BELLING BL4054 800ma standalone linear li-ion battery charger Datasheet

BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
resistor is needed, and no blocking diode is
required due to the internal MOSFET architecture.
Thermal feedback regulates the charge current to
limit the die temperature during high power
operation or high ambient temperature. The
charge voltage is fixed at 4.2V, and the charge
current can be programmed externally with a
single resistor. The BL4054/BL4054B automatical
-ly terminates the charge cycle when the charge
current drops to 1/10 the programmed value after
the final float voltage is reached.
FEATURES
Programmable Charge Current Up to 800mA
No MOSFET, Sense Resistor or Blocking
Diode Required
Preset 4.2V Charge Voltage with ±1%
Accuracy
Charge Current Monitor Output for Gas
Gauging
Thermal Regulation Maximizes Charge Rate
Without Risk of Overheating
Charges Single Cell Li-Ion Batteries Directly
from USB Port
Over-Voltage Protect
Automatic Recharge
Charge Status Output Pin
C/10 Charge Termination
25µA Supply Current in Shutdown
2.9V Trickle Charge Threshold
Soft-Start Limits Inrush Current
Available in 5-Lead SOT-23 Package
When the input supply (wall adapter or USB
supply) is removed, the BL4054/BL4054B
automatically enters a low current state, dropping
the battery drain current to less than 2µΑ. The
BL4054/BL4054B can be put into shutdown mode,
reducing the supply current to 25µA. Other
features include charge current monitor,
under-voltage lockout, automatic recharge and a
status pin to indicate charge termination and the
presence of an input voltage.
APPLICATIONS
The only difference between BL4054 and
BL4054B is that at power on, BL4054 will check
the battery voltage first, it will not start charging
unless the battery voltage is below the
auto-rechrage threshold. BL4054B does not
perform this check. So BL4054B can guarantee
the high battery capacity at all time, while BL4054
can prevent the battery from being repeatedly
charged in some specific applications.
Cellular and Smart Phones
Charging Docks and Cradles
BlueTooth Applications
PDAs
MP3/MP4/MP5 Players
DESCRIPTION
The BL4054/BL4054B is a complete constant
current / constant voltage linear charger for single
cell Lithium-Ion batteries. No external sense
ORDERING INFORMATION
TYPICAL APPLICATION
VCC
4.5V to 6.5V
BL4054/BL4054B – XX X X XXX
Package:
RN: SOT23-5
TRN: TSOT23-5
VCC
1uF
BAT
Features:
P: Standard (default, lead free)
C: Customized
600mA
BL4054/BL4054B
PROG
Trickle Charge:
T: Trickle Charge
N: No Trickle Charge
GND
Float Voltage:
42: 4.2V
43: 4.3V
44: 4.4V
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
4.2V
Li-Ion
Battery
1.65k
600mA Application Circuit
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
1
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Absolute Maximum Rating (Note 1)
Input Supply Voltage (VCC)
PROG Voltage
BAT Voltage
CHRGb
BAT Short-Circuit Duration
BAT Pin Current
-0.3V to +10V
-0.3V to +VCC
-0.3V to 7V
-0.3V to 10V
Continuous
800mA
PROG Pin Current
800µA
Maximum Junction Temperature
125°C
(Note2)
Operating Temperature Range
-40°C to 85°C
Storage Temperature Range
-65°C to 125°C
Lead Temperature (Soldering, 10s)
300°C
Package Information
TSOT23-5/SOT23-5
TOP VIEW
CHRGb 1
Part Number
PROG
4
VCC
MARKING
GND 2
BAT
5
3
Top Mark
Temp Range
(Note3)
BL4054-4.2
BAYW
BL4054-4.3
BBYW
BL4054-4.4
BCYW
BL4054B-4.2
BAYW
BL4054B-4.3
BBYW
BL4054B-4.4
BCYW
-40°C to +85°C
Thermal Resistance (Note 4)
Package
TSOT23-5
SOT23-5
ӨJA
220°C/W
250°C/W
ӨJC
110°C/W
130°C/W
Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.
