NCP1850 D

NCP1850
Fully Integrated Li-Ion
Switching Battery Charger
with Power Path
Management and USB
On-The-Go Support
The NCP1850 is a fully programmable single cell Lithium−ion
switching battery charger optimized for charging from a USB
compliant input supply and AC adaptor power source. The device
integrates a synchronous PWM controller, power MOSFETs, and the
entire charge cycle monitoring including safety features under
software supervision. An optional battery FET can be placed between
the system and the battery in order to isolate and supply the system.
The NCP1850 junction temperature and battery temperature are
monitored during charge cycle, and both current and voltage can be
modified accordingly through I2C setting. The charger activity and
status are reported through a dedicated pin to the system. The input pin
is protected against overvoltages.
The NCP1850 also provides USB OTG support by boosting the
battery voltage as well as providing overvoltage protected power
supply for USB transceiver.
MARKING
DIAGRAM
WLCSP25
CASE 567FZ
1850
A
Y
WW
G
1850
AYWW
G
= Specific Device Code
= Assembly Location
= Year
= Work Week
= Pb−Free Package
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 29 of this data sheet.
Features
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1.5 A Buck Converter with Integrated Pass Devices
Input Current Limiting to Comply to USB Standard
Automatic Charge Current for AC Adaptor Charging
High Accuracy Voltage and Current Regulation
Input Overvoltage Protection up to +28 V
Factory Mode
250 mA Boosted Supply for USB OTG Peripherals
Reverse Leakage Protection Prevents Battery Discharge
Protected USB Transceiver Supply Switch
Dynamic Power Path with Optional Battery FET
Battery Temperature Sensing for Safe Operation
Silicon Temperature Supervision for Optimized Charge Cycle
Safety Timers
Flag Output for Charge Status and Interrupts
INTB Output for Interrupts
I2C Control Bus up to 3.4 MHz
Small Footprint 2.2 x 2.55 mm CSP Package
These Devices are Pb−Free and are RoHS Compliant
Applications
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Smart Phone
Handheld Devices
Tablets
PDAs
© Semiconductor Components Industries, LLC, 2013
May, 2013 − Rev. 1
1
Publication Order Number:
NCP1850/D
NCP1850
PIN CONNECTIONS
1
2
3
4
5
A
IN
IN
SPM
SDA
SCL
B
CAP
CAP
OTG
ILIMB
FLAG
C
SW
SW
AGND
ILIM
NTC
D
PGND
PGND
SENSP
SENSN
FET
E
CBOOT
TRANS
CORE
WEAK
BAT
(Top View)
Figure 1. Package Outline CSP
Table 1. PIN FUNCTION DESCRIPTION
Pin
Name
Type
A1
IN
POWER
Description
Battery Charger Input. These two pins must be decoupled by at least 1 mF capacitor and
connected together.
A2
IN
POWER
A3
SPM
DIGITAL INPUT
System Power Monitor input.
A4
SDA
DIGITAL
BIDIRECTIONAL
I2C data line
A5
SCL
DIGITAL INPUT
I2C clock line
B1
CAP
POWER
B2
CAP
POWER
B3
OTG
DIGITAL INPUT
B4
ILIMB
OPEN DRAIN
OUTPUT
Connect to interrupt pin of the system, active low
B5
FLAG
OPEN DRAIN
OUTPUT
Charging state active low. This is an open drain pin that can either drive a status LED or
connect to interrupt pin of the system.
C1
SW
ANALOG OUTPUT
C2
SW
ANALOG OUTPUT
C3
AGND
ANALOG GROUND
C4
ILIM
DIGITAL INPUT
Input current limiter level selection (can be defeated by I2C).
C5
NTC
ANALOG INPUT
Input for the battery NTC (10 KW / B = 3900) or (4.7 KW / B = 3900) If not used, this pin
must be tied to GND to configure the NCP1850 and warn that NTC is not used.
D1
PGND
POWER GND
D2
PGND
POWER GND
D3
SENSP
ANALOG INPUT
CAP pin is the intermediate power supply input for all internal circuitry. Bypass with at
least 4.7 mF capacitor. Must be tied together.
Enables OTG boost mode.
OTG = 0, the boost is powered OFF
OTG = 1 turns boost converter ON
Connection from power MOSFET to the Inductor. These pins must be connected together.
Analog ground / reference. This pin should be connected to the ground plane and must be
connected together.
Power ground. These pins should be connected to the ground plane and must be
connected together.
Current sense input. This pin is the positive current sense input. It should be connected to
the RSENSE resistor positive terminal.
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NCP1850
Table 1. PIN FUNCTION DESCRIPTION
Pin
Name
Type
Description
D4
SENSN
ANALOG INPUT
Current sense input. This pin is the negative current sense input. It should be connected to
the RSENSE resistor negative terminal. This pin is also voltage sense input of the voltage
regulation loop when the FET is present and open.
D5
FET
ANALOG OUTPUT
E1
CBOOT
ANALOG IN/OUT
E2
TRANS
ANALOG OUTPUT
Output supply to USB transceiver. This pin can source a maximum of 30 mA to the
external USB PHY or any other IC that needs +5 V USB. This pin is Overvoltage protected
and will never be higher than 5.5 V. This pin should be bypassed by a 100 nF ceramic
capacitor.
E3
CORE
ANALOG OUTPUT
5 V reference voltage of the IC. This pin should be bypassed by a 2.2 mF capacitor. No
load must be connected to this pin.
E4
WEAK
ANALOG OUTPUT
Weak battery charging current source input.
E5
BAT
ANALOG INPUT
Battery FET driver output. When not used, this pin must be directly tied to ground.
Floating Bootstrap connection. A 10 nF capacitor must be connected between CBOOT
and SW.
Battery connection
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NCP1850
Table 2. MAXIMUM RATINGS
Rating
Symbol
Value
Unit
VIN
−0.3 to +28
V
CAP (Note 1)
VCAP
−0.3 to +28
V
Power balls: SW, CBOOT (Note 1)
VPWR
−0.3 to +24
V
IN pin with respect to VCAP
VIN_CAP
−0.3 to +7.0
V
SW with respect to SW
VSW_CAP
−0.3 to +7.0
V
VCTRL
−0.3 to +7.0
V
Digital Input: SCL, SDA, SPM, OTG, ILIM (Note 1)
Input Voltage
Input Current
VDG
IDG
−0.3 to +7.0 V
20
V
mA
Human Body Model (HBM) ESD Rating are (Note 2)
ESD HBM
2000
V
Machine Model (MM) ESD Rating are (Note 2)
ESD MM
200
V
IN (Note 1)
Sense/Control balls: SENSP, SENSN, VBAT, FET, TRANS, CORE, NTC, FLAG,
INTB and WEAK. (Note 1)
Latch up Current (Note 3):
All Digital pins( VDG), FET
All others pins.
ILU
Storage Temperature Range
Maximum Junction Temperature (Note 4)
Moisture Sensitivity (Note 5)
mA
10
±100
TSTG
−65 to + 150
°C
TJ
−40 to + TSD
°C
MSL
Level 1
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
1. With respect to PGND. According to JEDEC standard JESD22−A108
2. This device series contains ESD protection and passes the following tests:
Human Body Model (HBM) ±2.0 kV per JEDEC standard: JESD22−A114 for all pins.
Machine Model (MM) ±200 V per JEDEC standard: JESD22−A115 for all pins.
3. Latch up Current Maximum Rating: ±100 mA or per ±10 mA JEDEC standard: JESD78 class II.
4. A thermal shutdown protection avoids irreversible damage on the device due to power dissipation. See Electrical Characteristics.
5. Moisture Sensitivity Level (MSL): 1 per IPC/JEDEC standard: J−STD−020.
Table 3. OPERATING CONDITIONS
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VIN
Operational Power Supply (Note 6)
3
VINOV
V
VDG
Digital input voltage level
0
5.5
V
+85
°C
10
mA
TA
ISINK
CIN
Ambient Temperature Range
−40
25
FLAG sink current
1
mF
Decoupling Switcher capacitor
4.7
mF
Decoupling core supply capacitor
2.2
mF
Decoupling system capacitor
10
mF
Switcher Inductor
2.2
mH
RSNS
Current sense resistor
68
mW
RqJA
Thermal Resistance Junction−to−Air
CCAP
CCORE
COUT
LX
TJ
Decoupling input capacitor
(Notes 7 and 8)
Junction Temperature Range
60
−40
25
°C/W
+125
6. OVLO is selectable per metal option (see ELECTRICAL CHARACTERISTICS table).
7. A thermal shutdown protection avoids irreversible damage on the device due to power dissipation. See Electrical Characteristics.
8. The RqJA is dependent on the PCB heat dissipation. Board used to drive this data was a 2s2p JEDEC PCB standard.
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°C
NCP1850
Table 4. ELECTRICAL CHARACTERISTICS
Min & Max Limits apply for TA between −40°C to +85°C and TJ up to + 125°C for VIN between 3.6 V to 7 V (Unless otherwise noted).
Typical values are referenced to TA = + 25°C and VIN = 5 V (Unless otherwise noted).
