—
—
300
ns
Min = 20+0.1CLOAD ns
(Note 1)
Per bus line (Note 1)
Interrupt Pins - AC Parameters
SMBus/I2C™ Timing
Spike Suppression
Bus Free Time Stop to Start
Start Setup Time
Capacitive Load
Timeout
Idle Reset
Note 1:
2:
3:
4:
CLOAD
—
—
400
pF
tTIMEOUT
25
—
35
ms
Disabled by default (Note 1)
tIDLE_RESET
350
—
—
µs
Disabled by default (Note 1)
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
DS20005424B-page 4
 2015 Microchip Technology Inc.
UCS2112
TABLE 1-2:
ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Symbol
Min.
Typ.
Max.
Unit
Conditions
Port Power Switch
Port Power Switch - DC Parameter
VS_OV
—
6
—
V
Note 2
VS Low Threshold
Overvoltage Lockout
VS_UVLO
—
2.5
—
V
Note 2
VS Low Hysteresis
VS_UVLO_HYST
—
100
—
mV
Note 2
On Resistance
RON_PSW
—
40
—
m
4.75V < VS < 5.25V
VS Leakage Current
ILEAK_VS
—
—
5
µA
Sleep state into VS pin on one
channel (Note 1)
Back-voltage Protection
Threshold
VBV_TH
—
150
—
mV
VBUS > VS
VS > VS_UVLO
IBD_1
—
0
3
µA
VDD < VDD_TH,
Leakage current from VBUS pins
to the VDD and the VS pins
(Note 1)
IBD_2
—
0
2
µA
VDD > VDD_TH,
Leakage current from VBUS pins
to the VDD (in Detect State) or
the VS pins (in Active State)
(Note 1)
ILIM1
—
530
—
mA
ILIM Resistor = 0 or 47 k
(530 mA setting)
ILIM2
—
960
—
mA
ILIM Resistor = 10 k or 56 k
(960 mA setting) (Note 4)
ILIM3
—
1070
—
mA
ILIM Resistor = 12 k or 68 k
(1070 mA setting) (Note 4)
ILIM4
—
1280
—
mA
ILIM Resistor = 15 k or 82 k
(1280 mA setting) (Note 4)
ILIM5
—
1600
—
mA
ILIM Resistor = 18 k or 100 k
(1600 mA setting) (Note 4)
ILIM6
—
2130
—
mA
ILIM Resistor = 22 k or 120 k
(2130 mA setting) (Note 4)
ILIM7
—
2670
—
mA
ILIM Resistor = 27 k or 150 k
(2670 mA setting) (Note 4)
ILIM8
3000
3200
3400
mA
ILIM Resistor = 33 k or VDD
(3200 mA setting)
tPIN_WAKE
—
3
—
ms
SMBus Wake Time
tSMB_WAKE
—
4
—
ms
Idle Sleep Time
tIDLE_SLEEP
—
200
—
ms
TREG
—
110
—
°C
Die Temperature at which
current limit will be reduced
TREG_HYST
—
10
—
°C
Hysteresis for tREG functionality.
Temperature must drop by this
value before ILIM value restored
to normal operation
Back-drive Current
Selectable Current Limits
Pin Wake Time
Thermal Regulation Limit
Thermal Regulation
Hysteresis
Note 1:
2:
3:
4:
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
 2015 Microchip Technology Inc.
DS20005424B-page 5
UCS2112
TABLE 1-2:
ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Symbol
Min.
Typ.
Max.
Unit
Thermal Shutdown
Threshold
TTSD
—
135
—
°C
Die Temperature at which port
power switch will turn off
Thermal Shutdown
Hysteresis
TTSD_HYST
—
35
—
°C
After shutdown due to TTSD
being reached, die temperature
drop required before port power
switch can be turned on again
Auto-recovery Test Current
ITEST
—
190
—
mA
Portable device attached,
VBUS= 0 V, Die temp < TTSD
Auto-recovery Test Voltage
VTEST
—
750
—
mV
Portable device attached,
VBUS = 0 V before application,
Die temp < TTSD
Programmable, 250 - 1000 mV,
default listed
RDISCHARGE
—
100
—

Discharge Impedance
Conditions
Port Power Switch - AC Parameters
Turn-On Delay
tON_PSW
—
200
—
ms
Depends on the VBUS Discharge
setting.
Programmable 100-400 ms,
default listed
Turn-Off Time
tOFF_PSW_INA
—
0.75
—
ms
PWR_EN inactive toggle to
switch off time
CBUS = 120 µF
Turn-Off Time
tOFF_PSW_ERR
—
1
—
ms
Over-current Error, VBUS Min
Error, or Discharge Error to
switch off
CBUS = 120 µF
Turn-Off Time
tOFF_PSW_ERR1
—
100
—
ns
TSD or Back-drive Error to
switch off
CBUS = 120 µF
tR_BUS
—
1.1
—
ms
Measured from 10% to 90% of
VBUS, CLOAD = 220 µF
ILIM = 1.0A
Soft Turn-On Rate
IBUS/t
—
100
—
mA/µs
Temperature Update Time
tDC_TEMP
—
200
—
ms
Short-Circuit Response Time
tSHORT_LIM
—
1.5
—
µs
Time from detection of short to
current limit applied.
No CBUS applied
Short-Circuit Detection Time
tSHORT
—
6
—
ms
Time from detection of short to
port power switch disconnect
and ALERT# pin assertion.
tUL
—
7
—
ms
From PWR_EN edge transition
from inactive to active to begin
error recovery
VBUS Output Rise Time
Latched Mode Cycle Time
Note 1:
2:
3:
4:
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
DS20005424B-page 6
 2015 Microchip Technology Inc.
UCS2112
TABLE 1-2:
ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Auto-recovery Mode Cycle
Time
Auto-recovery Delay
Discharge Time
Symbol
Min.
Typ.
Max.
Unit
Conditions
tCYCLE
—
25
—
ms
Time delay before error
condition check
Programmable 15-50 ms,
default listed
tTST
—
20
—
ms
Portable device attached, VBUS
must be > VTEST after this time
Programmable 10-25 ms,
default listed
tDISCHARGE
—
200
—
ms
Amount of time discharge
resistor applied
Programmable 100-400 ms,
default listed
Port Power Switch Operation With Trip Mode Current Limiting
Region 2 Current
Keep-out
IBUS_R2MIN_1
—
—
0.1
A
Note 2
Minimum VBUS
Allowed at Output
VBUS_MIN_1
2.0
—
—
V
Note 2
Port Power Switch Operation With Constant Current Limiting (Variable Slope)
Region 2 Current
Keep-out
IBUS_R2MIN
—
—
2.13
A
Note 2
Minimum VBUS
Allowed at Output
VBUS_MIN
2.0
—
—
V
Note 2
Current Measurement - DC
Current Measurement Range
Reported Current
Measurement Resolution
IBUS_M
0
—
3400
mA
Range (Note 2 and Note 3)
IBUS_M
—
13.3
—
mA
1 LSB
—
±2
—
%
—
±2
—
LSB
Current Measurement
Accuracy
200 mA < IBUS < ILIM
IBUS < 200 mA
Current Measurement - AC
Sampling Rate
Conversion Time
both channels
—
—
1.1
—
ms
Note 2
tCONV
—
2.2
—
ms
All registers updated in digital
(Note 2)
Charge Rationing - DC
Accumulated Current
Measurement Accuracy
—
—
±4.5
—
%
Charge Rationing - AC
Current Measurement
Update Time
Note 1:
2:
3:
4:
tPCYCLE
—
1
—
s
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
 2015 Microchip Technology Inc.
DS20005424B-page 7
UCS2112
TABLE 1-2:
ELECTRICAL SPECIFICATIONS (CONTINUED)
Electrical Characteristics: Unless otherwise specified, VDD = 4.5V to 5.5V, VS = 2.9V to 5.5V,
VPULLUP = 3V to 5.5V, TA = -40°C to 105°C. All typical values at VDD = VS = 5V, TA = 27°C.
Characteristic
Symbol
Min.
Typ.
Max.
Unit
Conditions
Attach / Removal Detection
VBUS Bypass - DC
On Resistance
RON_BYP
—
45
—
Ω
Leakage Current
ILEAK_BYP
—
—
3
µA
Switch off TA < +85°C (Note 1)
Current Limit
IDET_CHG/
IBUS_BYP
—
700
—
µA
VDD = 5V and VBUS> 4.75V
tDET_CHARGE
—
800
—
ms
CBUS = 500 µF maximum
VBUS Charge Time for
Attachment
Attach/Removal Detection - DC
Attach Detection
Threshold
Primary Removal
Detection Threshold
IDET_QUAL
—
800
—
µA
Programmable 200-1000 µA,
default listed
IREM_QUAL_ACT
—
700
—
µA
Programmable 100-900 µA,
default listed. Active power state
IREM_QUAL_DET
—
800
—
µA
Programmable, default listed.
Detect power state
Time from Attach to A_DET#
assert.
Attach/Removal Detection - AC
Attach Detection Time
tDET_QUAL
—
100
—
ms
Removal Detection Time
tREM_QUAL
—
1000
—
ms
Note 1:
2:
3:
4:
This parameter is characterized, not 100% tested.
This parameter is ensured by design and not 100% tested.
The current measurement full scale range maximum value is 3.4A. However, the UCS2112 cannot report values above
ILIM (if IBUS_R2MIN  ILIM) or above IBUS_R2MIN (if IBUS_R2MIN > ILIM and ILIM  1.6A).
This parameter is characterized, not 100% production tested.
T LOW
T HD:STA
T HIGH
T SU:STO
T FALL
SMCLK
T RISE
T HD:STA
T SU:DAT
T HD:DAT
T SU:STA
SMDATA
TBUF
S
P
FIGURE 1-1:
TABLE 1-3:
S
S - Start Condition
P - Stop Condition
P
SMSBus Timing.
TEMPERATURE SPECIFICATIONS
Parameters
Sym.
Min.
Typ.
Max.
Units
Operating Temperature Range
TA
-40
—
+105
°C
Storage Temperature Range
TA
-55
—
+150
°C
Conditions
Temperature Ranges
Thermal Package Resistances - see Table 1-1
DS20005424B-page 8
 2015 Microchip Technology Inc.
UCS2112
1.1
ESD and Transient Performance
TABLE 1-4:
ESD RATINGS
ESD Specification
Rating or Value
Human Body Model (JEDEC JESD22-A114) - All pins
8 kV
Charged Device Model (JEDEC JESD22-C101) - All pins
500V
1.1.1
HUMAN BODY MODEL (HBM)
PERFORMANCE
HBM testing verifies the ability to withstand ESD strikes
like those that occur during handling and manufacturing and is done without power applied to the IC. To pass
the test, the device must have no change in operation
or performance due to the event.
1.1.2
CHARGED DEVICE MODEL (CDM)
PERFORMANCE
CDM testing verifies the ability to withstand ESD strikes
like those that occur during handling and assembly with
pick and place style machinery and is done without
power applied to the IC. To pass the test, the device
must have no change in operation or performance due
to the event.
 2015 Microchip Technology Inc.
DS20005424B-page 9
UCS2112
NOTES:
DS20005424B-page 10
 2015 Microchip Technology Inc.
UCS2112
2.0
TYPICAL PERFORMANCE CURVES
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
Note: Unless otherwise indicated, VDD = VS = 5V, TA = +27°C.
6
VS = VDD = 5V
ILIM = 3A min (3.4A max), short applied at 2 ms
5
6
6
5
5
4
4
VBUS
3
2
2
1
1
VBUS
0
5
Time (ms)
-1
FIGURE 2-4:
Short Applied After
VDD
ALERT#
4
6
45
5
40
4
3
3
2
2
1
1
IBUS
0
0
-1
-1
0
100
200
300
400
6
300
400
500
VBUS Discharge Behavior.
35
30
25
20
15
10
5
-40
-15
10
35
60
85
110
Temperature (°C)
Power-Up Into a Short.
VS = VDD = 5V
ILIM = 2.13A (typical), short applied at 10 µs
5
200
0
500
Time (ms)
FIGURE 2-2:
100
Time (ms)
6
5
0
10
On Resistance (mΩ)
FIGURE 2-1:
Power-Up.
2
0
-1
0
3
1
0
-1
Voltage (V)
Voltage (V)
3
Current (A)
Voltage (V)
IBUS
Current (A)
ALERT#
4
FIGURE 2-5:
Power Switch On
Resistance vs. Temperature.
28
24
4
20
3
16
2
12
1
8
Current (A)
Voltage (V)
VBUS
4
0
IBUS
-1
0
-4
-2
0
20
40
Time (µs)
FIGURE 2-3:
Response.
Internal Power Switch Short
 2015 Microchip Technology Inc.
DS20005424B-page 11
UCS2112
6.10
6.08
6.06
6.04
6.02
6.00
5.98
5.96
5.94
5.92
5.90
0%
Current Limit Accuracy %)
VS Threshold Voltage (V)
Note: Unless otherwise indicated, VDD = VS = 5V, TA = +27°C.
VDD = 5V
-40
-15
10
35
60
85
VS = VDD = 5V
ILIM = 3.0A min. (3.2A typ., 3.4A max.)
-2%
Note: The percentage is relative to the
maximum specification (3.4A)
-4%
-6%
-8%
-10%
-12%
110
-40
-15
Temperature (°C)
3.0
2.9
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
2.0
VS Overvoltage Threshold
FIGURE 2-9:
vs. Temperature.
60
85
110
Trip Current Limit Operation
4
3
Threshold
Hysteresis
2
1
0
-1
-2
-3
-4
-40
-15
10
35
60
85
-5
110
0.0
0.5
1.0
Temperature (°C)
FIGURE 2-7:
vs. Temperature.
VS Undervoltage Threshold
FIGURE 2-10:
Accuracy.
Supply Current (ȝA)
5.0
VBUS1
4.0
VBUS2
3.0
2.0
VS = VDD = 5V;
ATT_DET enabled;
PWR_EN disabled for one chanel
and enabled for the other channel.
1.0
0.0
0
500
1000
1500
2000
2500
Current (µA)
FIGURE 2-8:
DS20005424B-page 12
1.5
2.0
2.5
3.0
Current (A)
6.0
Voltage (V)
35
5
VDD = 5V
Accuracy (%)
VS Threshold Voltage (V)
FIGURE 2-6:
vs. Temperature.
10
Temperature (°C)
Detect State VBUS vs. IBUS.
1000
900
800
700
600
500
400
300
200
100
0
IBUS Measurement
IDD + IS1 + IS2
IDD
IS1 + IS2
-40
-15
10
35
60
85
110
Temperature (°C)
FIGURE 2-11:
Active State Current vs.