Note 2: The BL4054/BL4054B is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the –40°C to
85°C operating temperature range are assured by design, characterization and correlation with statistical process controls.
Note 3: X: Product Code(BL4054:B,BL4054B:B ) V: Voltage Code(4.2V:A,4.3V:B,4.4V:C) Y: Year of Manufacturing(9:2009) W: Week of
Manufacturing(W:A-Z, a-z). Contact Belling marketing for more information in detail.
Note 4: Thermal Resistance is specified with approximately 1 square of 1 oz copper.
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
2
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Pin Description
PIN
NAME
1
CHRGb
2
GND
3
BAT
4
VCC
5
PROG
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
FUNCTION
Open-Drain Charge Status Output. When the battery is
charging, the CHRGb pin is pulled low by an internal
N-channel MOSFET. When the charge cycle is
completed, a weak pull-down of approximately 12µA is
connected to the CHRGb pin, indicating an “AC present”
condition. When the BL4054/BL4054B detects an
under-voltage lockout condition, CHRGb is forced high
impedance.
Ground
Charge Current Output. Provides charge current to the
battery and regulates the final float voltage to 4.2V. An
internal precision resistor divider from this pin sets the
float voltage which is disconnected in shutdown mode.
Positive Input Supply Voltage. Provides power to the
charger. VCC can range from 4.25V to 6.5V and should be
bypassed with at least a 1µF capacitor. When VCC drops
to within 30mV of the BAT pin voltage, the
BL4054/BL4054B enters shutdown mode, dropping IBAT to
less than 2µA.
Charge Current Program, Charge Current Monitor and
Shutdown Pin. The charge current is Programmed by
connecting a 1% resistor, RPROG, from this pin to ground.
When charging in constant-current mode, this pin servos
to 1V. In all modes, the voltage on this pin can be used to
measure the charge current using the following formula:
IBAT = (VPROG / RPROG) • 1000
The PROG pin can also be used to shut down the
charger. Disconnecting the Program resistor from ground
allows a 3µA current to pull the PROG pin high. When it
reaches the 1.21V shutdown threshold voltage, the
charger enters shutdown mode, charging stops and the
input supply current drops to 25µA. This pin is also
clamped to approximately 2.4V. Driving this pin to
voltages beyond the clamp voltage will draw currents as
high as 1.5mA. Reconnecting RPROG to ground will return
the charger to normal operation.
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
3
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Block Diagram
120oC
TDIE
VCC
+
4
TA
1x
1000x
7.0V
BAT
+
-
5µΑ
+
MA
3
R1
-
OVP
+
VA
CA
-
-
+
OV_SHDN
SHDN
C1
R2
REF
1.21V
+
R3
1V
R4
1
+
0.1V
-
R5
C2
CHRGb
STANDBY
+
C3
-
TO
BAT
BL4054/BL4054B Rev 1.4
5/2009
VCC
2.9V
5
PPMIC BU
3µΑ
PROG
GND
RPROG
2
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
4
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Electrical Characteristics (Note 5)
Symbol
(VCC = 5V, TA = 25°C, unless otherwise noted.)