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Valid input detection threshold
VIN rising
3.55
3.6
3.65
V
VIN falling
2.95
3.0
3.05
V
VIN falling
4.3
4.4
4.5
V
Hysteresis
50
100
150
mV
VIN rising
5.55
5.65
5.75
V
INPUT VOLTAGE
VINDET
VBUSUV
USB under voltage detection
VBUSOV
USB over voltage detection
VINOV
VINOV
Valid input high threshold
Hysteresis
25
75
125
mV
VIN rising
7.1
7.2
7.3
V
Hysteresis
200
300
400
mV
IINLIM set to
100 mA
70
85
100
mA
IINLIM set to
500 mA
425
460
500
mA
IINLIM set to
900 mA
800
850
900
mA
IINLIM set to
1500 mA
1.4
1.45
1.5
A
INPUT CURRENT LIMITING
IINLIM
Input current limit
VIN = 5 V
INPUT SUPPLY CURRENT
IQ_SW
VBUS supply current
IOFF
No load, Charger active state
15
mA
Charger not active, NTC disable
500
mA
CHARGER DETECTION
VCHGDET
Charger detection threshold
voltage
VIN – VSENSN, VIN rising
50
200
VIN – VSENSN, VIN falling
10
50
mV
REVERVE BLOCKING CURRENT
ILEAK
VBAT leakage current
Battery leakage, VBAT = 4.2 V VIN = 0 V,
SDA = SCL = 0 V
RRBFET
Input RBFET On resistance
(Q1)
Charger active state, Measured between
IN and CAP,VIN = 5 V
5
7
mA
45
90
mW
4.5
V
−0.5
0.5
%
−1
1
−
BATTERY AND SYSTEM VOLTAGE REGULATION
VCHG
Output voltage range
Programmable by I2C
3.3
Default value
Voltage regulation accuracy
Constant voltage mode, TA = 25°C
3.6
I2C Programmable granularity
25
mV
BATTERY VOLTAGE THRESHOLD
VSAFE
Safe charge threshold voltage
VBAT rising
2.1
2.15
2.2
V
VPRE
Conditioning charge threshold
voltage
VFET = 3.1 V and 3.2 V
2.95
3
3.05
V
VFET = 3.3 V, 3.4 V, 3.5 V and 3.6 V
3.15
3.2
3.25
9. Minimum transition time from states to states.
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NCP1850
Table 4. ELECTRICAL CHARACTERISTICS
Min & Max Limits apply for TA between −40°C to +85°C and TJ up to + 125°C for VIN between 3.6 V to 7 V (Unless otherwise noted).
Typical values are referenced to TA = + 25°C and VIN = 5 V (Unless otherwise noted).
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
3.15
3.2
3.25
V
2
%
BATTERY VOLTAGE THRESHOLD
VFET
End of weak charge threshold
voltage
VBAT rising
Voltage range
Default value
Accuracy
3.4
−2
I2C
Programmable
granularity
100
mV
VRECHG
Recharge threshold voltage
Relative to VCHG setting register
97
%
VBUCKOV
Overvoltage threshold voltage
VBAT rising, relative to VCHG setting register,
measured on SENSN or SENSP, QBAT close or no
QBAT
115
%
QBAT open.
5
V
CHARGE CURRENT REGULATION
Charge current range
ICHG
Programmable by I2C
400
Default value
950
Charge current accuracy
I2C
IPRE
−50
Programmable granularity
Pre−charge current
1000
1600
mA
1050
mA
50
mA
100
VBAT < VPRE
405
450
mA
495
mA
ISAFE
Safe charge current
VBAT < VSAFE
8
10
12
mA
IWEAK
Weak battery charge current
BATFET present,
VSAFE < VBAT < VFET
80
100
120
mA
275
mA
CHARGE TERMINATION
IEOC
Charge current termination
VBAT ≥ VRECHG
Current range
100
Default value
Accuracy, IEOC
< 200 mA
150
−25
I2C
Programmable
granularity
25
25
FLAG
VFOL
FLAG output low voltage
IFLAG = 10 mA
0.5
V
IFLEAK
Off−state leakage
VFLAG = 5 V
1
mA
DIGITAL INPUT (VDG)
VIH
High−level input voltage
1.2
VIL
Low−level input voltage
RDG
Pull down resistor
IDLEAKK
Input current
VDG = 0 V
−0.5
VSYSUV
CAP pin supply voltage
I2C registers available
2.5
VI2CINT*
High level at SCL/SCA line
VI2CIL
SCL, SDA low input voltage
VI2CIH
SCL, SDA high input voltage
V
0.4
500
V
kW
0.5
mA
I2C
1.7
0.8 *
VI2CINT
9. Minimum transition time from states to states.
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V
5
V
0.4
V
V
NCP1850
Table 4. ELECTRICAL CHARACTERISTICS
Min & Max Limits apply for TA between −40°C to +85°C and TJ up to + 125°C for VIN between 3.6 V to 7 V (Unless otherwise noted).
Typical values are referenced to TA = + 25°C and VIN = 5 V (Unless otherwise noted).
Symbol
Parameter
Conditions
VI2COL
SCL, SDA low output voltage
ISINK = 3 mA
FSCL
I2C clock frequency
Min
Typ
Max
Unit
I2C
0.3
V
3400
kHz
150
°C
JUNCTION THERMAL MANAGEMENT
TSD
Thermal shutdown
Rising
125
140
Falling
115
°C
−7
°C
TH2
Hot temp threshold 2
Relative to TSD
TH1
Hot temp threshold 1
Relative to TSD
−11
°C
TWARN
Thermal warning
Relative to TSD
−15
°C
BATTERY THERMAL MANAGEMENT
VNTCRMV
VCOLD
VHOT
VNTCDIS
VREG
RNTCPU
Battery removed threshold
voltage
Battery cold temperature corresponding voltage threshold
VNTC Rising
2.3
2.325
2.4
BATCOLD[1:0]:00
1.775
1.8
1.825
BATCOLD[1:0]:01
1.7
1.725
1.75
BATCOLD[1:0]:10
1.625
1.65
1.675
BATCOLD[1:0]:11
1.55
1.575
1.6
V
BATHOT[1:0]:00
800
825
850
BATHOT[1:0]:01
725
750
775
BATHOT[1:0]:10
650
675
700
BATHOT[1:0]:11
575
600
625
VNTC Falling
50
75
100
mV
Internal voltage reference
2.35
2.4
2.45
V
Internal resistor pull up
9.8
10
10.2
kW
Switching Frequency
−
3
−
MHz
Switching Frequency
Accuracy
−10
+10
%
Battery hot temperature corresponding voltage threshold
NTC disable corresponding
voltage threshold
mV
BUCK CONVERTER
FSWCHG
TDTYC
Max Duty Cycle
Average
99.5
%
IPKMAX
Maximum peak inductor
current
1.9
A
RONLS
Low side Buck MOSFET
RDSON (Q3)
Measured between PGND and SW, VIN = 5 V
−
170
350
mW
RONHS
High side Buck MOSFET
RDSON(Q2)
Measured between CAP and SW, VIN = 5 V
−
140
285
mW
5
5.5
V
PROTECTED TRANSCEIVER SUPPLY
VTRANS
Voltage on TRANS pin
ITRMAX
TRANS current capability
VIN ≥ 5 V
30
mA
TIMING
TWD
Watchdog timer
32
s
TUSB
USB timer
2048
s
9. Minimum transition time from states to states.
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NCP1850
Table 4. ELECTRICAL CHARACTERISTICS
Min & Max Limits apply for TA between −40°C to +85°C and TJ up to + 125°C for VIN between 3.6 V to 7 V (Unless otherwise noted).
Typical values are referenced to TA = + 25°C and VIN = 5 V (Unless otherwise noted).
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
TIMING
TCHG1
Charge timer
TCHG2
TWU
Safe−charge or pre−charge or weak−safe or
weak− charge state.
3
h
Full−charge state
2
h
Wake−up timer
64
s
VBAT rising
15
ms
VBAT falling
127
ms
TVRCHR
Deglitch time for end of
charge voltage detection
TINDET
Deglitch time for input voltage
detection
VIN rising
15
ms
TDGS1
Deglitch time for signal
crossing IEOC, VPRE, VSAFE,
VCHGDET, VINEXT thresholds.
Rising and falling edge
15
ms
TDGS2
Deglitch time for signal
crossing VFET, VBUSUV,
VBUSOV thresholds.
Rising and falling edge
1
ms
From Weak Charge to Full Charge State
32
s
From Wait to Charger active state
128
ms
TSTWC
TSTW
Charger state timer
(Note 9)
From Weak Charge to Full
Charge State, triggered on
TST_SET level transition.
