PI5USB2549

PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Features
Description
 Supports DCP Modes per USB Battery Charging
Specification 1.2
 Supports Shorted Mode per Chinese Telecommunication
Industry Standard YD/T1591-2009
 Supports non-BC1.2 Charging Modes by Automatic
Selection
The PI5USB2549 is a USB charging port controller and
current limiting power switch. PI5USB2549 provides the
electrical signatures on D+/D– to support different charging
schemes and is compatible with both popular BC1.2
compliant and non-BC1.2 compliant devices.
The PI5USB2549 65-mΩ power-distribution switch is
intended for applications where heavy capacitive loads and
short-circuits are likely to be encountered. Programmable
current threshold provides flexibility for setting current limit.
PI5USB2549 provides a /STATUS pin for plug-in detect
indication.
 Divider-1A mode
 Divider-2A mode
 Divider-2.4A mode (with MODE_SEL=’HIGH’ only)
 DCP-1.2V mode
 Integrated 65-mΩ (Typ.) High-Side MOSFET
 Programmable Current Limit up to 3A (Typ.)
 Accurate +/-7% Current Limit at 2.51A (Typ.)
 Provides /STATUS Pin for Plug-In Detection
 Operating Range:4.5V to 5.5V
 Device Package: EP-SOP8L
Applications
 Vehicle USB Power Charger
 AC-DC Wall Adapter with USB Port
 Other USB Charger
Pin Configuration
Exposed
PAD
EP-SOP8L
Typical Application Diagram
PI5USB2549
VIN
OUT
IN
2k
CIN
STATUS
VBUS
DM_IN
D-
Peripheral
Device
DP_IN
D+
Charging
GND
GND
High 2.4A
COUT
Low 2A
MODE_SEL
ILIM
18.7k (2.68A)
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1
PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Pin Description
Pin #
Name
Type
Description
1
ILIM
I
2
IN
P
3
STATUS
O
4
MODE_SEL
I
5
DP_IN
I/O
6
DM_IN
I/O
7
OUT
P
Power-switch output
8
GND
G
Ground connection
Exposed PAD
G
Ground connection.
External resistor connection used to set the current-limit threshold.
Input voltage and supply voltage; connect 0.1μF//10μF or greater ceramic capacitor
from IN to GND as close to the device as possible
Active-low open-drain output as a plug-in detect indication. It is asserted when there
is a load connected.
Logic-level input signal used to control the Divider-2.4A charging mode.
MODE_SEL=’HIGH’ enables Divider-2.4A charging mode. MODE_SEL=’LOW’
disables Divider-2.4A charging mode.
Connected to the D+ line of USB connector, provide the correct voltage with attached
portable equipment for DCP detection.
Connected to the D- line of USB connector, provide the correct voltage with attached
portable equipment for DCP detection.
* I = Input; O = Output; P = Power; G = Ground
PI5USB2549 Charging Detection Supports Table
Part Number
PI5USB2549
Non- BC1.2 Charging Mode
DCP-1.2V
Divider-1A
Divider-2A
Divider-2.4A
Plug-in
Detection
√
√
√
√
√
√
×
√
√
√
MODE_SEL
LOW
HIGH
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PT0516
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PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Maximum Ratings
All Input (except IN to OUT, and DP_IN, DM_IN).......................................................-0.3V to +6.0V
IN to OUT .................................................................................................................................-6.0V to +6.0V
DP_IN, DM_IN .................................................................................................. -0.3V to IN+0.3 or +5.7V
Input clamp current (DP_IN, DM_IN)............................................................................................ ±20mA
Continuous current in BC1.2 DCP mode (DP_IN to DM_IN) ................................................ ±50mA
Continuous output current (OUT).....................................................................................Internally limited
Continuous output sink current (/STATUS)......................................................................................25mA
Continuous output source current (ILIM)........................................................................internally limited
ESD: HBM Mode (All pins) ...................................................................................................................2kV
CDM Mode (All pins)........................................................................................................................... 500V
HBM (USB connector pins: DP_IN, DM_IN, OUT to GND).......................................................6kV
Note:
Stresses greater than 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 these or any other conditions above those
indicated in the operational sections of this specification
is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect reliability.
Recommended Operating Conditions
Symbol
Parameter
Min.
Typ.
Max.
