TP4054 Standalone Linear Li-lon Battery Charger with Thermal
CHRG
Regulation in SOT
DESCRIPTION
The TP4054 is a complete constant-current/constant-voltage linear charger for single cell
lithium-ion batteries. Its SOT package and low external component count make the TP4054
ideally suited for portable applications. Furthermore, the TP4054 can work within USB and wall
adapter.
No external sense resistor is needed, and no blocking diode is required due to the internal
PMOSFET architecture and have prevent to negative Charge Current Circuit. 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 TP4054 automatically terminates the charge
cycle when the charge current drops to 1/10th the programmed value after the final float voltage is
reached.
When the input supply (wall adapter or USB supply) is removed, the TP4054 automatically enters
a low current state, dropping the battery drain current to less than 2uA. The TP4054 can be put
into shut down mode, reducing the supply current to 45uA. Other features include current monitor,
under voltage lockout, automatic recharge and a status pin to indicate charge termination and the
presence of an input voltage.
FEATURES
· Programmable Charge Current Up to
800mA
·No MOSFET, Sense Resistor or Blocking
Diode Required
· Complete Linear Charger in SOT23-5
Package for Single Cell Lithium-Ion
Batteries
·Constant-Current/Constant-Voltage
Operation with Thermal Regulation to
Maximize Charge Rate Without Risk of
Overheating
·Charges Single Cell Li-Ion Batteries Directly
from USB Port
·Preset 4.2V Charge Voltage with 1%
Accuracy
·Charge Current Monitor Output for Gas
Gauging
·Automatic Recharge
·Charge Status Output Pin
·C/10 Charge Termination
·45uA Supply Current in Shutdown
·2.9V Trickle Charge Threshold (TP4054)
·Soft-Start Limits Inrush Current
·Available in 5-Lead SOT-23 Package
APPLICATIONS
·Cellular Telephones, PDAs, MP3 Players
·Charging Docks and Cradles
·Blue tooth Applications
TYPICAL APPLICATION
600mA Single Cell Li-lon Charger
Complete Charge Cycle (650mAh Battery)
ABSOLUTE MAXIMUM RATINGS
·Input Supply Voltage(VCC)：-0.3V～10V
·PROG：-0.3V～VCC+0.3V
·BAT：-0.3V～7V
·
·BAT Short-Circuit Duration：Continuous
·BAT Pin Current：800mA
·PROG Pin Current：800uA
·Maximum Junction Temperature：145℃
·Operating Ambient Temperature Range：-40
·Storage Temp. Range：-65℃～125℃
·Lead Temp.(Soldering, 10sec)：260℃
：-0.3V～10V
℃～85℃
2
PACKAGE/ORDER INFORMATION
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ORDER PART NUMBER
TP4054-42-SOT25-R
S5 PART MARKING
S5 PACKAGE
5-LEAD PLASTIC SOT-23-5
54b
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature range, otherwise
specifications are at TA=25℃℃℃℃，，，，V
SYMBOL PARAMETER CONDITIONS MIN TYP MAX
V
CC
ICC
V
FLOAL
I
BAT
I
TRIKL
V
TRIKL
V
TRHYS
VUV
V
UVHYS
V
MSD
V
ASD
I
TERM
V
PROG
Input Supply Voltage
Input Supply Current
Regulated Output (Float)
Voltage
BAT Pin Current R
Trickle Charge Current V
Trickle Charge Threshold
Voltage
Trickle Charge Hysteresis
Voltage
V
Threshold
V
Hysteresis
Undervoltage Lockout
CC
Undervoltage Lockout
CC
Manual Shutdown
Threshold Voltage
VCC-V
Lockout
BAT
Threshold Voltage
C/10 Termination Current
Threshold
PROG Pin Voltage R
Pin Weak
Pull-Down Current
Pin Output Low
Voltage
=5V，unless otherwise noted.
CC
Charge Mode, R
PROG
= 10k
StandbyMode(Charge
Terminated)
Shutdown Mode (R
Connected,
VUV)
0℃≤TA≤85℃，I
PROG
R
PROG
Standby Mode, V
Shutdown Mode (R
Connected)
Sleep Mode,
BAT<VTRIKL
R
PROG
R
PROG
Not
PROG
V
< V
BAT
BAT
, or V
=40mA
CC
= 10k, Current Mode
= 1.66k, Current Mode
= 4.2V
BAT
Not
PROG
= 0V
, R
=10K, V
V
CC
PROG
BAT
=10K
Rising
=10K
From VCC Low to High
PROG Pin Rising
PROG Pin Falling
VCC from Low to High
VCC from High to Low
R
=10K
PROG
R
=2K
PROG
=10K，Current Mode
PROG
=5V
=5mA
UNI
TS
4.0 5 9.0 V
150
45
45
45
<
CC
4.158 4.2 4.242 V
90
250
0
100
400
－2.5
±1
－1
15 25 35 mA
2.8 2.9 3.0 V
60 80 100 mV
3.4 3.6 3.8 V
150 200 300 mV
3.40
1.90
3.50
2.00
60 5 100
30
8
40
10
50
0.9 1.0 1.1 V
8 20 35 µA
0.1 0.3 0.5 V
500
100
100
µA
µA
µA
100
110
450
－6
±2
－2
mA
mA
µA
µA
µA
3.60
2.10 V V
140
50
12
60
mV
mV
mA
mA
3
ΔV
CHRG
CHRG
CHRG
T
LIM
RECHRG
Recharge Battery
Threshold Voltage
Junction Temperature in
Constant Temperature
V
FLOAT-VRECHRG
Mode
RON
Power FET “ON”
Resistance
(Between VCC and BAT)
tss Soft-Start Time I
t
RECHARGE
t
TERM
I
PROG
Recharge Comparator
Filter Time
Termination Comparator
Filter Time
PROG Pin Pull-Up
Current
= 0 to I
BAT
V
High to Low
BAT
I
Falling Below I
BAT
=1000V/R
BAT
CHG
/10
TYPICAL PERFORRMANCE CHARACTERISTICS
PROG Pin Voltage vs Supply PROG Pin Voltage vs Charge Current vs
Voltage (Constant Current Mode) Temperature PROG Pin Voltage
PROG
100 150 200 mV
120 ℃
650 mΩ
20 µs