TST
TST_SET = 0
32
TST_SET = 1
16
ms
16
ms
All others states
24
s
BOOST CONVERTER AND OTG MODE
VIBSTL
Boost minimum input
operating range
VIBSTH
Boost maximum input
operating range
3.1
3.2
3.3
Boost running
2.9
3
3.1
4.4
4.5
4.6
5.1
5.15
V
3
%
VOBST
Boost Output Voltage
DC value measured on CAP pin, no load
5.00
VOBSTAC
Boost Output Voltage
accuracy
Measured on CAP pin Including line and load
regulation
−3
IBSTMX
Output current capability
FSWBST
Switching Frequency
250
Maximum peak inductor
current
VOBSTOL
Boost overload
−10
MHz
10
1.9
Boost running, voltage on IN pin
4.3
V
mA
1.5
Switching Frequency
Accuracy
IBPKM
V
Boost start−up
4.4
%
A
4.5
V
TOBSTOL
Maximum capacitance on IN pin during start−up
10
mF
ROBSTOL
Maximum load on IN pin during start−up
50
W
VOBSTOV
Overvoltage protection
VIN rising
5.55
5.65
5.75
V
Hysteresis
25
75
125
mV
9. Minimum transition time from states to states.
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NCP1850
BLOCK DIAGRAM
CCAP
4.7mF
CAP
VCAP
IN
VBUS
D+
D−
GND
CBOOT
CIN
Q1
Charge
Pump
1mF
VCORE
CBOOT
Drv
Q2
10nF
VCAP
IINREG
5V
reference
VREG
VCORE
CORE
Current,
Voltage,
and Clock
Reference
ICHG
SW
PWM generator
CCORE
Drv
VTJ
VCHG
Q3
LX
VCORE
2.2mF
2.2mF
Drv
TRANS
CTRS
PGND
+ IEOC
VTJ
+
0.1mF
+
TWARN −
RSNS
+
Amp
−
68mW
SENSN
+
WEAK
− V
RECHG
+
+
ICHG
− V
BATOV
TH2 −
TH1 −
SENSP
+
TSD −
USB PHY
VBAT
− I
BAT
I2C &
DIGITAL
CONTROLER
+
− V
FET
QBAT*
+
CSYS
− VPRE
OTG
10mF
+
−
ILIM
VSAFE
BAT
INTB
DRV
+
VIN
+
VINDET −
+
VBUSUV −
+
VBUSOV
AGND
VINOV
VBAT
−
VRMOVED
+
−
BATFET detection
& Drive
VREG
RNTCPU
+ VHOT
−
−
+
NTC
VCOLD
−
+
FET
SPM
VNTCDIS
−
+
−
DRV
FLAG
SCL
VCHGDET +
SDA
* Optional
Figure 2. Block Diagram
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+
NCP1850
TYPICAL APPLICATION CIRCUITS
LX 2.2mH
VBUS
D+
D−
ID
GND
CIN
IN
CBOOT
CAP
COUT
10mF
10nF
SENSP
WEAK
FET
CORE
2.2mF
QBAT(*)
BAT
NTC
CTRANS
SYSTEM
SENSN
4.7mF
CCORE
RSNS 68mW
CBOOT
NCP1850
1mF
CCAP
SW
+
TRANS
100nF
FLAG
SCL
AGND
SDA
PGND
SPM
ILIM
INTB
OTG
Figure 3. USB Charger with Battery External MOSFET
LX
VBUS
D+
D−
ID
GND
CIN
CBOOT
CAP
4.7mF
CCORE
2.2mF
CBOOT
NCP1850
1mF
CCAP
SW
IN
SYSTEM
10nF
SENSP
RSNS
SENSN
68mW
WEAK
CORE
CSYS
FET
+
2.2mF
10mF
BAT
NTC
CTRANS
TRANS
100nF
FLAG
SCL
AGND
PGND
SDA
SPM
ILIM
INTB
OTG
Figure 4. USB Charger without Battery External MOSFET
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NCP1850
CHARGE MODE OPERATION
The NCP1850 is fully programmable through I2C
interface (see Registers Map section for more details). All
registers can be programmed by the system controller at any
time during the charge process. The charge current (ICHG),
charge voltage (VCHG), and input current (IINLIM) are
controlled by a dynamic voltage and current scaling for
disturbance reduction. Is typically 10 ms for each step.
NCP1850 also provides USB OTG support by boosting
the battery voltage as well as an over voltage protected
power supply for USB transceiver.
Overview
The NCP1850 is a fully programmable single cell
Lithium−ion switching battery charger optimized for
charging from a USB compliant input supply. The device
integrates a synchronous PWM controller; power
MOSFETs, and monitoring the entire charge cycle including
safety features under software supervision. An optional
battery FET can be placed between the system and the
battery in order to isolate and supply the system in case of
weak battery. The NCP1850 junction temperature and
battery temperature are monitored during charge cycle and
current and voltage can be modified accordingly through
I2C setting. The charger activity and status are reported
through a dedicated pin to the system. The input pin is
protected against overvoltages.
Charge Profile
In case of application without QFET (see Figure 4), the
NCP1850 provides four main charging phases as described
below. Unexpected behavior or limitations that can modify
the charge sequence are described further (see Charging
Process section).
VBAT
IBAT
VCHG
VRECHG
ICHG
IPRE
VPRE
IEOC
ISAFE
VSAFE
Safe
Charge
Pre
Charge
Constant
Current
Constant
Voltage
End of
Charge
Figure 5. Typical Charging Profile of NCP1850
current. The battery stays in preconditioning until the VBAT
voltage is lower than VPRE threshold.
Constant Current (full charge):
In the constant current phase (full charge state), the
DC−DC convertor is enabled and an ICHG current is
delivered to the load. As battery voltage could be sufficient,
the system may be awake and sink an amount of current. In
this case the charger output load is composed of the battery
and the system. Thus ICHG current delivered by the
NCP1850 is shared between the battery and the system:
ICHG = ISYS + IBAT.
Safe Charge:
With a disconnected battery or completely empty battery,
the charge process is in safe charge state, the charge current
is set to ISAFE in order to charge up the system’s capacitors
or the battery. When the battery voltage reaches VSAFE
threshold, the battery enters in pre−conditioning.
Pre Conditioning (pre−charge):
In preconditioning (pre charge state), the DC−DC
convertor is enabled and an IPRE current is delivered to the
battery. This current is much lower than the full charge
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NCP1850
System
awake
VBAT
VCHG
VRECHG
ICHG
IBAT
VBAT
IBAT
IPRE
ISYS
VPRE
IEOC
ISAFE
VSAFE
Safe
Charge
Pre
Charge
Constant
Current
Constant
Voltage
End of
Charge
Figure 6. Typical Charging Profile of NCP1850 with System Awake
ICHG current is programmable using I2C interface
(register IBAT_SET − bits ICHG[3:0]).
measured input current and output voltage are below the
programmed limit and asking for more power. But in the
same time, the measured output current is at the
programmed limit and thus regulates the DC−DC converter.
In order to prevent battery discharge and overvoltage
protection, Q1(reverse voltage protection) and Q2 (high side
N−MOSFET of the DC−DC converter) are mounted in a
back−to−back common drain structure while Q3 is the low
side N MOSFET of the DC−DC converter. Q2 gate driver
circuitry required an external bootstrap capacitor connected
between CBOOT pin and SW pin.
An internal current sense monitors and limits the
maximum allowable current in the inductor to IPEAK value.
Constant Voltage (full charge):
The constant voltage phase is also a part of the full charge
state. When the battery voltage is close to its maximum
(VCHG), the charge circuit will transition from a constant
current to a constant voltage mode where the charge current
will slowly decrease (taper off). The battery is now voltage
controlled. VCHG voltage is programmable using I2C
interface (register VBAT_SET− bits CTRL_VBAT[5:0]).
End of Charge:
The charge is completed (end of charge state) when the
battery is above the VRECHG threshold and the charge
current below the IEOC level. The battery is considered fully
charged and the battery charge is halted. Charging is
resumed in the constant current phase when the battery
voltage drops below the VRECHG threshold. IEOC current is
programmable using I2C interface (register IBAT_SET−
bits IEOC[2:0]).
The charge cycle can also be halted manually through I2C
(register CRTL2 bit CHG_HALT=1).
Charger Detection, Start−up Sequence and System Off
The start−up sequence begins upon an adaptor valid
voltage plug in detection: VIN > VINDET and VIN − VBAT >
VCHGDET (off state).
Then, the internal circuitry is powered up and the presence
of NTC and BATFET are reported (register STATUS – bit
BATFET and NTC). When the power−up sequence is done,
the charge cycle is automatically launched. At any time and
any state, the user can holds the charge process and transit
to fault state by setting CHG_EN to ‘0’ (register CTRL1) in
the I2C register. Furthermore, during fault state, NTC block
can be disabled for power saving (bit NTC_EN register
CTRL1)
The I2C registers are accessible without valid voltage on
VIN if VCAP > VSYSUV (i.e. if VBAT is higher than VSYSUV
+ voltage drop across Q2 body diode).
At any time, the user can reset all register stack (register
CTRL1 – bit REG_RST).
Power Stage Control
NCP1850 provides a fully−integrated 3 MHz step−down
DC−DC converter for high efficiency. For an optimized
charge control, three feedback signals controls the PWM
duty cycle. These three loops are: maximum input current
(IINLIM), maximum charge current (ICHG) and, maximum
charge voltage (VCHG). The switcher is regulated by the first
loop that reaches its corresponding threshold. Typically
during charge current phase (VPRE < VBAT < VRECHG), the
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NCP1850
Weak Battery Support
Weak Wait
An optional battery FET (QBAT) can be placed between
the application and the battery. In this way, the battery can
be isolated from the application and so−called weak battery
operation is supported.
Typically, when the battery is fully discharged, also
referred to as weak battery, its voltage is not sufficient to
supply the application. When applying a charger, the battery
first has to be pre−charged to a certain level before operation.
During this time; the application is supplied by the DC−DC
converter while integrated current sources will pre−charge
the battery to the sufficient level before reconnecting.
The pin FET can drive a PMOS switch (QBAT) connected
between BAT and WEAK pin. It is controlled by the charger
state machine (Charging process section). The basic
behavior of the FET pin is that it is always low. Thus the
PMOS is conducting, except when the battery is too much
discharged at the time a charger is inserted under the
condition where the application is not powered on. The FET
pin is always low for BAT above the VFET threshold. Some
exceptions exist which are described in the Charging
Process and Power Path Management section. The VFET
threshold is programmable (register MISC_SET – bit
CTRL_VFET).