Unit
4.5
-
5.5
V
Input Voltage, logic-level MODE_SEL input
0
-
5.5
V
VDP_IN
DP_IN data line voltage
0
-
VIN
V
VDM_IN
DM_IN data line voltage
0
-
VIN
V
Input Voltage, IN
VIN
VIH
High-level input voltage, MODE_SEL
1.8
-
-
V
VIL
Low-level input voltage, MODE_SEL
-
-
0.8
V
Continuous output current, OUT
0
-
2.5
A
Continuous output sink current, /STATUS
0
-
10
mA
Current-limit set resistor
16.9
-
750
kΩ
TA
Ambient Temperature Range
-40
-
85
ºC
TJ
Operating Virtual Junction Temperature Range
-40
-
125
ºC
IOUT
RILIM
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PT0516
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PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Electrical Characteristics
4.5V≤VIN≤5.5V; TJ=-40°C to +125°C; R/STATUS=10kΩ RILIM=20kΩ
Positive currents are into pins. Typical values are at 25°C. All voltages are with respect to GND. unless otherwise specified.
Symbol
Parameter
Test Conditions
Min
Typ.
Max
Unit
TJ = 25oC, IOUT = 2A
-
65
-
-40oC ≤ TJ ≤ 85oC, IOUT = 2A
-
65
105
-40oC ≤ TJ ≤ 125oC, IOUT = 2A
-
65
120
-
500
-
Ω
1.30
2.0
2.9
s
-
1
1.35
1.70
V
-
0.85
1.15
1.45
V
-
-
200
-
mV
-0.5
-
0.5
µA
Power Switch
RDS(on)
On Resistance(1)
mΩ
Discharge
RDCHG
OUT discharge resistance
VOUT = 4V
tDCHG
OUT discharge hold time
Time VOUT< 0.7V
MODE_SEL input
Input pin rising logic
threshold voltage
Input pin falling logic
threshold voltage
Hysteresis(2)
Input current
Pin voltage= 0V to 5.5V
(1) Pulse-testing techniques maintain junction temperature close to ambient temperature; Thermal effects must be taken into account separately
(2) These parameters are provided for reference only and do not constitute part of Pericom's published device specifications for purposes of Pericom's product
warranty
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4
PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Electrical Characteristics
4.5V≤VIN≤5.5V; TJ=-40°C to +125°C; R/STATUS=10kΩ RILIM=20kΩ
Positive currents are into pins. Typical values are at 25°C. All voltages are with respect to GND. unless otherwise specified.
Symbol
Description
Test Conditions
Min.
Typ.
Max.
Unit
205
575
2120
2340
2770
240
625
2275
2510
2970
275
680
2430
2685
3170
mA
-
1.5
-
s
-
215
270
A
ILIM Current Limit
IOS
OUT Current-limit(2)
RILIM=210kΩ
RILIM=80.6kΩ
RILIM=22.1kΩ
RILIM=20kΩ
VIN RILIM=16.9kΩ
tIOS
Response time to OUT short circuit(1)
VIN = 5.0V, R=0.1Ω, lead length=2”
Supply Current
IIN_ON
IN supply current
Undervoltage Lockout
VUVLO
IN rising UVLO threshold voltage
-
3.9
4.1
4.3
V
Hysteresis(1)
-
-
100
-
mV
/STATUS
VOL
Output low voltage
I/STATUS = 1mA
-
-
100
mV
IOFF
Off-state leakage
V/STATUS = 5.5V
-
-
1
A
170
-
20
-
Thermal Shutdown
OTSD
Thermal shutdown threshold
-
(1)
Hysteresis
-
-
°C
Note:
(1) These parameters are provided for reference only and do not constitute part of Pericom's published device specifications for purposes of Pericom's product
warranty
(2) Pulse-testing techniques maintain junction temperature close to ambient temperature; current limit value tested at 80% output voltage. Thermal effects must be
taken into account separately.
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PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Electrical Characteristics, Charging Controller
4.5V≤VIN≤5.5V; TJ=-40°C to +125°C; R/STATUS=10kΩ RILIM=20kΩ
Positive currents are into pins. Typical values are at 25°C. All voltages are with respect to GND. unless otherwise specified.
Symbol
Description
Test Conditions
Min.
Typ.
Max.