Parameter
Conditions
Charge Mode Supply Current
ISPLYCHRG
(Note6)
Min
RPROG=2kΩ
RPROG =10kΩ
Typ
500mA
100mA
2000µA
2000µA
535mA
107mA
1V
1V
1.07V
1.07V
100µA
500µA
-2.5µA
-6µA
300µA
RPROG =2kΩ 465mA
RPROG =10kΩ 93mA
Max
IBATCHRG
Charge Mode Battery Current
VPROGCHRG
PROG Pin Voltage
ISPLYSTBY
Standby Mode Supply Current
IBATSTBY
Standby Mode Battery Current
ISPLYMSD
Manual Shutdown Mode Supply Current
IBATMSD
Manual Shutdown Mode Battery Current
-2µA
VPROGCLMP
PROG Pin Clamp Voltage
2V
ISPLYASD
Automatic Shutdown Mode Supply
Current
IBATASD
Automatic Shutdown Mode Battery
Current
ISPLYUVLO
UVLO Mode Supply Current
IBATUVLO
UVLO Mode Battery Current
-2µA
2µA
IBATSLEEP
Sleep Mode Battery Current
-1µA
1µA
VFLOAT
Float Voltage
4.158V
4.2V
4.242V
ITRIKL
Trickle Charge Current
20mA
5mA
50mA
10mA
70mA
15mA
VTRIKL
Trickle Charge Threshold
2.8V
2.9V
3V
VTRIKL, HYS
Trickle Charge Hysteresis
60mV
100mV
150mV
VUVLO
UVLO Threshold
3.7V
3.9V
4.1V
VUVLO, HYS
UVLO Hysteresis
150mV
200mV
300mV
VOVP
Input Over-Voltage Protect Threshold
6.8V
7V
7.2V
VOVP, HYS
Input Over-Voltage Protect Hysteresis
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
RPROG =2kΩ
RPROG =10kΩ
0.93V
0.93V
0
90µA
-2µA
RPROG =2kΩ
RPROG =10kΩ
2µA
0
3V
25µA
50µA
0
2µA
25µA
50µA
200mV
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
5
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
VMSD, RISE
Manual Shutdown Threshold, PROG
rising
1.15V
1.21V
1.3V
VMSD, FALL
Manual Shutdown Threshold, PROG
falling
0.95V
1.0V
1.05V
VASD, RISE
Automatic Shutdown Threshold, BAT
rising
5mV
30mV
50mV
VASD, FALL
Automatic Shutdown Threshold, BAT
falling
70mV
100mV
140mV
ITERM
C/10 Termination Current Threshold
85mV
100mV
115mV
VRECHRG
Auto Recharge Battery Voltage
4V
4.05V
4.1V
ICHRGb
CHRGb Pin Weak Pull-down Current
8µA
12µA
35µA
VCHRGb
CHRGb Pin Output Low Voltage
0.35V
0.6V
TLIM
Junction Temperature In Constant
Temperature Mode
120°C
RON
Power FET ON Resistance
600mΩ
TSS
Soft-Start Time
TRECHRG
Recharge Comparator Filter Time
0.75ms
2ms
4.5ms
TTERM
Termination Comparator Filter Time
0.4ms
1ms
2.5ms
IPROG
PROG Pin Pull-up Current
50µs
RPROG =2kΩ
3µA
Note 5: 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization.
Note 6: Supply current includes PROG pin current (approximately 100µA) but does not include any current delivered to the battery
through the BAT pin (approximately 100mA).
Typical Performance Characteristics
PROG Pin Voltage vs
Temperature
PROG Pin Voltage vs Supply
Voltage (Constant Current Mode)
VCC=5V
VBAT=4V
TA=25°C
RPROG=10K
1.0175
1.0150
VCC=5V
VBAT=4V
RPROG=10K
500
IBAT(mA)
1.0125
300
1.0100
1.000
1.0075
200
1.0050
0.995
100
1.0025
0.990
4.0
4.5
5.0
5.5
VCC(V)
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
VCC=5V
TA=25°C
RPROG=2K
400
VPROG(V)
VPROG(V)
600
1.0200
1.010
1.005
Charge Current vs
PROG Pin Voltage
6.0
6.5
7.0
1.0000
-50
-25
0
25
50
TEMPERATURE(°C)
75
100
0
0.00
0.25
0.50
0.75
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
1.00
1.25
VPROG(V)
6
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Typical Performance Characteristics
PROG Pin Pull-Up Current vs
Temperature and Supply Voltage
PROG Pin Current vs PROG Pin
Voltage (Clamp Current)
PROG Pin Current vs PROG Pin
Voltage (Pull-Up Current)
4.5
0
4.0
VBAT=4.3V
VPROG=0V
4.2
3.5
-50
3.0
-100
IPROG(µΑ)
IPROG(µA)
3.9
3.6
IPROG(µΑ)
2.5
-150
2.0
VCC=4.2V
VCC=6.5V