Weak wait state is entered from wait state (see Charging
process section) in case of BATFET present, battery voltage
lower than VFET and host system in shutdown mode (SPM
= 0). The DCDC converter from VIN to SW is enabled and
set to VCHG while the battery FET QBAT is opened. The
system is now powered by the DC−DC. The internal current
source to the battery is disabled. In weak wait state, the state
machine verifies if the battery temperature is OK thanks to
the NTC sensor. If NTC OK or if NTC is not present (NTC
pin tied to 0), this state is left for weak safe state. In case of
no battery, the NCP1850 stay in weak wait state (the system
is powered by DC−DC).
Weak Safe
The voltage at VBAT, is below the VSAFE threshold. In
weak safe state, the battery is charged with a linear current
source at a current of ISAFE. The DC−DC converter is
enabled and set to VCHG while the battery FET QBAT is
opened. In case the ILIM pin is not made high or the input
current limit defeated by I2C before timer expiration, the
state is left for the safe charge state after a certain amount of
time (see Wake up Timer section). Otherwise, the state
machine will transition to the weak charge state once the
battery is above VSAFE.
Batfet Detection
Weak Charge
The presence of a PMOS (QBAT) at the FET pin is verified
by the charging process during its config state. To
distinguish the two types of applications, in case of no
battery FET the pin FET is to be tied to ground. In the config
state an attempt will be made to raise the FET pin voltage
slightly up to a detection threshold. If this is successful it is
considered that a battery FET is present. The batfet detection
is completed for the whole charge cycle and will be done
again upon unplug condition (VBAT < VINDET or VIN −
VBAT < VCHGDET) or register reset (register CTRL1– bit
REG_RST).
The voltage at VBAT, is above the VSAFE threshold. The
DC−DC converter is enabled and set to VCHG. The battery
is initially charged at a charge current of IWEAK supplied by
a linear current source from WEAK pin (i.e. DC−DC
converter) to BAT pin. IWEAK value is programmable
(register MISC_SET bits IWEAK). The weak charge timer
(see Wake up Timer section) is no longer running. When the
battery is above the VFET threshold (programmable), the
state machine transitions to the full charge state thus
BATFET QBAT is closed.
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NCP1850
VBAT
IOUT
VCHG
ICHG
VRECHG
VSYS
IBAT
IWEAK
VBAT
VFET
IBAT
ISYS
IEOC
ISAFE
VSAFE
Weak
Wait
Weak
Safe
Weak
Charge
Constant
Current
Constant
Voltage
End of
Charge
Figure 7. Weak Charge Profile
In some application cases, the system may not be able to
start in weak charge states due to current capability
limitation or/and configuration of the system. If so, in order
to avoid unexpected “drop and retry” sequence of the buck
output, the charge state machine allows only three system
power−up sequences based on SPM pin level: If SPM pin
level is toggled three times during weak charge states, the
system goes directly to safe charge state and a full charge
mode sequence is initiated (“Power fail” condition in
Charging process section).
safety timer (Watchdog timer, Charge timer, Wakeup timer
and USB timer) are detailed below. When a timer expires
(condition “timeout” in Charging process section), the
charge process is halted.
Watchdog Timer
Watchdog timer ensures software remains alive once it
has programmed the IC. The watchdog timer is no longer
running since I2C interface is not available. Upon an I2C
write, automatically a watchdog timer TWD is started. The
watchdog timer is running during charger active states and
fault state. Another I2C write will reset the watchdog timer.
When the watchdog times out, the state machine reverts to
fault state and reported through I2C interface (register
CHINT2– bit WDTO). Also used to time out the fault state.
This timer can be disabled (Register CTRL2 bit
WDTO_DIS).
Power Path Management
Power path management can be supported when a battery
FET (QBAT) is placed between the application and the
battery. When the battery is fully charged (end of charge
state), power path management disconnects the battery from
the system by opening QBAT, while the DC−DC remains
active. This will keep the battery in a fully charged state with
the system being supplied from the DC−DC. If a load
transient appears exceeding the DC−DC output current and
thus causing VSENSEN to fall below VRECHG, the FET QBAT
is instantaneously (Within TPPM, see Electrical
Characteristics) closed to reconnect the battery in order to
provide enough current to the application. The FET QBAT
remains closed until the end of charge state conditions are
reached again or manually set through I2C (register CRTL2
bit CHG_HALT = 1) . The power path management function
is enabled through the I2C interface (register CRTL2 bit
PWR_PATH = 1).
Charge Timer
A charge timer TCHG is running that will make that the
overall charge to the battery will not exceed a certain amount
of energy. The charge timer is running during charger active
states and halted during charger not active states (see
Charging process section). The timer can also be cleared any
time through I2C (register CTRL1 – bit TCHG_RST). The
state machine transitions to fault state when the timer
expires. This timer can be disabled (Register CTRL2 bit
CHGTO_DIS).
USB Timer
A USB charge timer TUSB is running in the charger active
states while halted in the charger non active states. The timer
keeps running as long as the lowest input current limit
Safety Timer Description
The safety timer ensures proper and safe operation during
charge process. The set and reset condition of the different
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NCP1850
remains selected either by ILIM pin or I2C (register I_SET
– bit IINLIM and IINLIM_EN). This will avoid exceeding
the maximum allowed USB charge time for un−configured
connections. When expiring, the state machine will
transition to fault state. The timer is cleared in the off state
or by I2C command (register CTRL1 – bit TCHG_RST).
Input current limitation
In order to be USB specification compliant, the input
current at VIN is monitored and could be limited to the
IINLIM threshold. The input current limit threshold is
selectable through the ILIMx pin. When low, the one unit
USB current is selected (IIN ≤ 100 mA), where when made
high 5 units are selected (IIN ≤ 500 mA). In addition, this
current limit can be programmed through I2C (register
MISC_SET bits IINLIM) therefore defeating the state of the
ILIMx pin. In case of non−limited input source, current limit
can be disabled (register CTRL2 bit IINLIM_EN). The
current limit is also disabled in case the input voltage
exceeds the VBUSOV threshold.
Wake up Timer
Before entering weak charge state, NCP1850 verifies if
the input current available is enough to supply both the
application and the charge of the battery. A wake−up timer
TWU verifies if ILIM pin is raised fast enough or application
powered up (by monitoring register I_SET – bit IINLIM and
IINLIM_EN level) after a USB attachment. The wake up
timer is running in weak wait state and weak safe state and
clears when the input current limit is higher than 100 mA.
IBAT
VBAT
VCHG
VRECHG
ICHG
IPRE
VPRE
IEOC
ISAFE
VSAFE
Safe
Charge
Pre
Charge
Constant
Current
Constant
Voltage
End of
Charge
Figure 8. Typical Charging Profile of NCP1850 with Input Current Limit
Input Voltage Based Automatic Charge Current
‘1’ (register NTC_TH_SENSE). Knowing this, the user is
free to halt the charge (register CTRL − bit CHG_EN) or
reduce the charge current (register I_SET − bits ICHG).
When chip temperature reaches TSD value, the charge
process is automatically halt.
Between TWARN and TSD threshold, a junction
temperature management option is available by setting 1 to
TJ_WARN_OPT bit (register CONTROL). In this case, if
the die temperature hits TM1 threshold, an interrupt is
generated again but NCP1850 will also reduce the charge
current ICHG by two steps or 200 mA. This should in most
cases stabilize the die temperature because the power
dissipation will be reduced by approximately 50 mW. If the
die temperature increases further to hit TM2, an interrupt is
generated and the charge current is reduced to its lowest
If the input power source capability is unknown,
automatic charge current will automatically increase the
charge current step by step until the VIN drops to VBUSUV.
Upon VBUSUV being triggered, the charge current ICHG is
immediately reduced by 1 step and stays constant until VIN
drops again to VBUSUV. The ICHG current is clamped to the
I2C register value (register IBAT_SET, bits ICHG). This
unique feature is enabled through I2C register (register
CRTL2 bit AICL_EN).
Junction temperature management
During the charge process, NCP1850 monitors the
temperature of the chip. If this temperature increases to
TWARN, an interrupt request (described in section Charge
status reporting) is generated and bit TWARN_SNS is set to
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NCP1850
Regulated Power Supply (Trans pin)
level or 400mA. The initial charge current will be
re−established when the die temperature falls below the
TWARN again.
If bit TJ_WARN_OPT = 0 (register CTRL1), the charge
current is not automatically reduced, no current changes
actions are taken by the chip until TSD.
NCP1850 has embedded a linear voltage regulator
(VTRANS) able to supply up to ITRMAX to external loads.
This output can be used to power USB transceiver. Trans pin
is enabled if a VBUS valid is connected on input pin
(VBUSUV < VIN < VBUSOV) and can be disabled through I2C
(bit TRANS_EN_REG register CTRL2). A current limiter
protects the IC in case of short circuit on TRANS pin.
Battery Temperature Management
For battery safety, charging is not allowed for too cold or
too hot batteries. The battery temperature is monitored
through a negative temperature coefficient (NTC)
thermistor mounted in the battery pack or on the phone PCB
close to the battery pack. In some cases the NTC is handled
by the platform and will not be connected to the charger IC.
NCP1850 provides a NTC pin for monitoring an external
NTC thermistor. NTC pin is connected to an internal voltage
VREG through pull−up resistor (RNTCPU). By connecting a
NTC thermistor between NTC pin and GND, internal
comparators can monitors voltage variation and provides
temperature information to the state machine.
Charge Status Reporting
Charge Status on FLAG Pin
FLAG pin is used to report charge status to the system
processor and also for interruption request.