Unit
-
125
-
Ω
-
1.25
-
V
-
75
-
kΩ
DP_IN Divider-1A output voltage
1.9
2.0
2.1
V
DM_IN Divider-1A output voltage
2.57
2.7
2.84
V
DP_IN/DM_IN output impedance
7.5
10.5
16
kΩ
2.57
2.7
2.84
V
1.9
2.0
2.1
V
7.5
10.5
16
kΩ
2.57
2.7
2.84
V
7.5
10.5
16
kΩ
-
55
-
mA
-
45
-
mA
Plug-in detect set time
140
200
275
ms
Plug-in detect reset time
1.9
3
4.2
s
SHORTED MODE (BC1.2 DCP)
DP_IN/DM_IN shorting resistance
DCP-1.2V MODE
DP_IN/DM_IN output voltage
DP_IN/DM_IN output impedance
Apply 3V on DP_IN for 0.5s and
measure the D+/D- voltage within the 2s
DIVIDER-1A MODE
DIVIDER-2A MODE
DP_IN Divider-2A output voltage
DM_IN Divider-2A output voltage
IOUT= 1A
DP_IN/DM_IN output impedance
DIVIDER-2.4A MODE (with MODE_SEL=’HIGH’)
DP_IN/DM_IN output voltage
DP_IN/DM_IN output impedance
IOUT = 2A
PLUG-IN LOAD DETECT
IPLUG_IN
TPLUG_IN_
IPLUG_IN rising set current threshold
IPLUG_IN falling reset current
threshold
SET
Note:
(1) These parameters are provided for reference only and do not constitute part of Pericom's published device specifications for purposes of
Pericom's product warranty.
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6
PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Functional Description
PI5USB2549 Block Diagram
IN
OUT
UVLO+Dischager
ILIM
Current
Limit
Select
Current
Limit
Charger
Pump
OC
UVLO
GND
OTSD
Thermal
Sense
Driver
DM_IN
DP_IN
OC
DCP
Detection
Divider
Modes
Auto
Detection
STATUS
MODE_SEL
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PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Overview
The following overview references various industry standards. It is always recommended to consult the most up-to-date
standard to ensure the most recent and accurate information. Rechargeable portable equipment requires an external power
source to charge its batteries. USB ports are a convenient location for charging because of an available 5V power source.
Universally accepted standards are required to make sure host and client-side devices operate together in a system to ensure
power management requirements are met. Traditionally, host ports following the USB 2.0 specification must provide at least
500mA to downstream client-side devices. Because multiple USB devices can be attached to a single USB port through a buspowered hub, it is the responsibility of the client-side device to negotiate its power allotment from the host to ensure the total
current draw does not exceed 500mA. In general, each USB device is granted 100mA and may request more current in 100mA
unit steps up to 500mA. The host may grant or deny based on the available current. A USB 3.0 host port not only provides
higher data rate than USB 2.0 port but also raises the unit load from 100mA to 150mA. It is also required to provide a minimum
current of 900mA to downstream client-side devices.
Additionally, the success of USB has made the mini-USB connector a popular choice for wall adapter cables. This allows a
portable device to charge from both a wall adapter and USB port with only one connector. As USB charging has gained
popularity, the 500mA minimum defined by USB 2.0 or 900mA for USB 3.0 has become insufficient for many handset and
personal media players which need a higher charging rate. Wall adapters can provide much more current than 500mA/900mA.
Several new standards have been introduced defining protocol handshaking methods that allow host and client devices to
acknowledge and draw additional current beyond the 500mA/900mA minimum defined by USB 2.0/3.0 while still using a
single micro-USB input connector. The PI5USB2549 supports four of the most common USB charging schemes found in
popular hand-held media and cellular devices:




USB Battery Charging Specification BC1.2
Chinese Telecommunications Industry Standard YD/T 1591-2009
Divider-1A, Divider-2A and Divider-2.4A Mode
DCP-1.2V Mode
YD/T 1591-2009 is a subset of BC1.2 spec. supported by vast majority of devices that implement USB charging.
Divider-1A, Divider-2A, Divider-2.4A and DCP-1.2V charging schemes are supported in devices from specific yet popular
device makers.