1.5
3.3
-200
VCC=5V
VBAT=4.3V
TA=25°C
1.0
3.0
0.5
2.7
-50
-25
0
25
50
75
100
125
TEMPERATURE(°C)
0.0
2.0
2.2
2.3
2.4
2.5
-300
2.0
2.6
4.17
4.15
200
300
400
500
600
4.210
4.205
VFLOAT(V)
VFLOAT(V)
4.19
4.200
4.190
4.190
4.185
-50
-25
IBAT(mA)
0
25
50
TEMPERATURE(°C)
75
40
38
20
15
5
0
1
2
3
4
VCHRGb(V)
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
5
6
6.5
7.0
CHRGb Pin I-V Curve
(Weak Pull-Down State)
15
10
30
28
22
7
6.0
20
32
24
0
5.5
34
26
VCC=5V
VBAT=4V
TA=25°C
10
5.0
ICHRGb(µA)
ICHRGb(mA)
ICHRGb(mA)
25
4.5
VCC(V)
36
30
5.5
TA=25°C
RPROG=10K
4.185
4.0
100
CHRGb Pin Current vs Temperature
(Strong Pull-Down State)
35
5.0
4.200
4.195
40
4.5
4.205
4.195
CHRGb Pin I-V Curve
(Strong Pull-Down State)
4.0
4.215
VCC=5V
RPROG=10K
4.210
4.21
100
3.5
Regulated Output (Float) Voltage
vs Supply Voltage
4.215
VCC=5V
TA=25°C
RPROG=1.25K
0
3.0
VPROG(V)
Regulated Output (Float) Voltage
vs Temperature
4.25
4.23
2.5
VPROG(V)
Regulated Output (Float) Voltage
vs Charge Current
VFLOAT(V)
2.1
VCC=5V
VBAT=4.3V
TA=25°C
-250
20
-50
5
VCC=5V
VBAT=4V
VCHRGb=1V
VCC=5V
VBAT=4.3V
TA=25°C
0
-25
0
25
50
75
TEMPERATURE(°C)
100
125
0
1
2
3
4
5
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
6
7
VCHRGb(V)
7
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Typical Performance Characteristics
CHRGb Pin Current vs Temperature
(Weak Pull-Down State)
25
Trickle Charge Current vs
Supply Voltage
Trickle Charge Current
vs Temperature
60
60
VCC=5V
VBAT=4.3V
VCHRGb=5V
20
RPROG=2K
50
40
ITRIKL(mA)
ICHRGb(µΑ)
ITRIKL(mA)
40
15
RPROG=2K
50
VCC=5V
VBAT=2.5V
30
VBAT=2.5V
TA=25°C
30
20
20
10
10
10
RPROG=10K
5
-50
-25
0
25
50
75
100
0
-50
125
TEMPERATURE(°C)
Trickle Charge Threshold vs
Temperature
0
25
50
75
TEMPERATURE(°C)
100
125
4.5
5.0
5.5
6.0
6.5
7.0
VCC(V)
Charge Current vs Battery Voltage
3.000
Charge Current vs Supply Voltage
600
600
500
500
400
400
RPROG=2K
VCC=5V
RPROG=10K
2.975
-25
RPROG=10K
0
4.0
2.925
IBAT(mA)
VTRIKL(V)
IBAT(mA)
2.950
300
2.900
2.875
200
200
VCC=5V
RPROG=2K
TA=25°C
2.850
100
2.825
2.800
-50
-25
0
25
50
75
100
0
2.7
125
TEMPERATURE(°C)
Charge Current vs Ambient
Temperature
4.09
RPROG=2K
3.6
VBAT(V)
3.9
4.2
4.5
VCC=5V
RPROG=10K
650
RDS(ON)(mΩ)
VRECHRG(V)
4.03
100
4.01
0
25
50
100 125 150
TEMPERATURE(°C)
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
75
3.99
-50
6.0
6.5
7.0
100
125
VCC=4.2V
IBAT=100mA
RPROG=2K
500
450
400
RPROG=10K
0
-50 -25
5.5
VCC(V)
550
4.05
200
5.0
700
600
VCC=5V
VBAT=4V
4.5
Power FET "ON" Resistance
vs Temperature
4.07
400
IBAT(mA)
3.3
RPROG=10K
0
4.0
4.11
500
300
3.0
100
Recharge Voltage Threshold
vs Temperature
600
VBAT=4V
TA=25°C
300
-25
0
25
50
75
TEMPERATURE(°C)
100
125
350
-50
-25
0
25
50
75
TEMPERATURE(°C)
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
8
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Operation
The BL4054/BL4054B is a single cell
Lithium-Ion battery charger using a constant
current / constant voltage algorithm. It can
deliver up to 800mA of charge current
(using a good thermal PCB layout) with a
final float voltage accuracy of 1%. The
BL4054/BL4054B includes an internal
P-channel power MOSFET and thermal
regulation circuitry. No blocking diode or
external current sense resistor is required;
thus, the basic charger circuit requires only
two external components. Furthermore, the
BL4054/BL4054B is capable of operating
from a USB power source.