During charger active states and wait state, the pin FLAG
is low in order to indicate that the charge of the battery is in
progress. When charge is completed or disabled or a fault
occurs, the FLAG pin is high as the charge is halted.
Interruption on FLAG pin
Upon any state or status change, the system controller can
be informed by sensing FLAG pin. A TFLAGON pulse is
generated on this pin in order to signalize all events listed in
the STAT_INT, CH1_INT, CH2_INT, BST_INT registers.
All these bits are read to clear. The register map indicated the
active transition of each bits (column “TYPE” Register Map
section).
If more than 1 interrupt appears, only 1 pulse is generated
while interrupt registers (STAT_INT, CH1_INT, CH2_INT,
BST_INT) will not fully clear.
The level of this pulse depends on the state of the charger
(see Charging process section):
− When charger in is charger active states and wait state
the FLAG is low and consequently the pulse level on
FLAG pin is high.
− In the others states, the pulse level is low as the FLAG
stable level is high.
This Pulse can be globally masked due to the
INT_FLG_MASK bit (Register CTRL1).
VREG
RNTCPU
+
− V
RMOVED
+
− V
COLD
+
−
−
+
−
+
−
+
NTC
VCHILLY
+
VWARM
VHOT
VNTCDIS
NCP1850
Figure 9. NTC Monitoring Circuit
Interruption on INTB Pin
Two thresholds ‘cold’ and ‘hot’ are provided those are
programmable. The corresponding voltage levels of these
thresholds are respectively VCOLD and VHOT. Interrupts
(describe in section Charge status reporting) are generated
when crossing either threshold. The charge is halted outside
the cold−hot window. In addition to the above, comparators
monitor the NTC presence. When the NTC is removed
(VNTC > VNTCRMV) , no more charge current is supplied to
the battery and an interrupt is generated (describe in section
Charge status reporting). This functionality can be disabled
through programming (bit NTC_EN in register CTRL1).
When the NTC is not used in the application the NTC pin can
be tied to ground (VNTC < VNTCDIS) which will disable the
battery temperature monitoring function.
Upon any state or status change, the system controller can
be informed by sensing INTB pin. This pin is tied low in
order to signalize all events listed in the STAT_INT,
CH1_INT, CH2_INT, BST_INT registers and can be
individually masked with the corresponding mask bits in
registers STAT_MSK, CH1_MSK, CH2_MSK and
BST_MSK. All interrupt signals on INTB pin can be
masked with the global interrupt mask bit (bit INT_MASK
register CTRL1). All these bits are read to clear. The register
indicated the active transition of each bits (column “TYPE”
Register Map section).
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NCP1850
If more than 1 interrupt appears, the INTB pin stay low
while interrupt registers (STAT_INT, CH1_INT, CH2_INT,
BST_INT) will not fully clear.
If the battery is equipped with an NTC its removal is
detected (VNTC > VNTCRMV) and the state machine transits
to fault state and an interrupt is generated (bit BATRMV
register CH1_INT). Then, in case of applications with
BATFET, the state machine will end up in weak wait state so
the system is powered by the DC−DC converter (see Weak
Wait section) without battery. In case of application without
BATFET, the state machine will end up in fault state
(DC−DC off) so the system is not powered.
With a battery pack without NTC support, the voltage at
VBAT will rapidly reach the DCDC converter setting VCHG
and then transition to end of charge state causing DC−DC
off. Thus VBAT falls (“Battery fail” condition in Charging
Process section).
STATUS and CONTROL Registers
The status register contains the current charge state, NTC
and BATFET connection as well as fault and status interrupt
(bits INT_REG in register STATUS). The charge state (bits
STATE in register STATUS) is updated on the fly and
corresponds to the charging state describe in Charging
Process section. An interruption (see description below) is
generated upon a state change. In the config state, hardware
detection is performed on BAFTET and NTC pins. From
wait state, their statuses are available (bit BATFET and NTC
in register STATUS). INT_REG bits are different to 0 if an
interruption appears (see description below). Thanks to this
register, the system controller knows the chip status with
only one I2C read operation. If a fault appears or a states
change the controller can read corresponding registers for
more details.
Factory Mode
During factory testing no battery is present in the
application and a supply could be applied through the
bottom connector to power the application. The state
machine will support this mode of operation under the
condition that the application includes a battery FET and
uses batteries with NTC support (similar as no battery
operation). In this case, the state machine will end up in weak
wait state (see Weak Wait section). The application is
supplied while the absence of the battery pack is interpreted
as a battery pack out of temperature (VNTC > VCOLD).
Through I2C the device is entirely programmable so the
controller can configure appropriate current and voltage
threshold for handle factory testing. Factory regulation
mode (Register MISC_SET Bit FCTRY_MOD_REG) is
accessible for factory testing purpose. In this mode, input
and charge current loops are disabled, allowing full power
to the system.
Sense and Status Registers
At any time the system processor can know the status of
all the comparators inside the chip by reading VIN_SNS,
VBAT_SNS, and TEMP_SNS registers (read only). These
bits give to the system controller the real time values of all
the corresponding comparators outputs (see BLOCK
DIAGRAM).
Battery Removal and No Battery Operation
During normal charge operation the battery may bounce
or be removed. The state transition of the state machine only
occurs upon deglitched signals which allow bridging any
battery bounce. True battery removal will last longer than
the debounce times. The NCP1850 responses depend on
NTC and BATFET presence:
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NCP1850
CHARGING PROCESS
CHARGER ACTIVE: WEAK CHARGE MODE
CHARGER NOT ACTIVE MODE
WEAK WAIT
− BUCK: ON
− IWEAK : OFF
− ISAFE: OFF
− FLAG : LOW
− QFET: OFF
VCAP > VSYSUV
OFF
−VIN < VINDET or
−VIN − VBAT < VCHGDET
− Charger OFF IQ < IOFF
− [email protected] available
Halt Charging :
VNTC > VCOLD or
VNTC < VWARM
Start Charging :
VNTC < VCOLD or
VNTC > VWARM
ANY STATE
WEAK SAFE
−VIN > VINDET and
−VIN − VBAT > VCHGDET
Batfet present
and VBAT < VFET
and SPM = 0
REG_RST = 1
CONFIG
− BUCK: ON
− IWEAK : OFF
− ISAFE: ON
− FLAG : LOW
− QFET: OFF
− Power−up
− NTC and BATFET detection
− Q1: ON
VNTC > VCOLD or
VNTC < VWARM or
VBAT > VSAFE
VBAT > VSAFE and
w
IINLIM 500mA
WEAK CHARGE
−VIN > VINOV or
−VBAT >VBUCKOV or −
Timeout or
-Power fail or
−TJ >TSD or
−CHR_EN = 0
Power−up and
detection done
Fault removed
and CHR_EN = 1
WAIT
− BUCK: OFF
− IWEAK : OFF
− ISAFE: OFF
− FLAG : LOW
− QFET: ON
− BUCK: ON
− IWEAK : ON
− ISAFE: OFF
− FLAG : LOW
− QFET: OFF
−Timeout
−TJ >TSD or
−VIN > VINOV or
−VBAT >VBATOV or
−CHR_EN = 0
FAULT
−BUCK: OFF
−IWEAK : OFF
−ISAFE: OFF
−FLAG : HIGH
−QFET: ON
−Timeout
−TJ >TSD or
−VIN > VINOV or
−VBAT >VBUCKOV or
−VNTC > VNTCRMV or
−CHR_EN = 0
−TJ >TSD or
−VIN > VINOV or
−VNTC > VNTCRMV or
−CHR_EN = 0
END OF CHARGE
− BUCK: OFF*
− IWEAK : OFF
− ISAFE: OFF
− FLAG : HIGH
− QFET: ON*
VBAT >VFET
FULL CHARGE
− BUCK: ON
− IWEAK :OFF
− ISAFE: OFF
− FLAG : LOW
− QFET: ON
−VBAT < VRECHG
−VBAT > VRECHG and
−( BAT < IEOC or CHG_HALT)
VBAT >
VPRE
VBAT <
VPRE
−VBAT > VRECHG and
− (IBAT < IEOC or CHG_HALT)
−VSENSN < VRECHG and
- pwr_path = 1
PRE CHARGE
− BUCK: ON (precharge)
− IWEAK :OFF
− ISAFE: OFF
− FLAG : LOW
− QFET: ON
−VBAT < VRECHG
DPP
Halt Charging :
VNTC > VCOLD or
VNTC < VWARM or
Battery fail
− BUCK: ON
− IWEAK : OFF
− ISAFE: OFF
− FLAG : HIGH
− QFET: ON
VBAT >
VSAFE
VBAT <
VSAFE
Timeout
SAFE CHARGE
− BUCK: OFF
− IWEAK : OFF
− ISAFE: ON
− FLAG : LOW
− QFET: ON
Start Charging :
VCOLD > VNTC > VWARM
CHARGER ACTIVE: FULL CHARGE MODE
* See Power Path Management section.
Figure 10. Detailed Charging Process
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NCP1850
Boost Mode Operation
turns off the PWM converter. A fault is indicated to the
system controller (bit VBATLO register BST_INT)
A toggle on OTG pin or OTG_EN bit (register CTRL1) is
needed to start again a boost operation.
The DC−DC Converter can also be operated in a Boost
mode where the application voltage is stepped up to the input
VIN for USB OTG supply. The converter operates in a
1.5 MHz fixed frequency PWM mode or in pulse skipping
mode under low load condition. In this mode, where CAP is
the regulated output voltage, Q3 is the main switch and Q2
is the synchronous rectifier switch. While the boost
converter is running, the Q1 MOSFET is fully turned ON.