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PT0516
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PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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DCP Auto Mode
PI5USB2549 integrates an auto-detect state machine that supports all the below DCP charging schemes. It starts in Divider-1A
scheme, however if a BC1.2 or YD/T 1591-2009 compliant device is attached, the PI5USB2549 responds by discharging OUT,
turning back on the power switch and operating in 1.2Vmode briefly and then moving to BC1.2 DCP mode. It then stays in that
mode until the device is done charging or removed, in which case it goes back to Divider-1A scheme. When a Divider-1A
compliant device is attached the PI5USB2549 will stay in Divider-1A state.
Also, the PI5USB2549 will automatically switch between the Divider-1A and Divider-2A (or Divider-2.4A) schemes based on
charging current drawn by the connected device. Initially the device will set the DP_IN/DM_IN to Divider-1A scheme. If
charging current of the device >900mA is measured by the PI5USB2549, it switches to Divider-2A scheme and test to see if the
peripheral device will still charge at a high current. With MODE_SEL=’HIGH’, if charging current of the device >1.8A is
measured by PI5USB2549 or PI5USB2549, it will switches to Divider-2.4A charging mode. If it does then it stays in Divider2A or Divider-2.4A charging scheme otherwise it will revert to Divider-1A scheme.
PI5USB2549
DDCP Auto
BC1.2 DCP
/DCP-1.2V
D+
Divider-1A
/2A /2.4A
Figure 1, DCP_Auto Mode
DCP BC1.2 and YD/T 1591-2009
Both standards define that the D+ and D- data lines should be shorted together with a maximum series impedance of 200Ω.
This is shown as Figure 1.
VBUS
PI5USB2549
200Ω
2.0V
Auto
Detect
D-
USB
Connector
1.2V
2.7V
D+
GND
Figure 2, DCP mode
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PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Divider-1A, Divider-2A and Divider-2.4A Charging Scheme
There is two charging mode supported by PI5USB2549 with MODE_SEL pin LOW or HIGH. PI5USB2549 supports to flag
Divider-1A/Divider-2A/Divider-2.4A charging scheme as MODE_SEL pin pulls to IN (HIGH), and if MODE_SEL pin pulls to
GND (LOW), the device supports to flag Divider-1A/Divider-2A charging scheme. In Divider-1A charging scheme the device
applies 2.0V and 2.7V to D+ and D- data line respectively. This is reversed in Divider-2A mode. Divider-2.4A charging
scheme on PI5USB2549 is applying 2.7V on both D+ and D-. The Divider-1A, Divider-2A and Divider-2.4A scheme are as
shown below.
VBUS
PI5USB2549
2.7V
D-
Auto
Detect
USB
Connector
1.2V
2.0V
D+
GND
Figure 3a, Divider-1A Charging Scheme (with MODE_SEL=“LOW”)
VBUS
PI5USB2549
2.0V
D-
Auto
Detect
USB
Connector
1.2V
2.7V
D+
GND
Figure 3b, Divider-2A Charging Scheme (with MODE_SEL=“LOW”)
PI5USB2549
VBUS
2.7V
D-
Auto
Detect
USB
Connector
1.2V
2.7V
D+
GND
Figure 3c, Divider-2.4A Charging Scheme (with MODE_SEL=“HIGH”)
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PT0516
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PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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DCP-1.2V Charging Scheme
DCP-1.2V charging scheme is used by some handheld devices to enable fast charging at 2.0A. PI5USB2549 supports this
scheme in the DCP-Auto mode before the device enters BC1.2 shorted mode. To simulate this charging scheme D+/D- lines are
shorted and pulled-up to 1.2V for fixed duration then device moves to DCP shorted mode as defined in BC1.2 spec. This is
shown as Figure 3.
VBUS
PI5USB2549
2.0V
D-
Auto
Detect
USB
Connector
1.2V
2.7V
D+
GND
Figure 4, DCP-1.2V Charging Scheme
Output Discharge
To allow a charging port to renegotiate current with a portable device, PI5USB2549 uses the OUT discharge function. It
proceeds by turning off the power switch while discharging OUT, then turning back on the power switch to reassert the OUT
voltage.
Over-Current Protection
When an over-current condition is detected, the device maintains a constant output current and reduces the output voltage
accordingly. Two possible overload conditions can occur. In the first condition, the output has been shorted before the device is
enabled or before VIN has been applied. The PI5USB2549 senses the short and immediately switches into a constant-current
output. In the second condition, a short or an overload occurs while the device is enabled. At the instant the overload occurs,
high currents may flow for nominally one to two microseconds before the current-limit circuit can react. The device operates in
constant-current mode after the current-limit circuit has responded. Complete shutdown occurs only if the fault is presented
long enough to activate thermal limiting. The device will remain off until the junction temperature cools approximately 20°C
and will then re-start. The device will continue to cycle on/off until the over-current condition is removed.