Temperature (both channels on,
PWR_EN1 = PWR_EN2 = 1).
 2015 Microchip Technology Inc.
UCS2112
Note: Unless otherwise indicated, VDD = VS = 5V, TA = +27°C.
700
60%
IDD + IS1 + IS2
50%
500
IDD
Samples (%)
400
300
IS1 + IS2
200
100
40%
30%
20%
10%
FIGURE 2-12:
Active State Current vs.
Temperature (only one channel on,
PWR_EN1 = 1, PWR_EN2 = 0).
FIGURE 2-15:
Distribution.
300
ILIM1 Trip Current
60%
250
50%
IDD + IS1 + IS2
40%
200
Samples (%)
IDD
150
100
50
IS1 + IS2
Detect State Current vs.
FIGURE 2-16:
Distribution(1).
14
60%
12
50%
Samples (%)
10
IDD + IS1 + IS2
8
6
1.01
1
0.99
0.98
VBUS Current (A)
Temperature (°C)
FIGURE 2-13:
Temperature.
0.97
110
0.96
85
0.95
60
0.94
35
0.93
10
10%
0.91
-15
20%
0%
0
-40
30%
0.92
IDD
4
ILIM2 Trip Current
40%
30%
20%
10%
IS1 + IS2
Sleep State Current vs.
1.12
VBUS Current (A)
Temperature (°C)
FIGURE 2-14:
Temperature.
1.11
110
1.1
85
1.09
60
1.08
35
1.07
10
1.06
-15
1.04
-40
1.03
0%
0
1.02
2
1.05
Supply Current (ȝA)
0.555
VBUS Current (A)
Temperature (°C)
Supply Current (ȝA)
0.55
110
0.54
85
0.545
60
0.535
35
0.53
10
0.525
-15
0.52
-40
0.515
0
0.51
0%
0.505
Supply Current (ȝA)
600
FIGURE 2-17:
Distribution(1).
ILIM3 Trip Current
Note 1: The histogram aspect is caused by a mixture of two normal distributions, corresponding to the two
VBUS channels.
 2015 Microchip Technology Inc.
DS20005424B-page 13
UCS2112
60%
50%
50%
40%
40%
40%
40%
2.745
2.72
3.32
3.28
3.24
3.2
3.16
3
1.675
1.66
1.645
1.63
0%
1.615
0%
1.6
10%
1.585
10%
3.12
20%
3.08
20%
ILIM7 Trip Current
30%
3.04
30%
1.57
2.795
50%
1.555
3.4
50%
Samples (%)
60%
1.54
2.77
FIGURE 2-21:
Distribution.
ILIM4 Trip Current
VBUS Current (A)
VBUS Current (A)
FIGURE 2-19:
Distribution(1).
2.695
VBUS Current (A)
60%
1.525
Samples (%)
FIGURE 2-18:
Distribution(1).
3.36
VBUS Current (A)
2.67
2.545
1.33
1.32
1.31
1.3
1.29
1.28
1.27
0%
1.26
0%
1.25
10%
1.24
10%
2.645
20%
2.62
20%
30%
2.595
30%
2.57
Samples (%)
60%
1.23
Samples (%)
Note: Unless otherwise indicated, VDD = VS = 5V, TA = +27°C.
FIGURE 2-22:
Distribution.
ILIM5 Trip Current
ILIM8 Trip Current
60%
Samples (%)
50%
40%
30%
20%
10%
2.23
2.21
2.19
2.17
2.15
2.13
2.11
2.09
2.07
2.05
2.03
0%
VBUS Current (A)
FIGURE 2-20:
Distribution.
ILIM6 Trip Current
Note 1: The histogram aspect is caused by a mixture of two normal distributions, corresponding to the two
VBUS channels.
DS20005424B-page 14
 2015 Microchip Technology Inc.
PIN DESCRIPTION
Descriptions of the pins are listed in Table 3-1.
TABLE 3-1:
PIN FUNCTION TABLE
UCS2112
4x4 QFN
Symbol
1
PWR_EN1
2
Function
Pin Type
Connection Type if Pin Not Used
Port power switch enable #1
DI
Connect to ground or VDD
(depending on the polarity decoded via
COMM_ILIM pin)
A_DET#1
Open-drain output for Attach Detection on VBUS1 (requires pullup resistor)
OD
Connect to ground
3
BOOST#
Logic output for DC-DC converter voltage increase (requires
pull-up resistor)
OD
Connect to ground
4, 5
VBUS1
Port power switch #1 output (requires both pins tied together)
High Power, AIO
Leave open
6, 7
VS
Voltage input to port power switch VBUS1 (requires both pins
tied together)
High Power, AIO
Connect to ground
 2015 Microchip Technology Inc.
8
VDD
9, 10
VS
Voltage input to port power switch VBUS2 (requires both pins
tied together)
High Power, AIO
Connect to ground
11, 12
VBUS2
Port power switch #2 output (requires both pins tied together)
High Power, AIO
Leave open
13
COMM_ILIM
Enables SMBus or Stand-Alone mode at power-up. Hardware
strap for maximum current limit
AIO
N/A
14
A_DET#2
Open-drain output for Attach Detection on VBUS2
(requires Pull Up)
OD
Connect to ground
15
PWR_EN2
Port power switch enable #2
DI
Connect to ground or VDD
(depending on the polarity decoded via
COMM_ILIM pin)
16
ALERT#2
Output fault ALERT for VBUS2 (requires pull-up resistor)
OD
Connect to ground
17
SMCLK
SMCLK - SMBus clock input (requires pull-up resistor)
DI
Connect to VPULLUP(or to ground in
Stand-alone mode)
18
SMDATA
SMDATA - SMBus data input/output (requires pull-up resistor)
DIOD
Connect to VPULLUP (or to ground in
Stand-alone mode)
19
GND
Ground
Power
N/A
20
ALERT#1
21
EP
Common supply voltage
Power
N/A
Output fault ALERT for VBUS1 (requires pull-up resistor)
OD
Connect to ground
Exposed thermal pad. Must be connected to electrical ground.
EP
N/A
UCS2112
DS20005424B-page 15
3.0
UCS2112
TABLE 3-2:
PIN TYPES
Pin Type
Power
Description
This pin is used to supply power or
ground to the device.
Hi-Power This pin is a high-current pin.
AIO
Analog Input/Output - this pin is used as
an I/O for analog signals.
DI
Digital Input - this pin is used as a digital
input.
DIOD
Open-Drain Digital Input/Output - this
pin is bidirectional. It is open-drain and
requires a pull-up resistor.
OD
Open-Drain Digital Output - used as a
digital output. It is open-drain and
requires a pull-up resistor.
EP
Exposed thermal pad
DS20005424B-page 16
 2015 Microchip Technology Inc.
UCS2112
4.0
TERMS AND ABBREVIATIONS
Note:
The PWR_EN1 and PWR_EN2 pins each have configuration bits (“<pin name>_S” in General
Configuration 1 register (Address 11h) and General Configuration 2 register (Address 12h)) that may be
used to perform the same function as the external pin state. These bits are accessed via the SMBus/I2C™
and are OR’d with the respective pin. This OR’d combination of pin state and register bit is referenced as
the <pin name> control.
TABLE 4-1:
TERMS AND ABBREVIATIONS
Term/Abbreviation
Attach Detection
Description
An Attach Detection event occurs when the current drawn by a portable device is greater than
IDET_QUAL for longer than tDET_QUAL.
Attachment
The physical insertion of a portable device into a USB port that UCS2112 is controlling.
CC
Constant Current
CDM
Charged Device Model. JEDEC model for characterizing susceptibility of a device to damage
from ESD.
Current Limiting
Mode
Determines the action that is performed when the IBUS current reaches the ILIM threshold. Trip
opens the port power switch. Constant Current (variable slope) allows VBUS to be dropped by
the portable device.
Disconnection
USB-IF term which refers to the loss of active USB communications between a USB host and
a USB device.
Dynamic Thermal
Management
The UCS2112 automatically adjusts port power switch limits and modes to lower internal
power dissipation when the thermal regulation temperature value is approached.
HBM
Human Body Model
IBUS_R2MIN
Current limiter mode boundary
ILIM
The IBUS current threshold used in current limiting. In Trip mode, when ILIM is reached, the
port power switch is opened. In Constant Current mode, when the current exceeds ILIM, operation continues at a reduced voltage and increased current; if VBUS voltage drops below
VBUS_MIN, the port power switch is opened.
OCL
Overcurrent limit
POR
Power-on Reset
Portable Device
USB device attached to the USB port.
Removal Detection
A Removal Detection event occurs when the current load on the VBUS pin drops to less than
IREM_QUAL for longer than tREM_QUAL.
Removal
The physical removal of a portable device from a USB port that the UCS2112 is controlling.
Stand-Alone Mode
Indicates that the communications protocol is not active and all communications between the
UCS2112 and a controller are done via the external pins only (PWR_EN1 and PWR_EN2 as
inputs, and ALERT1#, ALERT2#, A_DET1# and A_DET2# as outputs).
 2015 Microchip Technology Inc.
DS20005424B-page 17
UCS2112
NOTES:
DS20005424B-page 18
 2015 Microchip Technology Inc.
UCS2112
5.0
GENERAL DESCRIPTION
The UCS2112 is a dual-port power switch. Two USB
power ports are supported with current limits up to 3.0A
continuous current (3.4A maximum) each. Selectable
and programmable current limiting configurations are
also available to the application. A typical block diagram is shown in Figure 5-1.
D+
DVBUS
VB
SMDATT
SMCLK
USB Port 1
Connector
S
SMDAT
SSMCLK
D+
DPD_ALERT1
2 PORT HUB
VBUS1
ALERT1
A_DET1
PWR_EN1
UCS2112
VBUS2
ALERT2
A_DET2
PWR_EN2
D+
DPD_ALERT2
FIGURE 5-1:
VBUS
V
D+
D-
USB Port 2
Connector
Typical USB Application.
 2015 Microchip Technology Inc.
DS20005424B-page 19
UCS2112
5.1
UCS2112 Power States
Power states are indicators of the device’s current
consumption in the System and the functionality of the
Digital Logic. Table 5-1 details the UCS2112 power
states.
TABLE 5-1:
POWER STATES DESCRIPTION
State
Description
Off
This power state is entered when the voltage at the VDD pin voltage is < VDD_TH. In this state, the device is considered “off”. The UCS2112 will not retain its digital states and register contents nor respond to SMBus/I2C™
communications. The port power switch and bypass switch will be off. See Section 5.1.1 “Off State Operation”.
Sleep
This is the lowest power state available. While in this state, the UCS2112 will retain digital functionality and wake
to respond to SMBus/I2C communications. See Section 5.1.2 “Sleep State Operation”.
Detect
The Detect power state should not be confused with the actual Attach / Removal Detection feature. Detect Power
State is both channels awaiting attachment. This is a lower-current power state. In this state, the device is actively
looking for a portable device to be attached. While in this state, the UCS2112 will retain the configuration and
charge rationing data, but it will not monitor the bus current. SMBus/I2C communications will be fully functional.
See Section 5.1.3 “Detect State Operation”.
Error
This power state is entered when a fault condition exists. Error power state is one or both channels in Fault Handling. This state is updated as Priority One. The Interrupt Status Registers for each channel will update the fault
detected per channel. Only the channel that has detected a Fault will be affected since the other channel can
remain active if no fault is detected. See Section 5.1.5 “Error State Operation”.
Active
Active power State is one, or both channels active and sourcing current to the VBUS Port. This state is updated
as Priority Two. None of the channels have detected Fault. This power state provides full functionality. While in
this state, operations include activation of the port power switch, current limiting, and charge rationing. See
Section 5.1.4 “Active State Operation”.
Table 5-2 shows the settings for the various power
states, except Off and Error. If VDD < VDD_TH, the
UCS2112 is in the Off state.
TABLE 5-2:
POWER STATES CONTROL SETTINGS
Power
PWR_EN1 PWR_EN2 ATT_DET
State
Portable
Device
Attached
Behavior
Sleep
disabled
disabled
N/A
N/A
• All switches disabled.
• VBUS will be near ground potential.
• The UCS2112 wakes to respond to SMBus
communications.
Detect
enabled
disabled
enabled
No
• Automatic transition to Active state when conditions
met for VBUS1(see Section 5.1.3.1 “Automatic
Transition from Detect to Active”).
• VBUS2 pins have very low current delivery capability.
disabled
enabled
enabled
No
• Automatic transition to Active state when conditions
met for VBUS2 (see Section 5.1.3.1 “Automatic
Transition from Detect to Active”).
• VBUS1 pins have very low current delivery capability.
enabled
enabled
enabled
No
• Automatic transition to Active state when conditions
met for both VBUS1 and VBUS2 (see Section 5.1.3.1
“Automatic Transition from Detect to Active”).
DS20005424B-page 20
 2015 Microchip Technology Inc.
UCS2112
TABLE 5-2:
POWER STATES CONTROL SETTINGS (CONTINUED)
Power
PWR_EN1 PWR_EN2 ATT_DET
State
Active
5.1.1
Portable
Device
Attached
enabled
disabled
N/A
Yes
• Port power switch is on during A_DET1=1 for VBUS1.
VBUS2 pins have very low current delivery capability.
disabled
enabled
N/A
Yes
• Port power switch is on during A_DET2=1 for VBUS2.
• VBUS1 pins have very low current delivery capability.
enabled
enabled
N/A
Yes
• Port power switch is on during A_DET1=A_DET2=1
for VBUS1 and VBUS2.
enabled
disabled
disabled
N/A
• Forced ACTIVE Power State: Port power switch is on
at all times for VBUS1.
• VBUS2 pins have very low current delivery capability.
disabled
enabled
disabled
N/A
• Forced ACTIVE Power State: Port power switch is on
at all times for VBUS2.
• VBUS1 pins have very low current delivery capability.
enabled
enabled
disabled
N/A
• Forced ACTIVE Power State: Port power switch is on
at all times for VBUS1 and VBUS2.
OFF STATE OPERATION
The device will be in the Off state if VDD is less than
VDD_TH. When the UCS2112 is in the Off state, it will do
nothing and all circuitry will be disabled. Digital register
values are not stored and the device will not respond to
SMBus commands.
5.1.2
Behavior
SLEEP STATE OPERATION
The PWR_EN1 and PWR_EN2 pins may be used to
cause the UCS2112 to enter/exit Sleep. These pins are
AND’ed for Sleep mode.