Boost Status Reporting
STATUS and CTRL registers
The status register contains the boost status. Bits STATE
in register STATUS gives the boost state to the system
controller. Bits FAULTINT and STATINT in register
STATUS are also available in boost mode. If a fault appears
or a status changes (STATINT bits and FAULTINT) the
processor can read corresponding registers for more details.
Interruption
In boost mode, valid interrupt registers are STAT_INT and
BST_INT while CH1_INT and CH2_INT are tied to their
reset value. Upon a state or status changes, the system
controller is informed by sensing FLAG or INTB pins. Like
in charge mode, TFLAGON pulse is generated on FLAG pin
and low level is applied on INTB pin in order to signalize the
event. The pulse level is low as the FLAG level is high in
boost mode. Charge state transition even and all signals of
register BST_INT can generate an interrupt request on
INTB pin and can be masked with the corresponding mask
bits in register BST_MSK. All these bits are read to clear.
The register map indicates the active transition of each bits
(column “TYPE” in see Register Map section). If more than
one interrupt appears, INTB stay low while interrupt
registers (listed just above) will not fully clear.
Sense and status registers
At any time the system controller can know the status of
all the comparator inside the chip by reading VIN_SNS and
TEMP_SNS registers (read only). These bits give to the
controller the real time values of all the corresponding
comparators outputs (see BLOCK DIAGRAM).
Boost Start−up
The boost mode is enabled through the OTG pin or I2C
(register CTRL1 − bit OTG_EN). Upon a turn on request, the
converter regulates CAP pin, and the output voltage is
present on IN pin through the Q1 MOSFET which is
maintained close unless OVLO event. During start−up
phase, if the IN pin cannot reach voltage higher than 4.65V
within 16ms, then a fault is indicated to the system controller
(bit VBUSILIM register BST_INT) and the boost is
turns−off.
VIN Over−Voltage Protection
The NCP1850 contains integrated over−voltage
protection on the VIN line. During boost operation (VIN
supplied), if an over−voltage condition is detected (VIN >
VBUSOV), the controller turns off the PWM converter.
OTG_EN bit (register CTRL1) is set to 0 and a fault is
indicated to the system controller (bit VBUSOV register
BST_INT)
VIN Over−Current Protection
The NCP1850 contains over current protection to prevent
the device and battery damage when VIN is overloaded.
When the IN voltage drops down to VBUSUV, NCP1850
determine an over−current condition is met, so Q1 MOSFET
and PWM converter are turned off. A fault is indicated to the
system controller (bit VBUSILIM register BST_INT).
Battery Under−Voltage Protection
During boost mode, when the battery voltage is lower than
the battery under voltage threshold (VBAT < VIBSTL), the IC
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NCP1850
I2C description
NCP1850 can support a subset of I2C protocol, below are detailed introduction for I2C programming.
FROM MCU to NCPxxxx
FROM NCPxxxx to MCU
START
IC ADRESS
1
ACK
0
ACK
DATA 1
ACK
DATA n
/ACK
STOP
READ OUT FROM PART
STOP
WRITE INSIDE PART
1 à READ
/ACK
START
IC ADRESS
DATA 1
ACK
DATA n
ACK
If PART down not Acknowledge, the /NACK will be followed b a STOP or Sr
If PART Acknowledges, the ACK can be followed by another data or Stop or Sr
0 à WRITE
Figure 11. General Protocol Description
The first byte transmitted is the Chip address (with LSB bit sets to 1 for a read operation, or sets to 0 for a Write operation).
Then the following data will be:
− In case of a Write operation, the register address (@REG) we want to write in followed by the data we will write in the
chip. The writing process is incremental. So the first data will be written in @REG, the second one in @REG + 1 .
The data are optional.
− In case of read operation, the NCP1850 will output the data out from the last register that has been accessed by the last
write operation. Like writing process, reading process is an incremental process.
Read Out from Part
The Master will first make a “Pseudo Write” transaction with no data to set the internal address register. Then, a stop then start
or a Repeated Start will initiate the read transaction from the register address the initial write transaction has set:
FROM MCU to NCPxxxx
FROM NCPxxxx to MCU
STETS INTERNAL
REGISTER POINTER
START
IC ADRESS
0
ACK
REGISTER ADRESS
ACK
STOP
0 à WRITE
START
IC ADRESS
1
ACK
ACK
DATA 1
REGISTER ADRESS
VALUE
DATA n
/ACK
STOP
REGISTER ADRESS + (n − 1)
VALUE
n REGISTERS READ
1 à READ
Figure 12. Read Out from Part
The first WRITE sequence will set the internal pointer on the register we want access to. Then the read transaction will start
at the address the write transaction has initiated.
Write in Part:
Write operation will be achieved by only one transaction. After chip address, the MCU first data will be the internal register
we want access to, then following data will be the data we want to write in Reg, Reg + 1, Reg + 2, ., Reg +n.
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NCP1850
Write n Registers:
FROM MCU to NCPxxxx
FROM NCPxxxx to MCU
SETS INTERNAL
REGISTER POINTER
START
IC ADRESS
0
ACK
WRITE VALUE IN
REGISTER REG + (n−1)
WRITE VALUE IN
REGISTER REG0
ACK
REGISTER REG0 ADRESS
ACK
REG VALUE
ACK
REG + (n−1) VALUE
STOP
n REGISTERS WRITE
0 à WRITE
Figure 13. Write in n Registers
I2C Address
NCP1851 has fixed I2C but different I2C address (0$10, 7 bit address, see below table A7~A1), NCP1851 supports 7−bit
address only.
Table 5. NCP1850 I2C ADDRESS
I2C Address (Note 10)
Default
Hex
A7
A6
A5
A4
A3
A2
A1
A0
$6C / $6D
0
1
1
0
1
1
0
X
10. Other addresses are available upon request.
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
Function
STATUS REGISTER − Memory Location: 00
7−4
R
No_Reset
STATE[3:0]
0000
Charge mode:
−0000: OFF
−0001: WAIT + STBY
−0010: SAFE CHARGE
−0011: PRE CHARGE
−0100: FULL CHARGE
−0101: VOLTAGE CHARGE
−0110: CHARGE DONE
−0111: DPP
−1000: WEAK WAIT
−1001: WEAK SAFE
−1010: WEAK CHARGE
−1011: FAULT
Boost mode:
−1100: BOOST WAIT(s_WAIT)
−1101: BOOST MODE (s_ON)
−1110: BOOST FAULT( s_FAULT)
−1111: BOOST OVER LOAD (s_OL))
3
R
No_Reset
BATFET
0
Indicate if a batfet is connected:
0: No BATFET is connected
1: BATFET is connected.
2
R
No_Reset
NTC
0
Indicate if a ntc resistor is present:
0: No NTC connected
1: NTC connected
1
R
No_Reset
STATINT
0
Status interrupt:
0: No status interrupt
1: Interruption flagged on STAT_INT register
0
R
No_Reset
FAULTINT
0
Fault interrupt:
0: No status interrupt
1: interruption flagged on CHRIN1, CHRIN2 or
BST_INT register
REG_RST
0
Reset:
0: No reset
1: Reset all registers
CTRL1 REGISTER − Memory Location: 01
7
RW
OFF STATE, POR,
REG_RST
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NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
Function
CTRL1 REGISTER − Memory Location: 01
6
RW
OFF STATE, POR,
REG_RST
CHG_EN
1
Charge control:
0: Halt charging (go to fault state) or OTG
operation
1: Charge enabled / Charge resume
5
RW
OFF STATE, POR,
REG_RST,
CHGMODE
OTG_EN
0
On the go enable:
0: no OTG operation
1: OTG operation (set by I2C or OTG pin)
4
RW
OFF STATE, POR,
REG_RST
NTC_EN
1
ntc pin operation enable:
0:Battery temperature ignore,
1: Battery temperature modify the charge profile.
3
RW
OFF STATE, POR,
REG_RST
TJ_WARN_OPT
0
Enable charge current vs Junction temperature
0: No current change versus junction temperature
1: Charge current is reduced when TJ is too high.
2
RW
OFF STATE, POR,
REG_RST
CHG_HALT
0
Force End of Charge
0: Normal End of charge condition
1: Force EOC condition if VBAT > VRECHG
1
RW
OFF STATE, POR,
REG_RST,
TRM_RST
TCHG_RST
0
Charge timer reset:
0: no reset
1: Reset and resume charge timer (tchg
timer)(self clearing)
0
RW
OFF STATE, POR,
REG_RST
INT_MASK
1
INTB global interrupt mask
0: All Interrupts can be active.
1: All interrupts are not active
CTRL2 REGISTER − Memory Location: 02
7
RW
OFF STATE, POR,
REG_RST,
OTGMODE
WDTO_DIS
0
Disable watchdog timer
0: Watchdog timer enable
1: Watchdog timer disable
6
RW
OFF STATE, POR,
REG_RST,
OTGMODE
CHGTO_DIS
0
Disable charge timer
0: Charge timer enable
1: Charge timer disable
5
RW
OFF STATE, POR,
REG_RST,
OTGMODE
PWR_PATH
0
Power Path Management:
0: Power Path disable
1: Power Path enable
4
RW
OFF STATE, POR,
REG_RST
TRANS_EN_REG
1
Trans pin operation enable:
0 : Trans pin is still off
1 : Trans pin is supply
3
RW
OFF STATE, POR,
REG_RST
INT_FLG_MASK
1
FLAG global interrupt mask
0 : All Interrupts are active.