A charge cycle begins when the voltage at
the VCC pin rises above the UVLO threshold
level and a 1% program resistor is
connected from the PROG pin to ground or
when a battery is connected to the charger
output. If the BAT pin is less than 2.9V, the
charger enters trickle charge mode. In this
mode, the BL4054/BL4054B supplies
approximately 1/10 the programmed charge
current to bring the battery voltage up to a
safe level for full current charging.
When the BAT pin voltage rises above 2.9V,
the charger enters constant-current mode,
where the programmed charge current is
supplied to the battery. If the battery voltage
is above 2.9V at power-on, BL4054B enters
the constant-current mode immediately,
while BL4054 will perform one more check.
If the battery voltage is below the
auto-recharge threshold, BL4054 enters the
constant current mode, otherwise it goes to
standby mode. This is the only difference
between the BL4054 and BL4054B. Refer
to Figure 1a and 1b for more details.
BL4054/BL4054B Rev 1.4
5/2009
Programming Charge Current
The charge current is programmed using a
single resistor from the PROG pin to ground.
The battery charge current is 1000 times
the current out of the PROG pin. The
program resistor and the charge current are
calculated using the following equations:
R PROG =
Normal Charge Cycle
PPMIC BU
When the BAT pin approaches the final float
voltage (4.2V), the BL4054/BL4054B enters
constant-voltage mode and the charge
current begins to decrease. When the
charge current drops to 1/10 of the
programmed value, the charge cycle ends.
1000V
I CHG
I CHG =
1000V
R PROG
The charge current out of the BAT pin can
be determined at any time by monitoring the
PROG pin voltage using the following
equation:
I BAT =
VPROG
• 1000
R PROG
Charge Termination
A charge cycle is terminated when the
charge current falls to 1/10 the programmed
value after the final float voltage is reached.
This condition is detected by using an
internal, filtered comparator to monitor the
PROG pin. When the PROG pin voltage
falls below 100mV for longer than TTERM
(typically 1ms), charging is terminated. The
charge current is latched off and the
BL4054/BL4054B enters standby mode,
where the input supply current drops to
100µA. (Note: C/10 termination is disabled
in trickle charging mode).
When charging, transient loads on the BAT
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
9
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
pin can cause the PROG pin to fall below
100mV for short periods of time before the
DC charge current has dropped to 1/10 the
programmed value. The 1ms filter time
(TTERM) on the termination comparator
ensures that transient loads of this nature
do not result in premature charge cycle
termination. Once the average charge
current drops below 1/10 the programmed
value, the BL4054/BL4054B terminates the
charge cycle and ceases to provide any
current through the BAT pin. In this state, all
loads on the BAT pin must be supplied by
the battery.
The BL4054 constantly monitors the BAT
pin voltage in standby mode. If this voltage
drops below the 4.05V recharge threshold
(VRECHRG), another charge cycle begins and
current is once again supplied to the battery.
To manually restart a charge cycle when in
standby mode, the input voltage must be
removed and reapplied, or the charger must
be shut down and restarted using the
PROG pin. Figure 1a and 1b shows the
state diagram of a typical charge cycle.