The first data byte read from the UCS2112 when it is in
the Sleep state will wake it; however, the data to be
read will return all 0’s and should be considered invalid.
This is a “dummy” read byte meant to wake the
UCS2112. Subsequent read or write bytes will be
accepted normally. After the dummy read, the
UCS2112 will be in a higher-power state (see
Figure 5-2). After communication has not occurred for
tIDLE_SLEEP, the UCS2112 will return to Sleep.
When the UCS2112 is in the Sleep state, the device will
be in its lowest-power state. The bypass switch and the
port power switch will be disabled. The Attach and
Removal Detection feature will be disabled. VBUS1 and
VBUS2 will be near ground potential. The ALERT#1
and ALERT#2 pins will not be asserted. If asserted
prior to entering the Sleep state, the ALERT# pin will be
released. SMBus activity is limited to single byte read
or write.
SMBus Read
Dummy read returns invalid data
and places device in temporary
Read returns valid data
Active state
S 0101_1110 A 0001_0000 A S 0101_1111 A invalid dataN P
Power State
FIGURE 5-2:
S 0101_1110 A 0001_0000 A S 0101_1111 A valid data N P
tSMB_WAKE
temporary Active state
(not all functionality available)
Sleep
tIDLE_SLEEP
Sleep
Wake from Sleep using SMBus Read.
 2015 Microchip Technology Inc.
DS20005424B-page 21
UCS2112
5.1.3
DETECT STATE OPERATION
When the UCS2112 is in the Detect state, the port power
switch will be disabled. The VBUS output will be connected to the VDD voltage by a secondary bypass switch.
There are two methods for transitioning from the Detect
state to the Active state: automatic and host-controlled.
5.1.3.1
Automatic Transition
from Detect to Active
For the Detect state, enable PWR_EN1 and/or
PWR_EN2, and supply VDD ≥ VDD_TH. When a portable device is attached and an Attach Detection event
occurs, the UCS2112 will automatically transition to the
Active state.
5.1.3.2
State Change from Detect to Active
When conditions cause the UCS2112 to transition from
the Detect state to the Active state, the following
occurs:
• The Attach Detection feature will be disabled; the
Removal Detection feature remains enabled.
• The bypass switch will be turned off.
• The discharge switch will be turned on briefly for
tDISCHARGE.
• The port power switch will be turned on.
5.1.4
ACTIVE STATE OPERATION
Every time the UCS2112 enters the Active state, the
port power switches are closed. The UCS2112 cannot
be in the Active state (and therefore, the port power
switch cannot be turned on) if any of the following conditions exist:
• An overcurrent condition has been detected.
• An undervoltage condition on either VBUS pin has
been detected (see Section 5.3.4 “Undervoltage
Lockout on VS”).
• A back-drive condition has been detected (see
Section 5.3.2 “Back-voltage Detection”).
• A discharge error has been detected.
• An overvoltage condition on the VS pin.
The UCS2112 will enter the Error state from the Detect
state when a back-drive condition has been detected
on either port, or when the maximum allowable internal
die temperature has been exceeded.
The UCS2112 will enter the Error state from the Sleep
state when a back-drive condition has been detected.
When the UCS2112 enters the Error state, the port
power switch and the VBUS bypass switch will be disabled while the ALERT# pin is asserted (by default).
They will remain off while in this power state. The
UCS2112 will leave this state as determined by the fault
handling selection.
With the Auto-recovery fault handler, after the tCYCLE
time period, the UCS2112 will check that all of the error
conditions have been removed.
If all of the error conditions have been removed, the
UCS2112 will return to the Active state or Detect state,
as applicable.
If the device is in the Error state and a Removal Detection event occurs, it will check the error conditions and
then return to the power state defined.
5.2
Communication
The UCS2112 will enter the Error state from the Active
state when any of the following events are detected:
The UCS2112 can operate in SMBus mode (see
Section 8.0 “System Management Bus Protocol”)
or Stand-alone mode. The resistor connected to the
COMM_ILIM pin determines the operating mode and
the hardware-set ILIM setting, as shown in Table 5-3.
Unless connected to GND or VDD, the resistors in
Table 5-3 are external pull-down resistors.
• The maximum allowable internal die temperature
(TTSD) has been exceeded.
The SMBus address is specified in Section 8.2
“SMBus Address and RD/WR Bit”.
• VS < VS_UVLO
• PWR_EN1 and PWR_EN2 are disabled.
5.1.5
ERROR STATE OPERATION
TABLE 5-3:
COMMUNICATION DECODE
COMM_ILIM Pulldown
Resistor (±1%)
PWR_EN1 and
PWR_EN2 Polarity
ILIM (A)
Total ILIM (A)
(Note 1)
Communication
Mode
GND
Active-High
0.53
0.53+0.53
SMBUS
10 k
Active-High
0.96
0.96+0.96
SMBUS
12 k
Active-High
1.07
1.07+1.07
SMBUS
15 k
Active-High
1.28
1.28+1.28
SMBUS
18 k
Active-High
1.6
1.6+1.6
SMBUS
22 k
Active-High
2.13
2.13+2.13
SMBUS
DS20005424B-page 22
 2015 Microchip Technology Inc.
UCS2112
TABLE 5-3:
COMMUNICATION DECODE (CONTINUED)
COMM_ILIM Pulldown
Resistor (±1%)
PWR_EN1 and
PWR_EN2 Polarity
ILIM (A)
Total ILIM (A)
(Note 1)
Communication
Mode
27 k
Active-High
2.67
2.67+2.67
SMBUS
33 k
Active-High
3.2
3.2+3.2
SMBUS
47 k
Active-Low
0.53
0.53+0.53
Stand-Alone
56 k
Active-Low
0.96
0.96+0.96
Stand-Alone
68 k
Active-Low
1.07
1.07+1.07
Stand-Alone
82 k
Active-Low
1.28
1.28+1.28
Stand-Alone
100 k
Active-Low
1.6
1.6+1.6
Stand-Alone
120 k
Active-Low
2.13
2.13+2.13
Stand-Alone
150 k
Active-Low
2.67
2.67+2.67
Stand-Alone
VDD
Active-Low
3.2
3.2+3.2
Stand-Alone
Note 1:
5.3
5.3.1
The total maximum current depends on power dissipation characteristics of the design (see Table 1-1)
Supply Voltages
VDD SUPPLY VOLTAGE
The UCS2112 requires 4.5V to 5.5V present on the
VDD pin for core device functionality. Core device functionality consists of maintaining register states,
wake-up upon SMBus/I2C query and Attach Detection.
5.3.2
BACK-VOLTAGE DETECTION
The back drive detector is functional in all power states
(Sleep, Detect, and Active).
When in Sleep, the UCS2112 will enter the Error state
from Sleep if a Back Drive condition was detected.
Whenever the following condition is true for either port,
the port power switch will be disabled, the VBUS bypass
switch will be disabled and a back-voltage event will be
flagged. This will cause the UCS2112 to enter the Error
power state (see Section 5.1.5 “Error State Operation”).
Note:
The VBUS voltage exceeds the VS and/or
the VDD pin voltage by VBV_TH and the
port power switch is closed. The port
power switch will be opened immediately.
If the condition lasts for longer than tMASK,
then the UCS2112 will enter the Error
state. Otherwise, the port power switch
will be turned on as soon as the condition
is removed.
 2015 Microchip Technology Inc.
5.3.3
BACK-DRIVE CURRENT
PROTECTION
If a portable device is attached that is self-powered, it
may drive the VBUS port to its power supply voltage
level; however, the UCS2112 is designed such that
leakage current from the VBUS pins to the VDD and/or
the VS pin shall not exceed IBD_1 (if the VDD and/or VS
voltage is zero) or IBD_2 (if the VDD and/or VS voltage
exceeds VDD_TH).
5.3.4
UNDERVOLTAGE LOCKOUT ON VS
The UCS2112 requires a minimum voltage (VS_UVLO)
be present on the VS pin for Active power state.
5.3.5
OVERVOLTAGE DETECTION AND
LOCKOUT ON VS/VDD
The UCS2112 port power switch will be disabled if the
voltage on the VS pin exceeds a voltage (VS_OV) for
longer than the specified time (tMASK). This will cause
the device to enter the Error state.
5.3.6
PWR_EN1 AND PWR_EN2 INPUT
The PWR_EN control affects the power state and
enables the port power switch to be turned on if conditions are met (see Table 5-2). The port power switch
cannot be closed if PWR_EN is disabled. However, if
PWR_EN is enabled, the port power switch is not necessarily closed (see Section 5.1.4 “Active State
Operation”). In SMBus mode, the PWR_EN1 and
PWR_EN2 pins states will be ignored by the UCS2112
if the PIN_IGN configuration bit is set; otherwise, the
PWR_EN1S and PWR_EN2S configuration bits are
checked along with the pins.
DS20005424B-page 23
UCS2112
BOOST# OUTPUT PIN
If R 1  R 3
SMDATA/LOW_ILM
SMCLK/LOAD_SHARE
ALERT#2
18
17
16
 R 1 + R 2 + R 3   V FB
5V OUT = -------------------------------------------------------R3
 R2 + R 3   R 1  V FB
V
= -------------------------------------------------------OUT
R3  R4
 5V OUT R 1  R 1  V FB
V OUT =  -------------------- – ------   -----------------------R4
R3 
 V FB
GND
The UCS2112 has two independent ALERT# out pins.
ALERT#1 is tied to the status of the VBUS1 pin.
ALERT#2 is tied to the status of the VBUS2 pin.
The ALERT# pin is an active-low open-drain interrupt
to the host controller. The ALERT# pin is asserted
when an error occurs. The ALERT# pin can also be
asserted when the LOW_CUR (portable device is pulling less current and may be finished charging) or
TREG (thermal regulation temperature exceeded) bits
are set and linked. As well, when charge rationing is
enabled, the ALERT# pin is asserted by default when
the current rationing threshold is reached (as determined by RATION_BEH<1:0>). The ALERT# pin is
released when all error conditions that may assert the
ALERT# pin (such as an error condition, charge
rationing, and TREG and LOW_CUR if linked) have
been removed or reset as necessary.
19
The UCS2112 provides a BOOST# output pin to compensate for voltage drops during high loads. The
BOOST# pin is an active-low, open-drain output that
would be connected to a resistor in the DC-DC Converter’s feedback error voltage loop (see Figure 5-3).
The
BOOST#
pin
is
asserted
when
VBUS Current > IBOOST. IBOOST typical value is 1.9A.
The BOOST# is OR’ed for both VBUS1 and VBUS2 ports.
When the BOOST# pin is asserted, it will remain in this
state for at least tBOOST_MAT (minimum assertion time).
ALERT#1 AND ALERT#2 OUTPUT
PINS
ALERT#1
5.4.1
5.4.2
Discrete Output Pins
20
5.4
5V OUT  R 1
VOUT  --------------------------------R
4
5.0VOUT
PWR_EN1
1
15
PWR_EN2
A_DET#1
2
14
A_DET#2
13
COMM_ILIM
R1
R4
DC-DC
Converter Block
R2
VFB
FeedBack
BOOST#
UCS2112
20-QFN 4x4 mm
3
VBUS1
4
12
VBUS2
VBUS1
5
11
VBUS2
5.5
5.5.1
9
8
7
10
VS
VS
GND FLAG
Boost# Pin Usage.
Discrete Input Pins
COMM_ILIM INPUT
The COMM_ILIM input determines the communications mode, as shown in Table 7-1. This is also the
hardware strap for MAX Current Limit.
5.5.2
VDD
VS
FIGURE 5-3:
VS
6
R3
GND
5.5.3
SMDATA
When used in Stand-Alone, this pin should be tied to
ground.
When the UCS2112 is configured for SMBus communications, the SMDATA is the data input/output.
SMCLK
When operated in Stand-Alone mode, this pin should be
tied to ground. When the UCS2112 is configured for
SMBus communications, the SMCLK is the clock input.
DS20005424B-page 24
 2015 Microchip Technology Inc.
UCS2112
6.1.3
6.0
DETECT STATE
6.1
Device Attach / Removal Detection
The UCS2112 can detect the attachment and removal
of a portable device on the VBUS1 or VBUS2 ports.
Note:
6.1.1
By default, device attach / removal detection feature is disabled. It can be enabled
by clearing ATT_DISABLE bit 6 from
Register 9-9
VBUS BYPASS SWITCH
The UCS2112 contains circuitry to provide VBUS current as shown in Figure 6-1. In the Detect state, VDD is
the voltage source; in the Active state, VS is the voltage
source. The bypass switch and the port power switch
are never both on at the same time.
REMOVAL DETECTION
The Removal Detection feature will be active in the
Active and Detect power states. This feature monitors
the current load on the VBUS1 and VBUS2 pins. If this
load drops to less than IREM_QUAL_DET for longer than
tREM_QUAL, a Removal Detection event is flagged.
When a Removal Detection event is flagged, the following will be done:
1.
2.
3.
4.
Disable the port power switch and the bypass
switch.
Set the REM status register bit.
Enable an internal discharging device that will
discharge the VBUS line within tDISCHARGE.
Once the VBUS pin has been discharged, the
device will return to the Detect state regardless
of the PWR_EN control state.
Bypass
Switch
VDD
VS
VBUS
Port Power
Switch
VS
FIGURE 6-1:
VBUS
Bypass Switch.
While the VBUS bypass switch is active, the current
available to a portable device will be limited to IBUS_BYP
and the Attach Detection feature will be active.
6.1.2
ATTACH DETECTION
The primary Attach Detection feature is only active in
the Detect power state. When active, this feature constantly monitors the current load on the VBUS1 or VBUS2
pins. If the current drawn by a portable device is greater
than IDET_QUAL for longer than tDET_QUAL, an Attach
Detection event occurs. This will cause the A_DET#
status bits to be set.
Until the port power switch is enabled, the current available to a portable device will be limited to that used to
detect device attachment (IDET_QUAL). Once an Attach
Detection event occurs, the UCS2112 will wait for the
PWR_EN control to be enabled (if not already). When
PWR_EN is enabled and VS is above the threshold, the
UCS2112 will activate the VBUS port power switch and
operate in Active state.
 2015 Microchip Technology Inc.
DS20005424B-page 25
UCS2112
NOTES:
DS20005424B-page 26
 2015 Microchip Technology Inc.
UCS2112
7.0
USB PORT POWER SWITCH
To assure compliance to various charging
specifications, the UCS2112 contains a USB port
power switch that supports two current-limiting modes:
Trip and Constant current (variable slope). The current
limit (ILIM) is pin selectable (and may be updated via
the register set). The switch also includes soft start
circuitry and a separate short circuit current limit.