1 : All interrupts are not active
2
RW
OFF STATE, POR,
REG_RST,
OTGMODE
IINSET_PIN_EN
1
Enable input current set pin:
0: Input current limit and AICL control by I2C
1: Input current limit and AICL control by pins
ILIMx
1
RW
OFF STATE, POR,
REG_RST,
OTGMODE
IINLIM_EN
1
Enable input current limit:
0: No input current limit
1: Input current limit is IINLIM[3:0]
0
RW
OFF STATE, POR,
REG_RST,
OTGMODE
AICL_EN
0
Enable automatic charge current:
0: No AICL
1: AICL
0
0: Silicon temperature is below TWARN threshold
1: Silicon temperature is above TWARN
threshold
STAT_INT REGISTER − Memory Location: 03
7−6
R
No_Reset
Reserved
5
RCDual
OFF STATE, POR,
REG_RST
TWARN
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NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
Function
STAT_INT REGISTER − Memory Location: 03
4
RCDual
OFF STATE, POR,
REG_RST
TM1
0
0: Silicon temperature is below T1 threshold
1: Silicon temperature is above T1 threshold
3
RCDual
OFF STATE, POR,
REG_RST
TM2
0
0: Silicon temperature is below T2 threshold
1: Silicon temperature is above T2 threshold
2
RCDual
OFF STATE, POR,
REG_RST
TSD
0
0: Silicon temperature is below TSD threshold
1: Silicon temperature is above TSD threshold
1
R
No_Reset
RESERVED
0
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
VBUSOK
0
0
0: changer not in USB range
1: charger in USB charging range VBUSUV <
VIN < VBUSOV
CH1_INT REGISTER − Memory Location: 04
R
No_Reset
RESERVED
0
4
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
VINLO
0
VIN changer detection interrupt:
1: VIN − VBAT > VCHGDET and VIN < VINDET
3
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
VINHI
0
VIN over voltage lock out interrupt:
1: VIN > VINOV
2
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
BATRMV
0
battery temp out of range interrupt:
1: VNTC > VNTCRMV
1
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
BUCKOVP
0
VBAT over voltage interrupt:
1: VBAT > VOVP
0
R
No_Reset
CHINT2
0
charger related interrupt (CH2_INT register)
Battery Temperature exceeds NTC HOT
threshold
7−5
CH2_INT REGISTER − Memory Location: 05
7
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
NTCHOT
0
5−6
R
No_Reset
RESERVED
00
4
RCDual
OFF STATE,
REG_RST,
POR, OTGMODE
NTCCOLD
0
Battery Temperature is lower than NTC COLD
threshold
3
RCSingl
e
OFF STATE, POR,
REG_RST,
TRM_RST,
OTGMODE
WDTO
0
watchdog timeout expires interrupt:
1: 32s timer expired.
2
RCSingl
e
OFF STATE, POR,
REG_RST,
TRM_RST,
OTGMODE
USBTO
0
usb timeout expires initerrupt:
1: 2048s timer expired
1
RCSingl
e
OFF STATE, POR,
REG_RST,
TRM_RST,
OTGMODE
CHGTO
0
charge timeout expires interrupt:
1: 3600s timer expired
0
R
No_Reset
CHINT1
0
charger related interrupt (CH1_INT register)
BST_INT REGISTER − Memory Location: 06
7−3
R
No_Reset
RESERVED
00000
2
RCDual
OFF STATE, POR,
REG_RST,
CHGMODE
VBUSILIM
0
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vbus overload interrupt:
1: Vbus voltage < VBUSUV
NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
Function
BST_INT REGISTER − Memory Location: 06
1
RCDual
OFF STATE, POR,
REG_RST,
CHGMODE
VBUSOV
0
vbus overvoltage interrupt:
1: Vbus voltage < VBUSOV
0
RCDual
OFF STATE, POR,
REG_RST,
CHGMODE
VBATLO
0
vbat overvoltage interrupt:
1: Vbat voltage < VIBSTL
VIN over voltage lock out comparator
1: VIN > VINOV
VIN_SNS REGISTER − Memory Location: 07
7
R
No_Reset
VINOVLO_SNS
0
6
R
No_Reset
RESERVED
0
5
R
No_Reset
VBUSOV_SNS
0
VIN not is USB range comparator
1: VIN > VBUSOV
4
R
No_Reset
VBUSUV_SNS
0
VIN not is USB range comparator
1: VIN < VBUSUV
3
R
No_Reset
VINDET_SNS
0
VIN voltage detection comparator
1: VIN > VINDET
2
R
No_Reset
VCHGDET_SNS
0
VIN changer detection comparator
1: VIN − VBAT > VCHGDET
1
R
No_Reset
VBOOST_UV_SNS
0
VIN OTG under voltage comparator
1: VIN < VBUSUV
0
R
No_Reset
RESERVED
0
VBAT_SNS REGISTER − Memory Location: 08
7
R
No_Reset
NTC_REMOVAL_S
NS
0
NTC removal comparator :
1: Battery removal, VNTC > VNTCRMV
6
R
No_Reset
VBAT_OV_SNS
0
VBAT over voltage comparator
1: VBAT > VOVP
5
R
No_Reset
VRECHG_OK_SNS
0
VBAT recharge comparator
1: VBAT > VRECHG
4
R
No_Reset
VFET_OK_SNS
0
VBAT weak charge comparator
1: VBAT > VFET
3
R
No_Reset
VPRE_OK_SNS
0
VBAT precharge comparator
1: VBAT > VPRE
2
R
No_Reset
VSAFE_OK_SNS
0
VBAT safe comparator
1: VBAT > VSAFE
1
R
No_Reset
IEOC_OK_SNS
0
End of charge current comparator
1: ICHARGE > IEOC
0
R
No_Reset
RESERVED
0
TEMP_SNS REGISTER − Memory Location: 09
NTC cold comparator :
1: VNTC < VCOLD
7
R
No_Reset
NTC_COLD_SNS
0
5−6
R
No_Reset
RESERVED
00
4
R
No_Reset
NTC_HOT_SNS
0
NTC disable comparator :
1: VNTC > VNTCDIS
3
R
No_Reset
TSD_SNS
0
Chip thermal shut down comparator
1: Chip Temp > TSD
2
R
No_Reset
TM2_SNS
0
Chip thermal shut down comparator
1: Chip Temp > tm2
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NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
Function
TEMP_SNS REGISTER − Memory Location: 09
1
R
No_Reset
TM1_SNS
0
Chip thermal shut down comparator
1: Chip Temp > tm1
0
R
No_Reset
TWARN
0
Chip thermal shut down comparator
1: Chip Temp > twarn
STAT_MSK REGISTER − Memory Location: 0A
7−6
R
No_Reset
RESERVED
00
5
RW
OFF STATE,
POR, REG_RST
TWARN_MASK
1
TWARN interruption mask bit.
4
RW
OFF STATE,
POR, REG_RST
TM1_MASK
1
TM1 interruption mask bit.
3
RW
OFF STATE,
POR, REG_RST
TM2_MASK
1
TM2 interruption mask bit.
2
RW
OFF STATE,
POR, REG_RST
TSD_MASK
1
TSD interruption mask bit.
1
R
No_Reset
RESERVED
0
0
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VBUSOK_MASK
1
VBUSOK interruption mask bit.
CH1_MSK REGISTER − Memory Location: 0B
7−5
R
No_Reset
RESERVED
000
4
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VINLO_MASK
1
VINLO interruption mask bit.
3
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VINHI_MASK
1
VINHI interruption mask bit.
2
RW
OFF STATE, POR,
REG_RST,
OTGMODE
BATRMV_MASK
1
BATRMV interruption mask bit.
1
RW
OFF STATE, POR,
REG_RST,
OTGMODE
BUCKOVP_MASK
1
BUCKOVP interruption mask bit.
0
R
No_Reset
RESERVED
0
CH2_MSK REGISTER − Memory Location: 0C
7
RW
OFF STATE, POR,
REG_RST,
OTGMODE
NTCHOT_MASK
1
5−6
R
No_Reset
RESERVED
0
4
RW
OFF STATE, POR,
REG_RST,
OTGMODE
NTCCOLD_MASK
1
NTCCOLD interruption mask bit.
3
RW
OFF STATE, POR,
REG_RST,
OTGMODE
WDTO_MASK
0
WDTO interruption mask bit.
2
RW
OFF STATE, POR,
REG_RST,
OTGMODE
USBTO_MASK
0
USBTO interruption mask bit.
1
RW
OFF STATE, POR,
REG_RST,
OTGMODE
CHGTO_MASK
0
CHGTO interruption mask bit.
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NTCHOT interruption mask bit.
NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
RESERVED
0
Function
CH2_MSK REGISTER − Memory Location: 0C
0
R
No_Reset
BST_MSK REGISTER − Memory Location: 0D
R
No_Reset
RESERVED
0000
3
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VBUSILIM_MASK
1
VBUSILIM interruption mask bit.
2
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VBUSOV_MASK
1
VBUSOV interruption mask bit.
1
RW
OFF STATE, POR,
REG_RST,
OTGMODE
VBATLO_MASK
1
VBATLO interruption mask bit.
0
RW
OFF STATE, POR,
REG_RST,
OTGMODE
STATEOTG_MASK
1
STATEOTG interruption mask bit.