POWER ON
BAT < 2.9V
PROG
RECONNECTED
OR
UVLO CONDITION
STOPS
1/10 FULL CURRENT
CHRGb:STRONG
PULL-DOWN
BAT > 2.9V
2.9V<BAT<4.05V
ICC DROPS TO <25uA
CHRGb:Hi-Z IN UVLO
WEAK PULL-DOWN
OTHERWISE
PROG FLOATED
OR
UVLO CONDITION
FULL CURRENT
CHRGb:STRONG
PULL-DOWN
PROG < 100mV
NO CHARGE CURRENT
CHRGb:WEAK
PULL-DOWN
POWER ON
BAT < 2.9V
PROG
RECONNECTED
OR
UVLO CONDITION
STOPS
1/10 FULL CURRENT
CHRGb:STRONG
PULL-DOWN
BAT > 2.9V
2.9V<BAT<4.05V
ICC DROPS TO <25uA
CHRGb:Hi-Z IN UVLO
WEAK PULL-DOWN
OTHERWISE
PROG FLOATED
OR
UVLO CONDITION
FULL CURRENT
CHRGb:STRONG
PULL-DOWN
PROG < 100mV
NO CHARGE CURRENT
CHRGb:WEAK
PULL-DOWN
2.9V < BAT < 4.05V
Figure1b. State Diagram of BL4054B Charge Cycle
Charge Status Indicator (CHRGb)
The charge status output has three different
states: strong pull-down (~10mA), weak
pull-down (~12µA) and high impedance.
The strong pull-down state indicates that
the BL4054/BL4054B is in a charge cycle.
Once the charge cycle has terminated, the
pin state is determined by under-voltage
lockout conditions. A weak pull-down
indicates that VCC meets the UVLO
conditions and the BL4054/BL4054B is
ready to charge. High impedance indicates
that the BL4054/BL4054B is in under
voltage lockout mode: either VCC is less
than 100mV above the BAT pin voltage or
insufficient voltage is applied to the VCC pin.
A microprocessor can be used to
distinguish between these three states—the
application circuit of this method is shown in
the Typical Applications section.
2.9V < BAT < 4.05V
Manual Shutdown
BAT > 4.05V
Figure1a. State Diagram of BL4054 Charge Cycle
At any point in the charge cycle, the
BL4054/BL4054B can be put into shutdown
mode by removing RPROG thus floating the
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
10
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
PROG pin. This reduces the battery drain
current to less than 2µA and the supply
current to less than 50µA. A new charge
cycle can be initiated by reconnecting the
program resistor.
In manual shutdown, the CHRGb pin is in a
weak pull-down state as long as VCC is high
enough to exceed the UVLO conditions.
The CHRGb pin is in a high impedance
state if the BL4054/BL4054B is in under
voltage lockout mode: either VCC is within
100mV of the BAT pin voltage or insufficient
voltage is applied to the VCC pin.
Over-Voltage Protect
The BL4054/BL4054B has an internal
Over-Voltage Protect comparator, once the
input voltage VCC rises above 7V (VOVP), this
comparator will shut down the chip. This
feature can prevent the BL4054/BL4054B
from the over-voltage stress due to the input
transient at hot plug in. In this state, the
CHRGb pin will be high impedance. Once
the VCC falls back to safe range (VOVP - VOVP,
HYS), normal operation continues.
Automatic Recharge
Once the charge cycle is terminated, the
BL4054/BL4054B continuously monitors the
voltage on the BAT pin using a comparator
with a 2ms filter time (TRECHRG). A charge
cycle restarts when the battery voltage falls
below 4.05V (which corresponds to
approximately 80% to 90% battery capacity).
This ensures that the battery is kept at or
near a fully charged condition and
eliminates the need for periodic charge
cycle initiations. CHRGb output enters a
strong pull-down state during recharge
cycles.
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
Applications Information
Stability Considerations
The constant-voltage mode feedback loop
is stable without an output capacitor
provided a battery is connected to the
charger output. With no battery present, an
output capacitor is recommended to reduce
ripple voltage. When using high value, low
ESR ceramic capacitors, it is recommended
to add a 1Ω resistor in series with the
capacitor. No series resistor is needed if
tantalum capacitors are used.