TABLE 7-1:
COMM_ILIM PWR_EN1
Pulldown
and
Resistor
PWR_EN2
(±1%)
Polarity
The port power switch is on in the Active state (except
when VBUS is discharging).
Note:
7.1
7.1.1
If a load that draws between 2 mA and 7 mA
is connected to the port power switch, a voltage ripple between 40-90 mVPP is observed
at the VBUS output. This behavior is normal
and it does not affect the charging process
when a portable device is connected.
Current Limiting
CURRENT LIMIT SETTING
The UCS2112 hardware set current limit, ILIM, can be
one of eight values. This resistor value is read once
upon UCS2112 power-up. The current limit can be
changed via the SMBus/I2C after power-up; however,
the programmed current limit cannot exceed the hardware set current limit. Unless connected to VDD, the
resistors in Table 7-1 are pull-down resistors.
At power-up, the communication mode (Stand-alone
or SMBus/I2C) and hardware current limit (ILIM) are
determined via the pull-down resistor (or pull-up resistor if connected to VDD) on the COMM_ILIM pin, as
shown in Table 7-1.
7.1.2
SHORT CIRCUIT OUTPUT
CURRENT LIMITING
Short circuit current limiting occurs when the output
current is above the selectable current limit (ILIMx).
This event will be detected and the current will immediately be limited (within tSHORT_LIM time). If the condition remains, the port power switch will flag an Error
condition and enter the Error state.
7.1.3
SOFT START
When the PWR_EN control changes states to enable the
port power switch, or an Attach Detection event occurs in
the Detect power state and the PWR_EN control is
already enabled, the UCS2112 invokes a soft start routine for the duration of the VBUS rise time (tR_BUS). This
soft start routine will limit current flow from VS into VBUS
while it is active. This circuitry will prevent current spikes
due to a step in the portable device current draw.
In the case when a portable device is attached while the
PWR_EN pin is already enabled, if the bus current
exceeds ILIM, the UCS2112 current limiter will respond
within a specified time (tSHORT_LIM) and will operate normally at this point. The CBUS capacitor will deliver the
extra current, if any, as required by the load change.
 2015 Microchip Technology Inc.
ILIM DECODE
ILIM (A)
Total ILIM
(A)
(Note 1)
GND
Active-High
0.53
0.53+0.53
10 kΩ
Active-High
0.96
0.96+096
12 kΩ
Active-High
1.07
1.07+1.07
15 kΩ
Active-High
1.28
1.28+1.28
18 kΩ
Active-High
1.6
1.6+1.6
22 kΩ
Active-High
2.13
2.13+2.13
27 kΩ
Active-High
2.67
2.67+2.67
33 kΩ
Active-High
3.2
3.2+3.2
47 kΩ
Active-Low
0.53
0.53+0.53
56 kΩ
Active-Low
0.96
0.96+0.96
68 kΩ
Active-Low
1.07
1.07+1.07
82 kΩ
Active-Low
1.28
1.28+1.28
100 kΩ
Active-Low
1.6
1.6+1.6
120 kΩ
Active-Low
2.13
2.13+2.13
150 kΩ
Active-Low
2.67
2.67+2.67
VDD
Active-Low
3.2
3.2+3.2
Note 1:
7.1.4
The total maximum current depends on
power dissipation characteristics of the
design (see Table 1-1).
CURRENT LIMITING MODES
The UCS2112 current limiting has two modes: trip and
constant current (variable slope). Either mode functions at all times when the port power switch is closed.
When operating in the Detect power state, the current
capacity at VBUS is limited to IBUS_BYP as described in
Section 6.1.1 “VBUS Bypass Switch”.
7.1.4.1
Trip Mode
When using trip current limiting, the UCS2112 USB
port power switch functions as a low resistance switch
and rapidly turns off if the current limit is exceeded.
While operating using trip current limiting, the VBUS
output voltage will be held relatively constant (equal to
the VS voltage minus the RON x IBUS current) for all
current values up to the ILIM.
If the current drawn by a portable device exceeds ILIM,
the following occurs:
1.
2.
3.
The port power switch will be turned off (Trip
action).
The UCS2112 will enter the Error state and
assert the ALERT# pin.
The fault handling circuitry will then determine
subsequent actions.
DS20005424B-page 27
UCS2112
Figure 7-1 shows operation of current limits in trip
mode with the shaded area representing the USB 2.0
specified VBUS range. Dashed lines indicate the port
power switch output will go to zero (e.g., trip) when
ILIM is exceeded. Note that operation at all possible
values of ILIM are shown in Figure 7-1 for illustrative
purposes only; in actual operation only one ILIM can be
active at any time.
ILIM (Amps)
Operating 0.53
Current
5.25
0.96 1.07 1.28
1.6
2.13
2.67
3.2
5
Figure 7-3 shows operation of current limits while
using CC mode. Unlike trip mode, once IBUS current
exceeds ILIM, operation continues at a reduced voltage
and increased current. Note that the shaded area representing the USB 2.0 specified VBUS range is now
restricted to an upper current limit of IBUS_R2MIN. Note
that the UCS2112 will heat up along each load line as
voltage decreases. If the internal temperature exceeds
the TREG or TTSD thresholds, the port power switch will
open. Also note that when the VBUS voltage is brought
low enough (below VBUS_MIN), the port power switch
will open.
4.75
= ILIM’s
ILIM (Amps)
0.53
Trip action
(ILIM = 0.53 A)
4
0.96
1.28
1.6 2.13
3.2
IBUS_R2MIN
5
Trip action
(ILIM = 3.2 A)
VBUS (Volts)
2.67
5.25
4.75
= ILIM’s
3
4
Constant resistance
IBUS operation line 4
(ILIM = 1.6 A)
Constant resistance
IBUS operation line 1
(ILIM = 0.53 A)
VBUS (Volts)
2
Power Switch Voltage and Current
Output go to Zero when ILIM is
Exceeded
1
3
2
0
0.96 1.07 1.28
0.53
0
1.6
2.13
2.67
1
3.2
CC Mode - Power switch current increases as voltage decreases
when ILIM is exceeded following constant resistance lines
IBUS (Amps)
FIGURE 7-1:
7.1.4.2
Current Limiting in Trip Mode.
Constant Current Limiting (Variable
Slope)
Constant current limiting is used when the current
drawn is greater than ILIM (and ILIM < 1.6A). In CC
mode, the port power switch allows the attached portable device to reduce VBUS output voltage to less than
the input VS voltage while maintaining current delivery.
The V/I slope depends on the user set ILIM value. This
slope is held constant for a given ILIM value.
This mode is specifically provided for devices that rely
on resistive means to reduce VBUS voltage for direct
battery charging or to allow portable devices a means
to “test” charger capacity. See Figure 7-2.
IBUS
VS
VBUS << VS
Power
Switch
ILIM
Control Loop
RSense
Temp
5 V DC
Battery
Charger
IC
VBAT
GND
UCS 2112
FIGURE 7-2:
Portable Device
Constant Current Example.
0
0.53
0
0.96
1.28
1.6
2.13
2.67
3.2
IBUS (Amps)
FIGURE 7-3:
7.2
Current Limiting in CC Mode.
USB Port Power Profiles
The UCS2112 combines the qualities of traditional
USB port power switches with USB port power profiles
set forth in the USB-IF BC1.2 specification. USB port
power profiles consist of distinct voltage-current operation regions defined by “keep-out” and “operation”
regions.
While operating in the CC mode of operation, the
UCS2112 provides voltage-current output operating
profiles that are specified by two keep-out regions.
If the current reaches the IBUS_R2MIN setting for longer
than tMASK, the UCS2112 enters the Error state and an
Overcurrent event is flagged.
If the VBUS voltage ever goes below the no operation
lower-voltage keep-out (VBUS_MIN) value for longer
than tMASK, the port power switch is disabled and a
keep-out violation is flagged (by setting the
MIN_KEEP_OUT status bit). This will cause the device
to enter the Error state.
Figure 7-4 illustrates the relationship between these
USB port power profile parameters.
DS20005424B-page 28
 2015 Microchip Technology Inc.
UCS2112
7.2.1
OPERATION WITHIN A USB PORT
POWER PROFILE
An attached device may be constrained to operate
within the boundaries of a USB port power profile by
setting the value of ILIM less than the USB port power
profile IBUS_R2MIN value. In this case, the port power
switch will be in Trip mode up until ILIM is exceeded. At
which point, the switch will transition into CC mode. If
the attached device reduces the output voltage to less
than VBUS_MIN, the switch will trip and terminate
charging.
7.2.2
OPERATION OUTSIDE OF A USB
PORT POWER PROFILE
An attached device may be allowed to operate outside
of the boundaries of a USB port power profile by setting the value of ILIM greater than the USB port power
profile IBUS_R2MIN value. This is the default operation
for all portable devices. In this case, the USB port
power switch will operate in Trip mode until the bus
current reaches the ILIM value. Once the ILIM value has
been exceeded, the port power switch will open and
terminate charging. Figure 7-5 illustrates an example
of current limiting in this configuration.
ILIM (Amps)
0.53
0.96
1.28
1.6 2.13
2.67
3.2
5.25
5
ILIM (Amps)
0.53
0.96
1.28
1.6
2.13
2.67
3.2
5.25
4.75
ILIM = 1.6A
5
4.75
ILIM = 2.67 A
4
IBUS_R2MIN = 1.6A
Port Power Profile
Operating Region
4
Port Power Profile
Operating Region
VBUS (Volts)
3
IBUS_R2MIN = 1. A
VBUS (Volts)
3
2
VBUS_MIN = 2.0 V
2
VBUS_MIN = 2.0 V
1
(Trip)
1
(Trip)
0
0.53
0
0.96
1.28
1.6
2.13
2.67
3.2
IBUS (Amps)
FIGURE 7-4:
Note:
ILIM < IBUS_R2MIN Example.
The CC mode of operation is possible only
up to 1.6A. As long as the value of ILIM is
less than the fixed port power profile
IBUS_R2MIN value, CC mode is possible.
Otherwise, the USB port power switch will
operate in trip mode operation.
 2015 Microchip Technology Inc.
0
0
0.53
0.96
1.28
1.6
2.13 2.67
3.2
IBUS (Amps)
FIGURE 7-5:
ILIM > IBUS_R2MIN Example.
DS20005424B-page 29
UCS2112
7.3
Thermal Management and Voltage
Protection
7.3.1.2
Thermal Shutdown
The UCS2112 utilizes two-stage internal thermal management. The first stage is Dynamic Thermal Management, and the second stage is Fixed Thermal
Shutdown.
The second stage of thermal management consists of
a hardware implemented thermal shutdown corresponding to the maximum allowable internal die temperature (TTSD). If the internal temperature exceeds
this value, the port power switches (both ports) will
immediately be turned off until the temperature is
below TTSD - TTSD_HYST.
7.3.1.1
7.4
7.3.1
THERMAL MANAGEMENT
Dynamic Thermal Management
For the first stage (active in both current-limiting
modes), referred to as Dynamic Thermal Management, the UCS2112 automatically adjusts port power
switch limits and modes to lower power dissipation
when the thermal regulation temperature value is
approached, as described in the following paragraphs.
If the internal temperature exceeds the TREG value,
the port power switch is opened, the current limit (ILIM)
will be lowered by one step and a timer is started
(tDC_TEMP). When this timer expires, the port power
switch is closed and the internal temperature will be
checked again. If it remains above the TREG threshold,
the UCS2112 will repeat this cycle (open port power
switch and reduce the ILIM setting by one step) until
ILIM reaches its minimum value.
If the UCS2112 is operating using Constant Current
Limiting (variable slope) and the ILIM setting has been
reduced to its minimum set point and the temperature
is still above TREG, the UCS2112 will switch to operating using trip current limiting. This will be done by
reducing the IBUS_R2MIN setting to 100 mA and restoring the ILIM setting to the value immediately below the
programmed setting (e.g., if the programmed ILIM is
2.13A, the value will be set to 1.6A). If the temperature
continues to remain above TREG, the UCS2112 will
continue this cycle (open the port power switch and
reduce the ILIM setting by one step).
If the UCS2112 internal temperature drops below
TREG - TREG_HYST, the UCS2112 will take action
based on the following:
1.
If the Current Limit mode changed from CC
mode to Trip mode, then a timer is started.
When this timer expires, the UCS2112 will reset
the port power switch operation to its original
configuration, allowing it to operate using Constant Current Limiting (variable slope).
2. If the Current Limit mode did not change from CC
mode to Trip mode, or was already operating in
Trip mode, the UCS2112 will reset the port power
switch operation to its original configuration.
If the UCS2112 is operating using Trip Current Limiting
and the ILIM setting has been reduced to its minimum
set point and the temperature is above TREG, the port
power switch will be closed and the current limit will be
held at its minimum setting until the temperature drops
below TREG - TREG_HYST.
DS20005424B-page 30
VBUS Discharge
The UCS2112 will discharge VBUS through an internal
100 resistor when at least one of the following conditions occurs:
• The PWR_EN control is disabled (triggered on the
inactive edge of the PWR_EN control).
• A portable device Removal Detection event is
flagged if the Attach/Removal Detect feature is
enabled (by default it is disabled).
• The VS voltage drops below a specified threshold
(VS_UVLO) that causes the port power switch to be
disabled.
• When commanded into the Sleep power state.
• Upon recovery from the Error state.
• When commanded via the SMBus in the Active
state.
• Any time the port power switch is activated after
the VBUS bypass switch has been on (i.e., whenever VBUS voltage transitions from being driven
from VDD to being driven from VS, such as going
from Detect to Active power state) if the
Attach/Removal Detect feature is enabled (by
default it is disabled).
• Any time the VBUS bypass switch is activated after
the port power switch has been on (i.e., going
from Active to Detect power state) if the
Attach/Removal Detect feature is enabled (by
default it is disabled).
When the VBUS discharge circuitry is activated at the
end of the tDISCHARGE time, the UCS2112 will confirm
that VBUS was discharged. If the VBUS voltage is not
below the V TEST level, a discharge error will be
flagged (by setting the DISCH_ERR(1/2) status bit)
and the UCS2112 will enter the Error state.
 2015 Microchip Technology Inc.
UCS2112
7.5
Charge Rationing Interactions
When charge rationing is active, regardless of the
specified behavior, the UCS2112 will function normally
until the charge rationing threshold is reached. Note
that charge rationing is only active when the UCS2112
is in the Active state, and it does not automatically
reset when a Removal or Attach Detection event
occurs. This allows charging of sequential portable
devices while charge is being rationed, which means
that the accumulated power given to several portable
devices will still be held to the stated rationing limit.