7−4
VBAT_SET REGISTER − Memory Location: 0E
7−6
R
No_Reset
RESERVED
00
0−5
RW
OFF STATE, POR,
REG_RST,
OTGMODE
CTRL_VBAT [5:0]
001100
000000: 3.3 V
001100: 3.6 V
110000: 4.5 V
Step: 0.025 V
IBAT_SET REGISTER − Memory Location: 0F
7
R
No_Reset
RESERVED
0
6−4
RW
OFF STATE, POR,
REG_RST,
OTGMODE
IEOC[2:0]
010
000: 100 mA
010: 150 mA
111: 275 mA
Step: 25 mA
RW
OFF STATE, POR,
REG_RST,
OTGMODE
ICHG[3:0]
0110
Output range current programmable range:
0000: 400 mA
1011: 1.5 A
Step : 100 mA
3−0
MISC_SET REGISTER − Memory Location: 10
7
RW
OFF STATE, POR,
REG_RST,
OTGMODE
TST_SET
0
Minimum transition time from Weak Charge to
Full Charge State
0 : 32 s
1 : 16 ms
6
RW
OFF STATE, POR,
REG_RST,
OTGMODE
FCTRY_MOD_REG
0
Factory mode :
0: Factory mode disable
1: Enable factory mode.
5
RW
OFF STATE, POR,
REG_RST,
OTGMODE
IWEAK_EN
1
Charge current during weak battery states:
0: Disable
1: 100 mA
011
Battery to system re−connection threshold:
000: 3.1 V
001: 3.2 V
010: 3.3 V
011: 3.4 V
100: 3.5 V
101: 3.6 V
00
Input current limit range:
00: 100 mA
01: 500 mA
10: 900 mA
11: 1500 mA
4−2
1−0
RW
OFF STATE, POR,
REG_RST,
OTGMODE
RW
OFF STATE, POR,
REG_RST,
OTGMODE
CTRL_VFET[2:0]
IINLIM[1:0]
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NCP1850
Table 6. REGISTERS MAP
Bit
Type
Reset
Name
RST
Value
RESERVED
0000
Function
NTC_SET REGISTER − Memory Location: 11
R
7−4
No_Reset
R0 = 10 kW, T0= 25°C
2−3
OFF STATE, POR,
REG_RST,
OTGMODE
RW
BATCOLD[1:0]
01
B = 3380
00: −1°C
01: 2°C
10: 5°C
11: 9°C
B = 3400
00: 1°C
01: 5°C
10: 8°C
11: 11°C
R0 = 10 kW,T0= 25°C
0−1
OFF STATE, POR,
REG_RST,
OTGMODE
RW
BATHOT[1:0]
10
B = 3380
|00: 43°C
01: 47°C
10: 52°C
11: 57°C
B = 3400
00: 40°C
01: 44°C
10: 48°C
11: 52°C
APPLICATION INFORMATION
Components Selection
The bandwidth is recommended to be high enough in case
of application with a BATFET because the system can be
directly connected to the buck output. And in this case, the
battery does not play any role upon a load transient as it’s
disconnected from the buck converter.
USB dedicated charge
VIN = 5 V
VCHG = 4.2 V
ICHG = 1.5 A
L1 = 2.2 mH
DIL1 = 0.189 A
IPEAKMAX = 1.59 A
AC adaptor charge
VIN = 16 V
VCHG = 4.2 V
ICHG = 1.5 A
L1 = 2.2 mH
DIL1 = 0.6 A
IPEAKMAX = 1.8 A
Resistance R1
R1 (charge current sense resistor) resistor is determined by
considering thermal constrain as its value is 68 mW typical.
The power dissipation is given by:
Inductor L1
NCP1851 is recommended to be used with 2.2 mH
inductor. Below will give inductor ripple and maximum
current for two different application cases knowing the
following relation:
ǒ
DI L + V BAT
1*
The worst case is when V BAT *
so when V BAT +
DI LMAX +
Ǔ
V BAT
V IN
L1
1
FSWCHG
V BAT 2
is maximum
V IN
V IN
2
V IN
DI
1
@
;I
+ I CHG ) LMAX
4 L1 @ F SWCHG PEAKMAX
2
Capacitor C6
A 10 mF output capacitor is recommended for proper
operation and design stability. The bandwidth of the system
is defined by the following relation:
F BW +
1
2p
ǸL 1
C6
+ 33 kHz
P R1 + R 1
(ICHG) 2
The worst case is ICHG = 1.5 A so PR1 = 0.153 W.
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NCP1850
BILL OF MATERIAL
LX 2.2mH
VBUS
D+
D−
GND
SW
IN
CIN
CBOOT
CAP
CCAP
COUT
CBOOT
NCP1850
1mF
RSNS 68mW
10mF
10nF
SYSTEM
SENSP
SENSN
4.7mF
WEAK
FET
CORE
CCORE
2.2mF
QBAT (*)
BAT
NTC
+
TRANS
CTRANS
100nF
FLAG
SCL
SDA
AGND
SPM
PGND
ILIM
INTB
OTG
Figure 14. NCP1850 Typical Application Example
Item
Part Description
Ref
Value
PCB
Footprint
Manufacturer
Manufacturer Reference
1
Ceramic Capacitor 25 V X5R
CIN
1 mF
0603
MURATA
GRM188R61E105K
2
Ceramic Capacitor 25 V X5R
CCAP
4.7 mF
0805
MURATA
GRM21BR61E475KA12L
3
Ceramic Capacitor 6.3 V X5R
CCORE
2.2 mF
0402
MURATA
GRM155R60J225M
4
Ceramic Capacitor 6.3 V X5R
CTRS
0.1 mF
0402
MURATA
GRM155R60J104K
5
Ceramic Capacitor 10 V X5R
CBOOT
10 nF
0402
MURATA
GRM155R60J103K
6
Ceramic Capacitor 6.3 V X5R
COUT
10 mF
0603
MURATA
GRM188R60J106M
7
SMD Inductor
LX
2.2mH
3012
TDK
VLS3012T−2R2M1R5
8
SMD Resistor 0.25 W, 1%
RSNS
68 mW
0603
PANASONIC
ERJ3BWFR068V
9
Power channel P−MOSFET
QBAT
30 mW
UDFN 2 *
2 mm
ON Semiconductor
NTLUS3A40PZ
PCB Layout Consideration
Particular attention must be paid with CCORE capacitor as
it’s decoupling the supply of internal circuitry including gate
driver. This capacitor must be placed between CORE pin
and PGND pin with a minimum track length.
The high speed operation of the NCP1850 demands
careful attention to board layout and component placement.
To prevent electromagnetic interference (EMI) problems,
attention should be paid specially with components CIN, LX,
CCAP, and COUT as they constitute a high frequency current
loop area. The power input capacitor CIN, connected from
IN to PGND, should be placed as close as possible to the
NCP1850. The output inductor LX and the output capacitor
COUT connected between RSNS and PGND should be placed
close to the IC. CCAP capacitor should also be place as close
as possible to CAP and PGND pin.
The high current charge path through IN, CAP, SW,
inductor L1, Resistor R1, optional BAFTET, and battery
pack must be sized appropriately for the maximum charge
current in order to avoid voltage drops in these traces. An
IWEAK current can flow through WEAK and BAT traces
witch defines the appropriate track width.
It’s suggested to keep as complete ground plane under
NCP1850 as possible. PGND and AGND pin connection
must be connected to the ground plane.
Care should be taken to avoid noise interference between
PGND and AGND. Finally it is always good practice to keep
the sensitive tracks such as feedbacks connections (SENSP,
SENSN, BAT) away from switching signal connections by
laying the tracks on the other side or inner layer of PCB.
http://onsemi.com
28
NCP1850
IN
Power path
Q1
Q2
CORE
CIN
1mF
CCORE
Noise sensitive path
68m
SW
CAP
2.2mF
LX
2.2mF
RSNS 68mW
Q3
4.7mF
+
10mF
CCAP
CSYS
NCP1850
PGND
Figure 15. NCP1850 Power Path
ORDERING INFORMATION
Part Number
NCP1850FCCT1G
I2C Address
Package
Shipping†
$6C
WLCSP25
(Pb−Free)
TBD
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
http://onsemi.com
29
NCP1850
PACKAGE DIMENSIONS
WLCSP25, 2.06x2.06
CASE 567FZ
ISSUE O
ÈÈ
PIN A1
REFERENCE
D
A
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ASME Y14.5M, 1994.
2. CONTROLLING DIMENSION: MILLIMETERS.
3. COPLANARITY APPLIES TO SPHERICAL
CROWNS OF SOLDER BALLS.
B
E
2X
DIE COAT
A3
DIM
A
A1
A2
A3
b
D
E
e
0.10 C
A2
2X
0.10 C
DETAIL A
TOP VIEW
MILLIMETERS
MIN
MAX
−−−
0.60
0.17
0.23
0.36 REF
0.04 REF
0.24
0.29
2.06 BSC
2.06 BSC
0.40 BSC
A2
DETAIL A
0.10 C
A
RECOMMENDED
SOLDERING FOOTPRINT*
0.05 C
NOTE 3
25X
A1
SEATING
PLANE
A1
PACKAGE
OUTLINE
e
b
0.05 C A B
0.03 C
C
SIDE VIEW
E
e
0.40
PITCH
D
C
25X
0.40
PITCH
B
A
1
2
3
4
0.25
DIMENSIONS: MILLIMETERS
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and
Mounting Techniques Reference Manual, SOLDERRM/D.
5
BOTTOM VIEW
ON Semiconductor and
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC owns the rights to a number of patents, trademarks,
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any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture
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PUBLICATION ORDERING INFORMATION
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30
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For additional information, please contact your local
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NCP1850/D