In constant-current mode, the PROG pin is
in the feedback loop, not the battery. The
constant-current mode stability is affected
by the impedance at the PROG pin. With no
additional capacitance on the PROG pin,
the charger is stable with program resistor
values as high as 20k. However, additional
capacitance on this node reduces the
maximum allowed program resistor thus it
should be avoided.
Average, rather than instantaneous, charge
current may be of interest to the user. For
example, if a switching power supply
operating in low current mode is connected
in parallel with the battery, the average
current being pulled out of the BAT pin is
typically of more interest than the
instantaneous current pulses. In such a
case, a simple RC filter can be used on the
PROG pin to measure the average battery
current as shown in Figure 2. A 10k resistor
has been added between the PROG pin
and the filter capacitor to ensure stability.
Thermal Limiting
An internal thermal feedback loop reduces
the programmed charge current if the die
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
11
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
temperature attempts to rise above a preset
value of approximately 120°C. This feature
protects
the
BL4054/BL4054B
from
excessive temperature and allows the user
to push the limits of the power handling
capability of a given circuit board without
risk of damaging the BL4054/BL4054B. The
charge current can be set according to
typical
(not
worst-case)
ambient
temperature with the assurance that the
charger will automatically reduce the
current in worst-case conditions.
10k
CHARGE
CURRENT
MONITOR
CIRCUITRY
PROG
BL4054
RPROG
CFILTER
GND
from a 5V USB supply is programmed to
supply 400mA full-scale current to a
discharged Li-Ion battery with a voltage of
3.75V. Assuming θJA is 150°C/W, the
ambient temperature at which the
BL4054/BL4054B will begin to reduce the
charge current is approximately:
TA = 120°C − (5V − 3.75V) • 400mA • 150°C / W
TA = 45°C
The BL4054/BL4054B can be used above
45°C ambient, but the charge current will be
reduced from 400mA. The approximate
current at a given ambient temperature can
be approximated by:
I BAT =
Figure 2. Isolating Capacitive Load on PROG Pin
Power Dissipation
The
conditions
that
cause
the
BL4054/BL4054B to reduce charge current
through thermal feedback can be
approximated by considering the power
dissipated in the IC. Nearly all of this power
dissipation is generated by the internal
MOSFET—this is calculated to be
approximately:
PD = (VCC − VBAT ) • I BAT
where PD is the power dissipated, VCC is the
input supply voltage, VBAT is the battery
voltage and IBAT is the charge current. The
approximate ambient temperature at which
the thermal feedback begins to protect the
IC is:
TA = 120°C − PD • θ JA
TA = 120°C − (VCC − VBAT ) • I BAT • θ JA
Example: An BL4054/BL4054B operating
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
120°C − TA
(VCC − VBAT ) • θ JA
Using the previous example with an
ambient temperature of 60°C, the charge
current will be reduced to approximately:
IBAT =
120°C − 60°C
= 320mA
(5V − 3.75V) • 150°C / W
Moreover, when thermal feedback reduces
the charge current, the voltage at the PROG
pin is also reduced proportionally as
discussed in the Operation section.
It is important to remember that
BL4054/BL4054B applications do not need
to be designed for worst-case thermal
conditions since the IC will automatically
reduce power dissipation when the junction
temperature reaches approximately 120°C.
Thermal Considerations
Because of the small size of the ThinSOT
package, it is very important to use a good
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
12
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
thermal PC board layout to maximize the
available charge current. The thermal path
for the heat generated by the IC is from the
die to the copper lead frame, through the
package leads, (especially the ground lead)
to the PC board copper. The PC board
copper is the heat sink. The footprint copper
pads should be as wide as possible and
expand out to larger copper areas to spread
and dissipate the heat to the surrounding
ambient. Feed-through vias to inner or
backside copper layers are also useful in
improving the overall thermal performance
of the charger. Other heat sources on the
board, not related to the charger, must also
be considered when designing a PC board
layout because they will affect overall
temperature rise and the maximum charge
current.