TABLE 7-2:
Changing the charge rationing behavior will have no
effect on the charge rationing data registers. If the
behavior is changed prior to reaching the charge
rationing threshold, this change will occur and be transparent to the user. When the charge rationing threshold
is reached, the UCS2112 will take action as shown in
Table 7-2. If the behavior is changed after the charge
rationing threshold has been reached, the UCS2112
will immediately adopt the newly programmed behavior, clearing the ALERT# pin and restoring switch
operation respectively (see Table 7-4).
CHARGE RATIONING BEHAVIOR
RATION_BEH
(1 or 2) <1:0>
Behavior
Actions taken
Notes
1
0
0
0
Report
0
1
Report and
Disconnect
(default)
1.
2.
ALERT# pin asserted.
Port power switch disconnected.
All bus monitoring is still active.
Toggling the PWR_EN control will cause the
device to change power states as defined by the
registers; however, the port power switch will
remain off until the rationing circuitry is reset. Furthermore, the bypass switch will not be turned on if
enabled via the Attach Detection.
1
0
Disconnect
and
Go to Sleep
1.
Port power switch disconnected.
Device will enter the
Sleep state.
All VBUS and VS monitoring will be stopped.
Toggling the PWR_EN control will have no effect
on the power state until the rationing circuitry is
reset.
1
Ignore
1
TABLE 7-3:
ALERT# pin asserted.
2.
Take no further action.
CHARGE RATIONING RESET BEHAVIOR
Behavior
Reset Actions
Report
1.
2.
3.
Reset the Total Accumulated Charge registers.
Clear the RATION status bit.
Release the ALERT# pin.
Report and Disconnect
1.
2.
3.
4.
Reset the Total Accumulated Charge registers.
Clear the RATION status bit.
Release the ALERT# pin.
Check the PWR_EN controls and enter the indicated power state if the controls
changed.
Disconnect and
Go to Sleep
1.
2.
3.
Reset the Total Accumulated Charge registers.
Clear the RATION status bit.
Check the PWR_EN controls and enter the indicated power state if the controls
changed.
Ignore
1.
2.
Reset the Total Accumulated Charge registers.
Clear the RATION status bit.
 2015 Microchip Technology Inc.
DS20005424B-page 31
UCS2112
TABLE 7-4:
EFFECTS OF CHANGING RATIONING BEHAVIOR AFTER THRESHOLD REACHED
Previous
Behavior
New Behavior
Ignore
Report
Actions Taken
Assert ALERT# pin.
Report and
Disconnect
1.
2.
Assert ALERT# pin.
Open port power switch. See the Report and Disconnect (default) in
Table 7-2.
Disconnect and
Go to Sleep
1.
2.
Open port power switch.
Enter the Sleep state. See the Disconnect and Go to Sleep in Table 7-2.
Report
Ignore
Report and
Disconnect
Release ALERT# pin.
Open port power switch. See the Report and Disconnect (default) in Table 7-2.
Disconnect and
Go to Sleep
1.
2.
3.
Release the ALERT# pin.
Open the port power switch.
Enter the Sleep state. See the Disconnect and Go to Sleep in Table 7-2.
Ignore
1.
2.
Release the ALERT# pin.
Check the PWR_EN controls and enter the indicated power state if the
controls changed.
Report
Check the PWR_EN controls and enter the indicated power state if the controls
changed.
Report and
Disconnect
Disconnect and
Go to Sleep
Disconnect
and go to
Sleep
1.
2.
Release the ALERT# pin.
Enter the Sleep state. See the Disconnect and Go to Sleep in Table 7-2.
Ignore
Check the PWR_EN controls and enter the indicated power state if the controls
changed.
Report
1.
2.
Assert the ALERT# pin.
Check the PWR_EN controls and enter the indicated power state if the
controls changed.
Report and
Disconnect
1.
2.
Assert the ALERT# pin.
Check the PWR_EN controls to determine the power state then enter that
state except that the port power switch and bypass switch will not be
closed.
If the RATION_EN control is set to ‘0’ prior to reaching
the charge rationing threshold, rationing will be disabled and the Total Accumulated Charge registers will
be cleared. If the RATION_EN control is set to ‘0’ after
the charge rationing threshold has been reached, the
following additional steps occur:
1.
2.
3.
RATION status bit will be cleared.
The ALERT# pin will be released if asserted by
the rationing circuitry and no other conditions
are present.
The PWR_EN controls are checked to determine the power state.
Setting the RATION_RST control to ‘1’ will automatically reset the Total Accumulated Charge registers to
00_00h. If this is done prior to reaching the charge
rationing threshold, the data will continue to be accumulated restarting from 00_00h. If this is done after the
charge rationing threshold is reached, the UCS2112
will take action as shown in Table 7-3.
DS20005424B-page 32
 2015 Microchip Technology Inc.
UCS2112
7.6
7.6.1
Fault Handling Mechanism
The UCS2112 has two modes for handling faults:
When the LATCH_SET bit is low, Auto-Recovery Fault
Handling is used. When an error condition is detected,
the UCS2112 will immediately enter the Error state
and assert the ALERT# pin. Independently from the
host controller, the UCS2112 will wait a preset time
(tCYCLE), check error conditions (tTST), and restore
Active operation if the error condition(s) no longer
exist. If all other conditions that may cause the
ALERT# pin to be asserted have been removed, the
ALERT# pin will be released. Short-Circuit
Auto-Recovery example in Figure 7-6.
• Latch (latch-upon-fault)
• Auto-recovery (automatically attempt to restore
the Active power state after a fault occurs).
If the SMBus is actively utilized, Auto-Recovery Fault
Handling is the default error handler as determined by
the LATCH_SET bit. Faults include overcurrent,
overvoltage (on VS), undervoltage (on VBUS),
back-voltage (VBUS to VS or VBUS to VDD), discharge
error, and maximum allowable internal die temperature
(TTSD) exceeded. Faults do not include keep-out
violations except VBUS_MIN.
tCYCLE
VBUS
AUTO-RECOVERY FAULT
HANDLING
tTST
tCYCLE
tTST
VTEST
tDISCHARGE
SHORT
applied.
IBUS
ITEST
Short Detected. VBUS
discharged. Enter
Error state.
FIGURE 7-6:
7.6.2
Wait tCYCLE.
Check short
condition. Short
still present.
Return to Error
State.
ITEST
Wait tCYCLE.
Check short
condition. Short
removed.
Return to
normal
operation.
Error Recovery.
LATCHED FAULT HANDLING
When the LATCH_SET bit is high, latch fault handling
is used. When an error condition is detected, the
UCS2112 will enter the Error power state and assert
the ALERT# (1 or 2) pin. Upon command from the host
controller (by toggling the PWR_EN (1, or 2) pin control from enabled to disabled or by clearing the ERR bit
via SMBus), the UCS2112 will check error conditions
once and restore Active operation if error conditions
no longer exist. If an error condition still exists, the
host controller is required to issue the command again
to check error conditions.
If the ALERT# pin is asserted and the interrupt status
registers (addresses 03h or 04h) are not read, the corresponding ALERT# pin remains asserted until the
corresponding PWR_EN pin is toggled.
If the ALERT# pin is asserted and the interrupt status
registers are read, the ALERT# pin will de-assert, but
the UCS will remain in error state until the ERR bit is
cleared via SMBus or the PWR_EN pin is toggled.
 2015 Microchip Technology Inc.
DS20005424B-page 33
UCS2112
8.0
SYSTEM MANAGEMENT BUS
PROTOCOL
In SMBus mode, the UCS2112 communicates with a
host controller, such as an Microchip PIC® microcontroller or hub, through the SMBus. The SMBus is a
two-wire serial communication protocol between a
computer host and its peripheral devices. A detailed
timing diagram is shown in Figure 1-1. Stretching of
the SMCLK signal is supported; however, the
UCS2112 will not stretch the clock signal.
8.1
SMBus Start Bit
8.6
SMBus Time-out
The UCS2112 includes an SMBus time-out feature. If
the clock is held at logic ‘0’ for tTIMEOUT, the device
can time out and reset the SMBus interface. The
SMBus interface can also reset if both the clock and
data lines are held at a logic ‘1’ for tIDLE_RESET. Communication is restored with a start condition.
The time-out function defaults to disabled. It can be
enabled by clearing the DIS_TO bit in the General
Configuration 3 register (see Register 9-9).
8.7
SMBus and I2C Compliance
The SMBus Start bit is defined as a transition of the
SMBus Data line from a logic ‘1’ state to a logic ‘0’
state while the SMBus Clock line is in a logic ‘1’ state.
The major difference between SMBus and I2C devices
is highlighted here. For complete compliance information, refer to the SMBus 2.0 specification and Application Note 14.0.
8.2
• UCS2112 supports I2C fast mode at 400 kHz. This
covers the SMBus maximum time of 100 kHz.
• The minimum frequency for SMBus communications is 10 kHz.
• The client protocol will reset if the clock is held low
longer than 30 ms. This time out functionality is
disabled by default in the UCS2112 and can be
enabled by clearing the DIS_TO bit. I2C does not
have a time out.
• Except when operating in Sleep, the client protocol will reset if both the clock and the data line are
logic ‘1’ for longer than 200 µs (idle condition).
This function is disabled by default in the
UCS2112 and can be enabled by clearing the
DIS_TO bit. I2C does not have an idle condition.
• I2C devices do not support the Alert Response
Address functionality (which is optional for SMBus).
• I2C devices support block read and write differently. I2C protocol allows for unlimited number of
bytes to be sent in either direction. The SMBus
protocol requires that an additional data byte indicating number of bytes to read/write is transmitted. The UCS2112 supports I2C formatting only.
SMBus Address and RD/WR Bit
The SMBus Address Byte consists of the 7-bit client
address followed by the RD/WR indicator bit. If this
RD/WR bit is a logic ‘0’, the SMBus Host is writing
data to the client device. If this RD/WR bit is a logic ‘1’,
the SMBus Host is reading data from the client device.
The UCS2112 with the order code UCS2112-1-V/G4
has the SMBus address 57h - 1010_111(r/w).
Customers should contact their distributor, representatives or field application engineer (FAE) for additional
SMBus addresses. Local sales offices are also available to help customers. A list of sales offices and locations is included in the back of this document.
8.3
SMBus Data Bytes
All SMBus Data bytes are sent most significant bit first
and composed of 8 bits of information.
8.4
SMBus ACK and NACK Bits
The SMBus client will acknowledge all data bytes that
it receives. This is done by the client device pulling the
SMBus Data line low after the 8th bit of each byte that
is transmitted. This applies to both the Write Byte and
Block Write protocols.
The Host will NACK (not acknowledge) the last data byte
to be received from the client by holding the SMBus data
line high after the 8th data bit has been sent. For the
Block Read protocol, the Host will ACK (acknowledge)
each data byte that it receives except the last data byte.
8.5
SMBus Stop Bit
The SMBus Stop bit is defined as a transition of the
SMBus Data line from a logic ‘0’ state to a logic ‘1’
state while the SMBus clock line is in a logic ‘1’ state.
When the UCS2112 detects an SMBus Stop bit and it
has been communicating with the SMBus protocol, it
will reset its client interface and prepare to receive further communications.
DS20005424B-page 34
8.8
SMBus Protocols
The UCS2112 is SMBus 2.0-compatible and supports
Send Byte, Read Byte, Block Read, Receive Byte as
valid protocols as shown below. The UCS2112 also
supports the I2C block read and block write protocols.
The device supports Write Byte, Read Byte, and Block
Read/Block Write. All of the below protocols use the
convention in Table 8-1.
TABLE 8-1:
SMBUS PROTOCOL
Data Sent to Device
Data Sent to the Host
Data sent
Data sent
 2015 Microchip Technology Inc.
UCS2112
8.9
SMBus Write Byte
The Write Byte is used to write one byte of data to a
specific register as shown in Table 8-2.
TABLE 8-2:
WRITE BYTE PROTOCOL
START
Slave
Address
WR
ACK
Reg. Addr.
ACK
Register Data
ACK
STOP
1→0
YYYY_YYY
0
0
XXh
0
XXh
0
0→1
8.10
SMBus Read Byte
The Read Byte protocol is used to read one byte of
data from the registers as shown in Table 8-3.
TABLE 8-3:
READ BYTE PROTOCOL
START
Slave Address
WR
ACK
Register Address
ACK
1→0
YYYY_YYY
0
0
XXh
0
START
Slave Address
RD
ACK
Register Data
NACK
STOP
1 →0
YYYY_YYY
1
0
XXh
1
0→1
8.11
Block Write
The Block Write is used to write multiple data bytes to
a group of contiguous registers, as shown in Table 8-4.
It is an extension of the Write Byte Protocol.
The Block Write and Block Read protocols
require that the address pointer be automatically incremented. For a write command, the address pointer will be
automatically incremented when the ACK
is sent to the host. There are no over or
under bound limit checking and the
address pointer will wrap around from FFh
to 00h if necessary
Note:
TABLE 8-4:
START
1→0
8.12
BLOCK WRITE PROTOCOL
Slave Address
YYYY_YYY
WR
0
ACK
Repeat N Times
Register
Address
ACK
XXh
0
0
STOP
Register Data
ACK
XXh
0
0→1
Block Read
The Block Read is used to read multiple data bytes
from a group of contiguous registers, as shown in
Table 8-5. It is an extension of the Read Byte Protocol.
TABLE 8-5:
BLOCK READ PROTOCOL
START
Slave Address
WR
ACK
Register
Address
ACK
1→0
YYYY_YYY
0
0
XXh
0
START
Slave Address
RD
ACK
Repeat N Times
1→0
YYYY_YYY
 2015 Microchip Technology Inc.
1
0
Register Data NACK
Register Data
ACK
XXh
0
XXh
1
STOP
0→1
DS20005424B-page 35
UCS2112
8.13
SMBus Send Byte
The Send Byte protocol is used to set the internal
address register pointer to the correct address location.
No data is transferred during the Send Byte protocol as
shown in Table 8-6.
TABLE 8-6:
SEND BYTE PROTOCOL
START
Slave Address
WR
ACK
Register Address
ACK
STOP
1→0
YYYY_YYY
0
0
XXh
0
0→1
8.14
SMBus Receive Byte
The Receive Byte protocol is used to read data from a
register when the internal register address pointer is
known to be at the right location (e.g. set via Send
Byte). This is used for consecutive reads of the same
register as shown in Table 8-7.