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8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Current-Limit Setting
The PI5USB2549 has an independent current limit setting that is programmed externally with a resistor. The ILIM setting is
programmed with RILIM connected between ILIM and GND.
The following equation programs the typical current limit:
IOS_TYP (mA)=50250/RLIM (kΩ)
Many applications require that the current limit meet specific tolerance limits. When designing to these tolerance limits, both
the tolerance of the PI5USB2549 current limit and the tolerance of the external programming resistor must be taken into
account. The following equations approximate the PI5USB2549 minimum / maximum current limits to within a few mA and
are appropriate for design purposes. These equations assume an ideal – no variation - external programming resistor. To take
resistor tolerance into account, first determine the minimum /maximum resistor values based on its tolerance specifications and
use these values in the equations. Because of the inverse relation between the current limit and the programming resistor, use
the maximum resistor value in the IOS_MIN equation and the minimum resistor value in the IOS_MAX equation.
IOS_MIN (mA)=45271/(RLIM (kΩ))0.98437-30
IOS_MAX (mA) =55325/ (RLIM (kΩ)) 1.0139+30
The traces routing the RILIMI resistor should be a sufficiently low resistance as to not affect the current-limit accuracy. The
ground connection for the RILIM resistor is also very important. The resistors need to reference back to the PI5USB2549 GND
pin. Follow normal board layout practices to ensure that current flow from other parts of the board does not impact the ground
potential between the resistors and the PI5USB2549 GND pin.
Undervoltage Lockout (UVLO)
The undervoltage lockout (UVLO) circuit disables the power switch until the input voltage reaches the UVLO turn on threshold.
Built-in hysteresis prevents unwanted oscillations on the output due to input voltage drop from large current surges.
Thermal Sense
The PI5USB2549 protects itself with thermal sensing circuit that monitor the operating temperature of the power distribution
switch and disables operation if the temperature exceeds recommended operating conditions. The device operates in constantcurrent mode during an over-current condition, which increases the voltage drop across power switch. The power dissipation in
the package is proportional to the voltage drop across the power switch, so the junction temperature rises during an over-current
condition. The thermal sensor turns off the power switch when the die temperature exceeds 135°C regardless of whether the
power switch is in current limit. Hysteresis is built into thermal sensor, and the switch turns on after the device has cooled by
approximately 20°C. The switch continues to cycle off and on until the fault is removed.
Application Information
Input and Output Capacitance
Input and output capacitance improves the performance of the device; the actual capacitance should be optimized for the particular
application. For all applications, a 0.1uF or greater ceramic bypass capacitor between IN and GND is recommended as close to the
device as possible for local noise decoupling. This precaution reduces ringing on the input due to power-supply transients.
Additional input capacitance 10uF or greater may be needed on the input to reduce voltage overshoot from exceeding the absolutemaximum voltage of the device during heavy transient conditions or output shorting. Normally suggested the distance between IC
and DC supply is less than 15cm.
Output capacitance also needs to be close to IC as possible. When large transient currents are expected on the output, placing a
high-value low ESR electrolytic capacitor 100uF or greater on the output pin is recommended.
All trademarks are property of their respective owners 2014-08-0001
www.pericom.com
12
PT0516
8/27/14
PI5USB2549
USB Charging Port Controller and Load Detection Power Switch
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Mechanical Information
EP-SOP8L
Ordering Information
Part No.
PI5USB2549WAE
Package Code
WA
Package
Lead free and Green 8-pin EP-SOP
Note:

E = Pb-free and Green

Adding X Suffix= Tape/Reel
Pericom Semiconductor Corporation  1-800-435-2336 www.pericom.com
Pericom reserves the right to make changes to its products or specifications at any time, without notice, in order to improve design or performance and to supply
the best possible product. Pericom does not assume any responsibility for use of any circuitry described other than the circuitry embodied in Pericom product. The
company makes no representations that circuitry described herein is free from patent infringement or other rights, of Pericom.
All trademarks are property of their respective owners 2014-08-0001
www.pericom.com
13
PT0516
8/27/14