The following table lists thermal resistance
for several different board sizes and copper
areas.
All measurements were taken in still air on
3/32" FR-4 board with the device mounted
on topside.
Table 1. Measured Thermal Resistance (2-Layer Board*)
COPPER AREA
TOPSIDE
BACKSIDE
BOARD
AREA
THERMAL RESISTANCE
JUNCTION-TO-AMBIENT
2500mm2
2500mm2
2500mm2
125℃/W
2
2500mm
2
2500mm2
125℃/W
2500mm
2
2
130℃/W
2500mm2
2500mm2
135℃/W
2
2
150℃/W
1000mm
225mm
2
100mm2
50mm
2
2500mm
2500mm
2500mm
Table 2. Measured Thermal Resistance (4-Layer Board**)
COPPER AREA
(EACH SIDE)
BOARD
AREA
THERMAL RESISTANCE
JUNCTION-TO-AMBIENT
2500mm2***
2500mm2
80℃/W
**Top and bottom layers use two ounce copper, inner layers use
one ounce copper
***10,000mm2 total copper area
VCC Bypass Capacitor
Many types of capacitors can be used for
input bypassing, however, caution must be
exercised when using multilayer ceramic
capacitors. Because of the self-resonant
and high Q characteristics of some types of
ceramic capacitors, high voltage transients
can be generated under some start-up
conditions, such as connecting the charger
input to a live power source. Adding a
1 Ω resistor in series with an X5R ceramic
capacitor will minimize start-up voltage
transients.
Charge Current Soft-Start
The BL4054/BL4054B includes a soft-start
circuit to minimize the inrush current at the
start of a charge cycle. When a charge
cycle is initiated, the charge current ramps
from zero to the full-scale current over a
period of approximately 50µs. This has the
effect of minimizing the transient current
load on the power supply during start-up.
*
Each layer uses one ounce copper
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
13
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Typical Applications
USB/
USB/Wall Adapter Power LiLi-Ion Charger
5V WALL
ADAPTER
BAT
USB
POWER
1k
VIN=5V
IBAT
3
BL4054
BL4054B
4
VCC
5
PROG
GND
2
1uF
10k
Full Featured Single Cell LiLi-Ion Charger
Li-Ion
CELL
2.5k
100mA/
500mA
uC
330Ω
4
VCC
3
BAT
BL4054
BL4054B
1
5
CHRGb
PROG
GND
2
1uF
500mA
Li-Ion
CELL
2k
SHDN
Basic LiLi-Ion Charger
with Reverse Polarity Input Protection
Using a Microprocessor to Determine CHRGb State
VDD
V+
4
5V WALL
ADAPTER
VCC
BL4054
BL4054B
1uF
2k
OUT
CHRGb
BAT
3
500mA
BL4054
BL4054B
uPROCESSOR
800k
VCC
PROG
GND
2
5
Li-Ion
CELL
2k
IN
800mA
800mA LiLi-Ion Charger
with External Power Dissipation
VIN=5V
0.25Ω
4
1uF
800mA
VCC
BAT
3
BL4054
BL4054B
5
PROG
GND
2
1.25k
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
Li-Ion
CELL
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
14
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Package Description
TSOT-23-5 Surface Mount Package
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
15
BL4054/BL4054B
800mA Standalone Linear Li-Ion Battery Charger
with Thermal Regulation in SOT23-5/TSOT23-5
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.889
1.295
0.035
0.051
A1
0.000
0.152
0.000
0.006
B
1.397
1.803
0.055
0.071
b
0.356
0.559
0.014
0.022
C
2.591
2.997
0.102
0.118
D
2.692
3.099
0.106
0.122
e
0.838
1.041
0.033
0.041
H
0.080
0.254
0.003
0.010
L
0.300
0.610
0.012
0.024
SOT-23-5 Surface Mount Package
PPMIC BU
BL4054/BL4054B Rev 1.4
5/2009
www.belling.com.cn
Belling Proprietary Information. Unauthorized Photocopy and Duplication Prohibited
©2009 Belling All Rights Reserved
16