TABLE 8-7:
RECEIVE BYTE PROTOCOL
START
Slave Address
RD
ACK
Register Data
NACK
STOP
1→0
YYYY_YYY
1
0
XXh
1
0→1
8.14.1
STAND-ALONE OPERATING MODE
Stand-alone mode allows the UCS2112 to operate
communications.
without
active
SMBus/I2C
Stand-alone mode can be enabled by connecting a
pull-down resistor greater or equal to 47 k on the
COMM_ILIM pin as shown in Table 5-3.The SMCLK
pin should be tied to ground in this mode.
DS20005424B-page 36
 2015 Microchip Technology Inc.
UCS2112
9.0
REGISTER DESCRIPTION
The registers shown in Table 9-1 are accessible
through the SMBus or I2C. An entry of ‘—’ indicates
that the bit is not used. Writing to these bits will have no
effect and reading these bits will return ‘0’. Writing to a
reserved bit may cause unexpected results and reading from a reserved bit will return either ‘1’ or ‘0’ as indicated in the bit description. While in the Sleep state, the
UCS2112 will retain configuration and charge rationing
data as indicated in the text. If a register does not indicate that data will be retained in the Sleep power state,
this information will be lost when the UCS2112 enters
the Sleep power state.
TABLE 9-1:
REGISTER SET IN HEXADECIMAL ORDER
Register
Address
Register Name
R/W
Default
Value
Page
No.
00h
Port 1 Current Measurement
R
Stores the current measurement for port 1
00h
38
01h
Port 2 Current Measurement
02h
Load Share VBUS Port Status
R
Stores the current measurement for port 2
00h
38
R
Indicates Load ShareVBUS Port and general
status
00h
39
03h
Interrupt Status1
See Text
Indicates why ALERT# pin asserted for port 1
00h
40
04h
Interrupt Status2
See Text
Indicates why ALERT# pin asserted for port 2
00h
42
Function
0Fh
General Status1
R/R-C
Indicates General Status for port 1
00h
43
10h
General Status2
R/R-C
Indicates General Status for port 2
00h
44
11h
General Configuration1
R/W
Controls basic functionality for port 1
06h
45
12h
General Configuration2
R/W
Controls basic functionality for port 2
02h
46
13h
General Configuration3
R/W
Controls other functionality
60h
47
14h
Current Limit
R/W
Controls/Displays MAX Current Limit per port
00h
48
15h
Auto-recovery Configuration
R/W
Controls the Auto-recovery functionality
2Ah
49
16h
Port 1 Total Accumulated
Charge High Byte
R
Stores the total accumulated charge
delivered high byte, Port 1
00h
50
17h
Port 1 Total Accumulated
Charge Middle High Byte
R
Stores the total accumulated charge
delivered middle high byte, Port 1
00h
50
18h
Port 1 Total Accumulated
Charge Middle Low Byte
R
Stores the total accumulated charge
delivered middle low byte, Port 1
00h
50
19h
Port 1 Total Accumulated
Charge Low Byte
R
Stores the total accumulated charge
delivered low byte, Port 1
00h
50
1Ah
Port 2 Total Accumulated
Charge High Byte
R
Stores the total accumulated charge
delivered high byte, Port 2
00h
51
1Bh
Port 2 Total Accumulated
Charge Middle High Byte
R
Stores the total accumulated charge
delivered middle high byte, Port 2
00h
51
1Ch
Port 2 Total Accumulated
Charge Middle Low Byte
R
Stores the total accumulated charge
delivered middle low byte, Port 2
00h
51
1Dh
Port 2 Total Accumulated
Charge Low Byte
R
Stores the total accumulated charge
delivered low byte, Port 2
00h
51
1Eh
Port 1 Charge Rationing
Threshold High Byte
R/W
Sets the maximum allowed charge that will
be delivered to Port 1
FFh
52
1Fh
Port 1 Charge Rationing
Threshold Low Byte
R/W
Sets the maximum allowed charge that will
be delivered to Port 1
FFh
52
 2015 Microchip Technology Inc.
DS20005424B-page 37
UCS2112
TABLE 9-1:
REGISTER SET IN HEXADECIMAL ORDER (CONTINUED)
Register
Address
Register Name
R/W
Function
Default
Value
Page
No.
20h
Port 2 Charge Rationing
Threshold High Byte
R/W
Sets the maximum allowed charge that will
be delivered to Port 2
FFh
52
21h
Port 2 Charge Rationing
Threshold Low Byte
R/W
Sets the maximum allowed charge that will
be delivered to Port 2
FFh
52
22h
Ration Configuration
R/W
Controls Charge Ration Functionality
11h
53
23h
Port 1 Current Limit Behavior
R/W
Controls the Current Limiting Behavior (CC
Mode Region 2) for Port 1
96h
54
24h
Port 2 Current Limit Behavior
R/W
Controls the Current Limiting Behavior (CC
Mode Region 2) for Port 2
96h
54
FDh
Product ID
E0hE1h
55
R
Stores a fixed value that identifies each
product
FEh
Manufacturer ID
R
Stores a fixed value that identifies Microchip
5Dh
55
FFh
Revision
R
Stores a fixed value that represents the
revision number
81h
55
9.1
Current Measurement Register
The Current Measurement register stores the measured current value delivered to the portable device
(IBUS). This value is updated continuously while the
device is in the Active power state.
REGISTER 9-1:
R-0
PORTS 1 AND 2 CURRENT MEASUREMENT REGISTERS
(ADDRESSES 00H, 01H)
R-0
R-0
R-0
R-0
R-0
R-0
R-0
CM(x)<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7:0
Note 1:
2:
x = Bit is unknown
CM(x)<7:0>: Port X Current Measurement, where x=1 or 2 (address 00h for Port 1 and address 01h for
Port 2).
The bit weights are in mA,1 LSB = 13.3 mA (maximum value is 255 LSB corresponding to 3.4A).
This data will be cleared when the device enters the Sleep or Detect states. This data will also be cleared
whenever the port power switch is turned off (or any time that VBUS is discharged).
DS20005424B-page 38
 2015 Microchip Technology Inc.
UCS2112
9.2
Status Registers
The Status registers store bits that indicate error
conditions as well as Attach Detection and Removal
Detection.
REGISTER 9-2:
R-0
ALERT2_PIN
VBUS PORT STATUS REGISTER (ADDRESS 02H)
R-0
ALERT1_PIN
R-0
CC_MODE2
R-0
U-0
U-0
R-0
R-0
CC_MODE1
—
—
ADET2_PIN
ADET1_PIN
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ALERT2_PIN: Reflects the status of the ALERT#2 pin. This bit is set and cleared as the ALERT#2 pin
changes states.
1 = ALERT#2 Pin asserted (logic low)
0 = ALERT#2 Pin not asserted
bit 6
ALERT1_PIN: Reflects the status of the ALERT#1 pin. This bit is set and cleared as the ALERT#1 pin
changes states.
1 = ALERT#1 Pin asserted (logic low)
0 = ALERT#1 Pin not asserted
bit 5
CC_MODE2: Port2 Constant Current Mode State
1 = Port 2 in Constant Current mode
0 = Port 2 operating normally
bit 4
CC_MODE1: Port1 Constant Current Mode State
1 = Port 1 in Constant Current mode
0 = Port 1 operating normally
bit 3-2
Unimplemented
bit 1
ADET2:_PIN Reflects the status of the A_DET#2 pin. When set, indicates that the A_DET#2 pin is
asserted low. This bit is set and cleared as the A_DET#2 pin changes states.
1 = A_DET#2 pin is asserted (logic low)
0 = A_DET#2 pin is not asserted
bit 0
ADET1_PIN: Reflects the status of the A_DET#1 pin. When set, indicates that the A_DET#1 pin is
asserted low. This bit is set and cleared as the A_DET#1 pin changes states.
1 = A_DET#1 pin is asserted (logic low)
0 = A_DET#1 pin is not asserted
 2015 Microchip Technology Inc.
DS20005424B-page 39
UCS2112
REGISTER 9-3:
INTERRUPT STATUS 1 REGISTER (ADDRESS 03H)
R/W-0
R/C-0
R/C-0
R/C-0
R/C-0
R/C-0
R/C-0
R/C-0
ERR1
DISCH_ERR1
RESET
KEEP_OUT1
TSD
OV_VOLT
BACK_V1
OV_LIM1
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ERR1: Error Port 1 - Indicates that an error was detected on the VBUS1 pin and the device has entered
the Error state. Writing this bit to ‘0’ will clear the Error state and allows the device to be returned to the
Active state. When written to ‘0’, all error conditions are checked. If all error conditions have been
removed, the UCS2112 returns to the Active state. This bit is set automatically by the UCS2112 when
the Error state is entered. If any other bit is set in the Interrupt Status register (03h), the device will not
leave the Error state.
This bit is cleared automatically by the UCS2112 if the Auto-recovery fault handling functionality is active
and no error conditions are detected. Likewise, this bit is cleared when the PWR_EN1 control is disabled
(Note 1).
1 = Port 1 in Error State.
0 = Port 1 in Active State (no errors detected).
bit 6
DISCH_ERR1: Discharge Error Port 1 - indicates the device was unable to discharge Port1. This bit will
be cleared when read if the error condition has been removed or if the ERR bit is cleared. This bit will
cause the ALERT#1 pin to be asserted and the device to enter the Error state.
1 = UCS2112 was unable to Discharge VBUS1.
0 = No VBUS1 discharge error.
bit 5
RESET: Indicates that the UCS2112 has just been reset and should be re-programmed. This bit will be
set at power-up. This bit is cleared when read or when the PWR_EN control is toggled. The ALERT#
pins are not asserted when this bit is set. This data is retained in the Sleep state.
1 = UCS2112 has just been reset.
0 = Reset did not occur.
bit 4
KEEP_OUT1: Port 1 Minimum Keep-out region - Indicates that the V-I output on the VBUS1 pin has
dropped below VBUS_MIN. This bit will be cleared when read if the error condition has been removed or
if the ERR1 bit is cleared. This bit will cause the ALERT#1 pin to be asserted and the device to enter the
Error state.
1 = VBUS1 < VBUS_MIN
0 = VBUS1 > VBUS_MIN
bit 3
TSD: Thermal Shutdown - Indicates that the internal temperature has exceeded TTSD threshold and the
device has entered the Error state. This bit will be cleared when read if the error condition has been
removed or if the ERR1 bit is cleared. This bit will cause the ALERT#1and ALERT#2 pins to be asserted
and the device to enter the Error state.
1 = Thermal Shutdown Temperature reached.
0 = Internal temperature < TTSD
bit 2
OV_VOLT: VS Overvoltage Indicates that the VS voltage has exceeded the VS_OV threshold, and the
device has entered the Error state. This bit will be cleared when read if the error condition has been
removed or if the ERR1 bit is cleared. This bit will cause the ALERT#1 and ALERT#2 pins to be asserted
and the device to enter the Error state.
1 = VS > VS_OV
0 = VS < VS_OV
DS20005424B-page 40
 2015 Microchip Technology Inc.
UCS2112
REGISTER 9-3:
INTERRUPT STATUS 1 REGISTER (ADDRESS 03H) (CONTINUED)
bit 1
BACK_V1: Back-Bias Voltage Port 1 - Indicates that the VBUS1 voltage has exceeded the VS or VDD
voltages by more than 150 mV. This bit will be cleared when read if the error condition has been removed
or if the ERR1 bit is cleared. This bit will cause the ALERT#1 pin to be asserted and the device to enter
the Error state.
1 = VBUS1 > VS, or VBUS1 > VDD by more than 150 mV.
0 = VBUS1 voltage has not exceeded the VS and VDD voltages by more than 150 mV.
bit 0
OV_LIM1: Over Current Limit Port 1 -Indicates that the IBUS current has exceeded both the ILIM threshold and the IBUS_R2MIN threshold settings for VBUS1. This bit will be cleared when read if the error condition has been removed or if the ERR1 bit is cleared. This bit will cause the ALERT#1 pin to be asserted
and the device to enter the Error state.
1 = Current Limit for Port 1 exceeded
0 = Current Limit for Port 1 not exceeded
Note 1:
Note that the ERR1 bit does not necessarily reflect the ALERT#1 pin status. The ALERT#1 pin may be
cleared or asserted without the ERR1 bit changing states.
 2015 Microchip Technology Inc.
DS20005424B-page 41
UCS2112
REGISTER 9-4:
INTERRUPT STATUS 2 REGISTER (ADDRESS 04H)
R/W-0
R/C-0
R-0
R/C-0
R/C-0
U-0
R/C-0
R/C-0
ERR2
DISCH_ERR2
VS_LOW
KEEP_OUT2
TREG
—
BACK_V2
OV_LIM2
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ERR2: Error Port 2 - Indicates that an error was detected on the VBUS1 pin and the device has entered
the Error state. Writing this bit to a ‘0’ will clear the Error state and allows the device to be returned to
the Active state. When written to ‘0’, all error conditions are checked. If all error conditions have been
removed, the UCS2112 returns to the Active state. This bit is set automatically by the UCS2112 when
the Error state is entered. If any other bit is set in the Interrupt Status register (04h), the device will not
leave the Error state. This bit is cleared automatically by the UCS2112 if the auto-recovery fault handling
functionality is active and no error conditions are detected. Likewise, this bit is cleared when the
PWR_EN2 control is disabled (Note 1).
1 = Port 2 in Error State.
0 = Port 2 in Active State (no errors detected).
bit 6
DISCH_ERR2: Discharge Error Port 2 - indicates the device was unable to discharge Port2. This bit will
be cleared when read if the error condition has been removed or if the ERR bit is cleared. This bit will
cause the ALERT#2 pin to be asserted and the device to enter the Error state.
1 = Device was unable to Discharge VBUS2.
0 = No VBUS2 discharge error.
bit 5
VS_LOW: Indicates that the VS voltage has fallen below the VS_UVLO threshold and both VBUS1 and
VBUS2 port power switches are held off. This bit is cleared automatically when the VS voltage is above
the VS_UVLO threshold.
1 = VS voltage has fallen below the VS_UVLO.
0 = VS voltage is above VS_UVLO.
bit 4
KEEP_OUT2: Port 2 Minimum Keep-out region - Indicates that the V-I output on the VBUS2 pin has
dropped below VBUS_MIN. This bit will be cleared when read if the error condition has been removed or
if the ERR2 bit is cleared. This bit will cause the ALERT#2 pin to be asserted and the device to enter the
Error state.
1 = VBUS2 < VBUS_MIN
0 = VBUS2 > VBUS_MIN
bit 3
TREG: Thermal Regulation - Indicates that the internal temperature has exceeded TREG and that the
current limit has been reduced. This bit is cleared when read and will not cause the ALERT#1 and
ALERT#2 pins to be asserted unless the ALERT_LINK bit is set.
1 = Internal temperature > TREG
0 = Internal temperature < TREG
bit 2
Unimplemented: Read as '0'
bit 1
BACK_V2: Back-Bias Voltage Port 2 - Indicates that the VBUS2 voltage has exceeded the VS or VDD
voltages by more than 150 mV. This bit will be cleared when read if the error condition has been removed
or if the ERR2 bit is cleared. This bit will cause the ALERT#2 pin to be asserted and the device to enter
the Error state.
1 = VBUS2 > VS, or VBUS2 > VDD by more than 150 mV.
0 = VBUS2 voltage has not exceeded the VS and VDD voltages by more than 150 mV.
bit 0
OV_LIM2: Overcurrent Limit Port 2 - Indicates that the IBUS current has exceeded both the ILIM threshold
and the IBUS_R2MIN threshold settings for VBUS2. This bit will be cleared when read if the error condition
has been removed or if the ERR2 bit is cleared. This bit will cause the ALERT#2 pin to be asserted and
the device to enter the Error state.
1 = Current Limit for Port 2 exceeded
0 = Current Limit for Port 2 not exceeded.
Note 1:
Note that the ERR2 bit does not necessarily reflect the ALERT#2 pin status. The ALERT#2 pin may be cleared or
asserted without the ERR2 bit changing states.
DS20005424B-page 42
 2015 Microchip Technology Inc.
UCS2112
REGISTER 9-5:
GENERAL STATUS 1 REGISTER (ADDRESS 0FH)
R/C-0
U-x
U-x
RATION1
—
—
R-0
R-0
R/C-0
CC_MODE1 PWR_EN1_CON LOW_CUR1
R/C-0
R-0
REM1
ADET1
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
RATION1: Indicates the state of Port 1 Rationing. This bit is cleared when read, or cleared automatically
when the RATION_RST1 bit is set or the RATION_EN1 bit is cleared.
1 = Port 1 has delivered the programmed mAh of current
0 = Port 1 has not delivered the programmed mAh of current
bit 6-5
Unimplemented
bit 4
CC_MODE1: Indicates whether Port 1 has entered CC mode.
1 = Port 1 is in CC mode
0 = Port 1 not in CC mode
bit 3
PWR_EN1_CON: Reflects the PWR_EN control state. This bit is set and cleared automatically with the
logic expression (PWR_EN1 pin OR PWR_EN1S).
1 = Port 1 Power Enable is set
0 = Port 1 Power Enable is clear
bit 2
LOW_CUR1: Indicates if the portable device charge current is below the 13.3 mA threshold on the
VBUS1 and may be finished charging. This bit is cleared when read and will cause the ALERT#1 pin to
be asserted if the ALERT_LINK1 bit is set.
1 = Port 1 charging current less than threshold
0 = Port 1 charging current above threshold
bit 1
REM1: Removal Detection Port1 - Indicates if a Removal Detection event has occurred and there is no
longer a portable device present on the VBUS1 pin. This bit is cleared when read and will not cause the
ALERT#1 pin to be asserted.
1 = Removal Detection occurred
0 = No Removal Detection
bit 0
ADET1: Attach Detection Port1 - Indicates that an Attach Detection event has occurred on the VBUS1
pins and there is a new portable device present. Asserts the A_DET#1 pin. This bit is set and cleared
as the A_DET#1 pin changes.
1 = Attach Detection event has occurred. A_DET#1 pin asserted
0 = No Attach Detection event
 2015 Microchip Technology Inc.
DS20005424B-page 43
UCS2112
REGISTER 9-6:
GENERAL STATUS 2 REGISTER (ADDRESS 10H)
R/C-0
U-x
U-x
RATION2
—
—
R-0
R-0
R/C-0
CC_MODE2 PWR_EN2_CON LOW_CUR2
R/C-0
R-0
REM2
ADET2
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
RATION2: Indicates the state of Port 2 Rationing. This bit is cleared when read, or cleared automatically
when the RATION_RST2 bit is set or the RATION_EN2 bit is cleared.
1 = Port 2 has delivered the programmed mAh of current
0 = Port 2 has not delivered the programmed mAh of current
bit 6-5
Unimplemented
bit 4
CC_MODE2: Indicates whether Port 2 has entered CC mode.
1 = Port 2 is in CC mode
0 = Port 2 not in CC mode
bit 3
PWR_EN2_CON: Reflects the PWR_EN control state. This bit is set and cleared automatically with the
logic expression (PWR_EN2 pin OR. PWR_EN2S).
1 = Port 2 Power Enable is set
0 = Port 2 Power Enable is clear
bit 2
LOW_CUR2: Indicates if the portable device charge current is below the 13.3 mA threshold on the
VBUS2 and may be finished charging. This bit is cleared when read and will cause the ALERT#2 pin to
be asserted if the ALERT_LINK2 bit is set.
1 = Port 2 charging current less than threshold
0 = Port 2 charging current above threshold
bit 1
REM2: Removal Detection Port2 - Indicates if a Removal Detection event has occurred and there is no
longer a portable device present on the VBUS1 pin. This bit is cleared when read and will not cause the
ALERT#2 pin to be asserted.
1 = Removal Detection occurred
0 = No Removal Detection
bit 0
ADET2: Attach Detection Port2 - indicates that an Attach Detection event has occurred on the VBUS2
pins and there is a new portable device present. Asserts the A_DET#2 pin. This bit is set and cleared
as the A_DET#2 pin changes.
1 = Attach Detection event has occurred. A_DET#2 pin asserted
0 = No Attach Detection event
DS20005424B-page 44
 2015 Microchip Technology Inc.
UCS2112
9.3
Configuration Registers
The Configuration registers control basic device
functionality. The contents of these registers are
retained in Sleep.
REGISTER 9-7:
GENERAL CONFIGURATION 1 REGISTER (ADDRESS 11H)
R/W-0
R/W-0
R/W-0
R/W-0
ALERT1_MASK
ALERT1_LINK
DSCHG1
PWR_EN1S
R/W-0
R/W-1
DISCHG_TIME<1:0>
R/W-1
R/W-0
ATT_TH1<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ALERT1_MASK: Mask errors for all interrupts in Register 9-3 except OV_LIM1 and TSD.
1 = The ALERT#1 pin will only assert if a OV_LIM1 or TSD is detected.
0 = The ALERT#1 pin will be asserted if an error condition or indicator event is detected.
bit 6
ALERT1_LINK: Links the ALERT#1 pin to be asserted when the LOW_CUR1 bit is set.
1 = The ALERT#1 pin will be asserted if the LOW_CUR1 indicator bit is set.
0 = The ALERT#1 pin will not be asserted if the LOW_CUR1 indicator bit is set.
bit 5
DSCHG1: Forces the VBUS1 to be reset and discharged when the UCS2112 is in the Active state.
Writing this bit to a logic ‘1’ will cause the port power switch to be opened and the discharge circuitry
to activate and discharge VBUS. Actual discharge time is controlled by DISCHG_TIME<1:0>. This
bit is self-clearing.
1 = VBUS1 discharge initiated.
0 = Port 1 not in discharge
bit 4
PWR_EN1S: Power Enable Port 1 override - This bit is OR’ed with the PWR_EN1 pin. Thus, if the
polarity is set to active-high, either the PWR_EN1 pin or this bit must be ‘1’ to enable the port power
switch.
bit 3-2
DISCHG_TIME<1:0>: Discharge time Port 1 - sets tDISCHARGE. The discharge time value is the
same for both ports.
00 = 100 ms
01 = 200 ms
10 = 300 ms
11 = 400 ms
bit 1-0
ATT_TH1<1:0>: Attach Detection Threshold Port 1 - determines the current draw needed to determine an Attach event has occurred. Also controls the Removal Detection current level (Note 1).
00 = 200 µA Attach/100 µA Removal
01 = 400 µA Attach/300 µA Removal
10 = 800 µA Attach/700 µA Removal
11 = 1000 µA Attach/900 µA Removal
Note 1:
The removal threshold is different when operating in the Active power state versus when operating in the
Detect power state.
 2015 Microchip Technology Inc.
DS20005424B-page 45
UCS2112
REGISTER 9-8:
GENERAL CONFIGURATION 2 REGISTER (ADDRESS 12H)
R/W-0
R/W-0
ALERT2_MASK ALERT2_LINK
R/W-0
R/W-0
U-0
U-0
DSCHG2
PWR_EN2S
—
—
R/W-1
R/W-0
ATT_TH2
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
ALERT2_MASK: Mask errors for all interrupts in Register 9-4 except OV_LIM2 and TSD.
1 = The ALERT#2 pin will only assert if a OV_LIM2 or TSD is detected.
0 = The ALERT#2 pin will be asserted if an error condition or indicator event is detected.
bit 6
ALERT2_LINK: Links the ALERT#2 pin to be asserted when the LOW_CUR2 or TREG bits are set.
1 = The ALERT#2 pin will be asserted if the LOW_CUR2 or TREG indicator bit is set.
0 = The ALERT#2 pin will not be asserted if the LOW_CUR2 or TREG indicator bit is set.
bit 5
DSCHG2: Forces the VBUS2 to be reset and discharged when the UCS2112 is in the Active state.
Writing this bit to a logic ‘1' will cause the port power switch to be opened and the discharge circuitry
to activate to discharge VBUS. Actual discharge time is controlled by DISCHG_TIME<1:0>. This bit
is self-clearing.
1 = VBUS2 discharge initiated.
0 = Port 2 not in discharge
bit 4
PWR_EN2S: Power Enable Port 2 override - This bit is OR’ed with the PWR_EN2 pin. Thus, if the
polarity is set to active-high, either the PWR_EN2 pin or this bit must be ‘1’ to enable the port power
switch.
bit 3-2
Unimplemented
bit 1-0
ATT_TH2<1:0>: Attach Detection Threshold Port 2 - determines the current draw needed to determine an Attach event has occurred. Also controls the Removal Detection current level (Note 1).
00 = 200 µA Attach/100 µA Removal
01 = 400 µA Attach/300 µA Removal
10 = 800 µA Attach/700 µA Removal
11 = 1000 µA Attach/900 µA Removal
Note 1:
The removal threshold is different when operating in the Active power state versus when operating in the Detect power
state.
DS20005424B-page 46
 2015 Microchip Technology Inc.
UCS2112
REGISTER 9-9:
GENERAL CONFIGURATION 3 REGISTER (ADDRESS 13H)
R/W-0
R/W-1
R/W-1
PIN_IGN
ATT_DIS
DIS_TO
R-0
R-0
PWR_STATE<1:0>
R/W-0
U-0
U-0
BOOST
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
C = Clear on Read
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
PIN_IGN: Ignores the PWR_EN1 and PWR_EN2 pin states when determining the power state. This bit
is retained in Sleep.
1 = PWR_EN1 and PWR_EN2 pin states are ignored.
0 = Power state is determined by the OR'd combination of the PWR_EN1 and PWR_EN2 pins states
and the corresponding PWR_EN1S and PWR_EN2S bit states.
bit 6
ATT_DIS: Attach Detect Disable - Disables the Attach and Removal Detection feature and affects the
power state (see Table 5-2). Setting this bit to 1 forces Active state provided the PWR_EN 1/2 control is
enabled.
1 = Attach/Removal Detection disabled.
0 = Attach/Removal Detection enabled.
bit 5
DIS_TO: Disable Time Out - Disables the SMBus time out feature.
1 = Time out disabled
0 = Time out enabled
bit 4-3
PWR_STATE<1:0>: Current Power State - These bits indicate the current Power State. See Note 1
00 =SLEEP
01 =DETECT
10 =ACTIVE
11 =ERROR
bit 2
BOOST: Indicates that the IBUS current is higher than IBOOST on VBUS1 or VBUS2 (bit is OR’ed).
1 = IBUS has exceeded IBOOST on either or both ports
0 = IBUS is less than IBOOST on either port individually
bit 1-0
Note 1:
Unimplemented
Accessing the SMBus/I2C™ causes the UCS2112 to leave the Sleep state. As a result, the PWR_STATE<1:0> bits will
never read as 00b.
 2015 Microchip Technology Inc.
DS20005424B-page 47
UCS2112
9.4
Current Limit Register
The Current Limit register controls the ILIM used by the
port power switch. The default setting is based on the
resistor on the COMM_ILIM pin and this value cannot
be changed to be higher than hardware set value. The
contents of this register are retained in Sleep.
REGISTER 9-10:
CURRENT LIMIT REGISTER (ADDRESS 14H)
U-0
U-0
—
—
R/W-0
R/W-0
R/W-0
R/W-0
ILIM_PORT2<2:0>
R/W-0
R/W-0
ILIM_PORT1<2:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-6
Unimplemented: Read as ‘0’'
bit 5-3
ILIM_PORT2<2:0>: Sets the ILIM value for port 2.
000 = 0.53A
001 = 0.96A
010 = 1.07A
011 = 1.28A
100 = 1.6A
101 = 2.13A
110 =2.67A
111 =3.2A
bit 2-0
ILIM_SW<2:0>: Sets the ILIM value for port 1.
000 = 0.53A
001 = 0.96A
010 = 1.07A
011 = 1.28A
100 = 1.6A
101 = 2.13A
110 = 2.67A
111 = 3.2A
DS20005424B-page 48
x = Bit is unknown
 2015 Microchip Technology Inc.
UCS2112
9.5
Auto-Recovery Register
The contents of this register are retained in Sleep.
The Auto-Recovery Configuration register sets the
parameters used when the Auto-recovery fault handling algorithm is invoked. Once the Auto-recovery fault
handling algorithm has checked the overtemperature
and back-drive conditions, it will set the ILIM value to
ITEST and then turn on the port power switch and start
the tTST timer. If, after the timer has expired, the VBUS
voltage is less than VTEST, then it is assumed that a
short-circuit condition is present and the Error state is
restarted for Auto Recovery.
REGISTER 9-11:
R/W-0
AUTO RECOVERY CONFIGURATION REGISTER (ADDRESS 15H)
R/W-0
LATCHS
R/W-1
TCYCLE<2:0>
R/W-0
R/W-1
R/W-0
TTST<1:0>
R/W-1
R/W-0
VTST_SW<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
LATCHS: Latch Set - Controls the fault-handling routine that is used in the case that an error is detected.
1 = Error state will be latched. In order for the UCS2112 to return to normal Active state, the ERR bit
must be cleared by the user.
0 = The UCS2112 will automatically retry when an error condition is detected.
bit 6-4
TCYCLE<2:0>: Defines the delay (tCYCLE) after the Error state is entered before the Auto-recovery fault
handling algorithm is started as shown below.
000 = 15 ms
001 = 20 ms
010 = 25 ms
011 = 30 ms
100 = 35 ms
101 = 40 ms
110 = 45 ms
111 = 50 ms
bit 3-2
TTST<1:0>: Retry Duration timer - Sets the tTST as shown below.
00 = 10 ms
01 = 15 ms
10 = 20 ms
11 = 25 ms
bit 1-0
VTST_SW: Short-circuit Voltage Threshold VTEST voltage threshold that must be crossed during retries
to declare the short removed.
00 = 250 mV
01 = 500 mV
10 = 750 mV
11 = 1000 mV
 2015 Microchip Technology Inc.
DS20005424B-page 49
UCS2112
9.6
Total Accumulated Charge Registers
The Total Accumulated Charge registers store the total
accumulated charge delivered from the VS source to a
portable device. The bit weighting of the registers is
given in mA-hrs. The register value is reset to 00_00h
only when the RATION_RST bit is set or if the RATION_EN bit is cleared. This value will be retained when
the device transitions out of the Active state and
resumes accumulation if the device returns to the
Active state and charge rationing is still enabled.
These registers are updated every one (1) second
while the UCS2112 is in the Active power state. Every
time the value is updated, it is compared against the
target value in the Charge Rationing Threshold registers. This data is retained in the Sleep state.
REGISTER 9-12:
R-0
R-0
PORT1 TOTAL ACCUMULATED CHARGE REGISTERS (ADDRESS 16H, 17H,
18H, 19H)
R-0
R-0
R-0
R-0
R-0
R-0
TAC1<25:18>
bit 31
bit 24
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TAC1<17:10>
bit 23
bit 16
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TAC1<9:2>
bit 15
bit 8
R-0
R-0
TAC1<1:0>
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 31-6
TAC1<25:0>: Total Accumulated Charge Port 1 - Each LSB of this 26-bit value equals 0.00367 mAh.
bit 5-0
Unimplemented: Read as ‘0’'
DS20005424B-page 50
 2015 Microchip Technology Inc.
UCS2112
REGISTER 9-13:
R-0
PORT2 TOTAL ACCUMULATED CHARGE REGISTERS (ADDRESS
1AH,1BH,1CH,1DH)
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TAC2<25:18>
bit 31
bit 24
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TAC2<17:10>
bit 23
bit 16
R-0
R-0
R-0
R-0
R-0
R-0
R-0
R-0
TAC2<9:2>
bit 15
bit 8
R-0
R-0
TAC2<1:0>
U-0
U-0
U-0
U-0
U-0
U-0
—
—
—
—
—
—
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 31-6
TAC2<25:0>: Total Accumulated Charge Port 2 - Each LSB of this 26-bit value equals 0.00367 mAh.
bit 5-0
Unimplemented: Read as ‘0’'
 2015 Microchip Technology Inc.
DS20005424B-page 51
UCS2112
9.7
Charge Rationing Threshold Registers
The Charge Rationing Threshold registers set the maximum allowed charge that will be delivered to a portable
device. Every time the Total Accumulated Charge registers are updated, the value is checked against this
limit. If the value meets or exceeds this limit, the
RATION(1/2) bit is set and action taken according to
the RATION_BEH1<1:0> and RATION_BEH2<1:0>
bits.
REGISTER 9-14:
R/W-1
PORT 1 CHARGE RATIONING THRESHOLD REGISTERS (ADDRESS 1EH,1FH)
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CT1<15:8>
bit 15
R/W-1
bit 8
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CT1<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 15-0
CT1<15:0>: Charge Rationing Threshold Port 1 - Each LSB of this 16-bit value equals 3.76 mAh.
REGISTER 9-15:
R/W-1
x = Bit is unknown
PORT 2 CHARGE RATIONING THRESHOLD REGISTERS (ADDRESS 20H, 21H)
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CT2<15:8>
bit 15
R/W-1
bit 8
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
CT2<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 15-0
x = Bit is unknown
CT2: Charge Rationing Threshold Port 2 - Each LSB of this 16-bit value equals 3.76 mAh.
DS20005424B-page 52
 2015 Microchip Technology Inc.
UCS2112
REGISTER 9-16:
RATION CONFIGURATION REGISTER (ADDRESS 22H)
R/W-0
R/W-0
RTN_EN2
RTN_RST2
R/W-0
R/W-1
RTN_BEH2<1:0>
R/W-0
R/W-0
RTN_EN1
RTN_RST1
R/W-0
R/W-1
RTN_BEH1<1:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
RTN_EN2: Charge Ration Enable Port 2 - Enables Charge Rationing for Port 2.
1 = Charge Rationing enabled
0 = Charge Rationing disabled. The Total Accumulated Charge registers for port 2 will be cleared to
00_00h and current data will no longer be accumulated. If the Total Accumulated Charge registers
have already reached the Charge Rationing Threshold, the applied response will be removed as if
the charge rationing had been reset. This will also clear the RATION2 status bit (if set).
bit 6
RTN_RST2: Port 2 Ration Reset - Resets the charge rationing functionality for port 2.
1 = Total Accumulated Charge registers are reset to 00_00h. In addition, when this bit is set, the
RATION2 status bit will be cleared and, if there are no other errors or active indicators, the
ALERT#2 pin will be released.
0 = Normal operation. This bit must be cleared to enable charge rationing.
bit 5-4
RTN_BEH2<1:0>: Ration Behavior Control bits - Controls how the UCS2112 responds when the Ration
Threshold has been exceeded (as shown in Table 7-2).
00 = Report
01 = Report and Disconnect
10 = Disconnect and SLEEP
11 = Ignore
bit 3
RTN_EN1: Charge Ration Enable Port 1 - Enables Charge Rationing for Port 1.
1 = Charge Rationing enabled
0 = Charge Rationing disabled. The Total Accumulated Charge registers for port 1 will be cleared to
00_00h and current data will no longer be accumulated. If the Total Accumulated Charge registers
have already reached the Charge Rationing Threshold, the applied response will be removed as if
the charge rationing had been reset. This will also clear the RATION1 status bit (if set).
bit 2
RTN_RST1: Port 1 Ration Reset - Resets the charge rationing functionality for port 1.
1 = Total Accumulated Charge registers are reset to 00_00h. In addition, when this bit is set, the
RATION1 status bit will be cleared and, if there are no other errors or active indicators, the
ALERT#1 pin will be released.
0 = Normal operation. This bit must be cleared to enable charge rationing.
bit 1-0
RTN_BEH1<1:0>: Ration Behavior Control bits - Controls how the UCS2112 responds when the Ration
Threshold has been exceeded (as shown in Table 7-2).
00 = Report
01 = Report and Disconnect
10 = Disconnect and SLEEP
11 = Ignore
 2015 Microchip Technology Inc.
DS20005424B-page 53
UCS2112
9.8
Current Limit Behavior Registers
The Current Limit Behavior register stores the values
used by the applied current limiting mode (trip or CC).
The contents of this register are not retained in Sleep.
REGISTER 9-17:
R/W-1
PORT 1 CURRENT LIMIT BEHAVIOR REGISTER (ADDRESS 23H)
R/W-0
U-0
SEL_VBUS1_MIN<1:0>
R/W-1
—
R/W-0
R/W-1
SEL_R2_IMIN1<2:0>
R/W-1
R/W-0
Reserved
Reserved
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
SEL_VBUS1_MIN<1:0>: Define the VBUS_MIN voltage for port 1 as follows:
00 = 1.50V
01 =1.75V
10 =2.0V
11 =2.25V
bit 5
Unimplemented
bit 4-2
SEL_R2_IMIN1<2:0>: Defines the IBUS_R2MIN current.
000 =100 mA
001 =530 mA
010 =960 mA
011 =1280 mA
100 =1600 mA
101 =2130 mA
bit 1-0
Reserved: Do not change.
REGISTER 9-18:
R/W-1
PORT 2 CURRENT LIMIT BEHAVIOR REGISTER (ADDRESS 24H)
R/W-0
U-0
SEL_VBUS2_MIN<1:0>
—
R/W-1
R/W-0
R/W-1
SEL_R2_IMIN2_MIN<2:0>
R/W-1
R/W-0
Reserved
Reserved
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7-6
SEL_VBUS2_MIN<1:0>: Define the VBUS_MIN voltage for port 2 as follows:
00 = 1.50V
01 =1.75V
10 =2.0V
11 =2.25V
bit 5
Unimplemented
bit 4-2
SEL_R2_IMIN2_MIN<2:0>: Defines the IBUS_R2MIN current.
000 =100 mA
001 =530 mA
010 =960 mA
011 =1280 mA
100 =1600 mA
101 =2130 mA
bit 1-0
Reserved: Do not change.
DS20005424B-page 54
 2015 Microchip Technology Inc.
UCS2112
9.9
Product ID Register
The Product ID register stores a unique 8-bit value that
identifies the UCS device family.
REGISTER 9-19:
R-1
PRODUCT ID REGISTER (ADDRESS FDH)
R-1
R-1
R-0
R-0
R-0
R-0
R-1
PID<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-0
9.10
x = Bit is unknown
PID<7:0>: Product ID for the UCS2112.
Manufacture ID Register
The Manufacturer ID register stores a unique 8-bit
value that identifies Microchip Technology Inc.
REGISTER 9-20:
R-0
MANUFACTURER ID REGISTER (ADDRESS FEH)
R-1
R-0
R-1
R-1
R-1
R-0
R-1
MID<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-0
9.11
x = Bit is unknown
MID<7:0>: Manufacturer ID for Microchip.
Revision Register
The Revision register stores an 8-bit value that
represents the part revision.
REGISTER 9-21:
R-1
REVISION REGISTER (ADDRESS FFH)
R-0
R-0
R-0
R-0
R-0
R-0
R-1
REV<7:0>
bit 7
bit 0
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
bit 7-0
x = Bit is unknown
REV<7:0>: Part Revision.
 2015 Microchip Technology Inc.
DS20005424B-page 55
UCS2112
NOTES:
DS20005424B-page 56
 2015 Microchip Technology Inc.
UCS2112
10.0
PACKAGING INFORMATION
10.1
Package Marking Information
4x4 mm QFN, 20-lead
PIN 1
Example
PIN 1
UCS e3
2112-1
446256
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC® designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
 2015 Microchip Technology Inc.
DS20005424B-page 57
UCS2112
DS20005424B-page 58
 2015 Microchip Technology Inc.
Note: For the most current package drawings,
see the Microchip Packaging Specification at
http://www.microchip.com/packaging
UCS2112
APPENDIX A:
REVISION HISTORY
Revision B (October 2015)
• Updated Features to indicate EN/IEC 60950-1
(CB) certification.
Revision A (August 2015)
• Original release of this document.
 2015 Microchip Technology Inc.
DS20005424B-page 59
UCS2112
NOTES:
DS20005424B-page 60
 2015 Microchip Technology Inc.
UCS2112
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
[T ](1)
Device Tape and Reel
–X
–X
/XX
Version
Temperature
Range
Package
Device:
UCS2112:
Version
1
= SMBus address 57h
Temperature Range:
V
= -40°C to +105°C (Various)
Package:
G4 = Plastic Quad Flat No Lead Package - 4x4 mm Body
with 0.40 mm Contact Length, Saw Singulated,
QFN, 20-lead
 2015 Microchip Technology Inc.
Examples:
a) UCS2112-1-V/G4:
Various Temperature,
20-pin 4x4 QFN package.
b) UCS2112T-1-V/G4:
Tape and Reel,
Various Temperature,
20-pin 4x4 QFN Package.
USB Dual-Port Power Switch and Current
Monitor
Note 1:
Tape and Reel identifier only appears in the
catalog part number description. This identifier is used for ordering purposes and is not
printed on the device package. Check with
your Microchip Sales Office for package
availability with the Tape and Reel option.
DS20005424B-page 61
UCS2112
NOTES:
DS20005424B-page 62
 2015 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights unless otherwise stated.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
FlashFlex, flexPWR, JukeBlox, KEELOQ, KEELOQ logo, Kleer,
LANCheck, MediaLB, MOST, MOST logo, MPLAB,
OptoLyzer, PIC, PICSTART, PIC32 logo, RightTouch, SpyNIC,
SST, SST Logo, SuperFlash and UNI/O are registered
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
The Embedded Control Solutions Company and mTouch are
registered trademarks of Microchip Technology Incorporated
in the U.S.A.
Analog-for-the-Digital Age, BodyCom, chipKIT, chipKIT logo,
CodeGuard, dsPICDEM, dsPICDEM.net, ECAN, In-Circuit
Serial Programming, ICSP, Inter-Chip Connectivity, KleerNet,
KleerNet logo, MiWi, motorBench, MPASM, MPF, MPLAB
Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach,
Omniscient Code Generation, PICDEM, PICDEM.net, PICkit,
PICtail, RightTouch logo, REAL ICE, SQI, Serial Quad I/O,
Total Endurance, TSHARC, USBCheck, VariSense,
ViewSpan, WiperLock, Wireless DNA, and ZENA are
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
Silicon Storage Technology is a registered trademark of
Microchip Technology Inc. in other countries.
GestIC is a registered trademark of Microchip Technology
Germany II GmbH & Co. KG, a subsidiary of Microchip
Technology Inc., in other countries.
All other trademarks mentioned herein are property of their
respective companies.
© 2015, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
ISBN: 978-1-63277-902-1
QUALITY MANAGEMENT SYSTEM
CERTIFIED BY DNV
== ISO/TS 16949 ==
 2015 Microchip Technology Inc.
Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS20005424B-page 63
Worldwide Sales and Service
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://www.microchip.com/
support
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
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Tel: 86-592-2388138
Fax: 86-592-2388130
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Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
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Tel: 86-756-3210040
Fax: 86-756-3210049
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
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Tel: 91-80-3090-4444
Fax: 91-80-3090-4123
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Tel: 33-1-69-53-63-20
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Tel: 678-957-9614
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Tel: 949-462-9523
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Japan - Tokyo
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Fax: 852-2401-3431
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Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
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Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
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Fax: 886-3-5770-955
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Taiwan - Kaohsiung
Tel: 886-7-213-7828
China - Xian
Tel: 86-29-8833-7252
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Germany - Karlsruhe
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Germany - Munich
Tel: 49-89-627-144-0
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Italy - Milan
Tel: 39-0331-742611
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Italy - Venice
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Netherlands - Drunen
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Poland - Warsaw
Tel: 48-22-3325737
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07/14/15
DS20005424B-page 64
 2015 Microchip Technology Inc.