0.8 1.8 4 ms
0.8 1.8 4 ms
2.5 µA
Regulated Output(Float) Voltage Regulated Output(Float) Voltage Regulated Output(Float) Voltage
vs Charge Current vs Temperature vs Supply Voltage
Pin I-V Curve
Pin Current vs Temperature
Pin I-V Curve
(Strong Pull-Down State) (Strong Pull-Down State) (Weak Pull-Down State)
4
CHRG
Pin Current vs Temperature Trickle Charge Current vs Trickle Charge Current vs
(Weak Pull-Down State) Temperature Supply Voltage
Trickle Charge Threshold vs Charge Current vs Battery Charge Current vs Supply
Temperature Voltage Voltage
Charge Current vs Ambient Recharge Voltage vs power TEF “ON” Resistance
Temperature Temperature vs Temperature
5
PIN FUNCTIONS
（（（（Pin 1））））：Open-Drain Charge Status
Output. When the battery is charging, the
pin is pulled low by an internal
N-channel MOSFET. When the charge cycle
is completed, a weak pull-down of
approximately 20µA is connected to the
pin, indicating an “AC present” condition.
When the TP4054 detects an under voltage
lockout condition,
is forced high
impedance.
GND（（（（Pin 2））））：Ground
BAT（（（（Pin 3））））：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.
VCC（（（（Pin 4））））：Positive Input Supply Voltage.
Provides power to the charger. VCC can range
from 4V to 9V and should be bypassed with at
least a 1µF capacitor. When VCC drops to within
30mV
of the BAT pin voltage, theTP4054 enters
shutdown mode, dropping I
to less than 2µA
BAT
PROG（（（（Pin 5））））：Charge Current Program,
Charge Current Monitor and Shutdown Pin.
The charge current is programmed by
connecting a 1% resistor, R
,to ground.
PROG
When charging in constant-current mode,
this pin servos to 1V.
The PROG pin can also be used to shut down
the charger. Disconnecting the program resistor
from ground allows a 2.5µA current to pull the
PROG pin high. When it reaches the 2.70V
shutdown threshold voltage, the charger enters
shutdown mode, charging stops and the input
supply current. drops to 45µA. Reconnecting
R
to ground will return the charger to
PROG
normal operation.
BLOCK DIAGRAM
6
OPERATION
PROG BAT
1000
BAT
I
1.2 0.4 1666
10000
Formula 2：
R
= （I
PROG
The TP4054 is a single cell lithium-lion battery
charger using a constant-current/constant-volt
-age algorithm. It can deliver up to 800mA of
Exp1:When we need I
1.
＝0.4A,user
BAT
charge current (using a good thermal PDB
layout) with a final float voltage accuracy of±1%.
The TP4054 includes an internal P-channel
R
1000 4
= × − × =
PROG
0.4 3
power MOSFET and thermal regulation
R
＝1.66kΩ
circuitry. No blocking diode or external current
sense resistor is required; thus, the basic
charger circuit requires only two external
components Furthermore, the TP4054 is
capable of operating from a USB power source.
Normal Charge Cycle
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 TP4054
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. When the BAT pin
approaches the final float voltage (4.2V), the
TP4054 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.
Programming Charge Current
The charge current is programmed using a
single resistor from the PROG pin to ground.
The program resistor and the charge current
are calculated using the following equations:
Formula 1：
PROG
Exp2:When we need I
2.
R
R
PROG
PROG
1000 1000
= = = （Ω）
I
BAT
＝10kΩ
Charge Termination
BAT
0.1
＝0.1A,user
A charge cycle is terminated when the charge
current falls to 1/10th 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 t
(typically 1.8ms), charging
TERM
is terminated. The charge current is latched off
and the TP4054 enters standby mode, where
the input supply current drops to 45µA. (Note:
C/10 termination is disabled in trickle charging
and thermal limiting modes).
When charging, transient loads on the BAT pin
can cause the PROG pin to fall below 100mV
for short periods of time before the DC charge
current has dropped to 1/10th the programmed
value. The 1.8ms filter time (t
termination comparator ensures that transient
loads of this nature do not result in premature
charge cycle termination. Once the average
charge current drops below 1/10th the
programmed value, the TP4054 terminates the
charge cycle and ceases to provide any current
through the BAT pin. In this state, all loads on
R I
I
BAT
1000 4
= × −
1.2
3
the BAT pin must be supplied by the battery.
The TP4054 constantly monitors the BAT pin
voltage in standby mode. If this voltage drops
（I
>0.15A）
BAT
below the 4.05V recharge threshold (V
another charge cycle begins and current is
once again supplied to the battery. To manually
7
≤0.15A）
BAT
Formula
（Ω）
Formula
) on the
TERM
RECHRG
),
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 1
shows the state diagram of a typical charge
cycle.
Charge Status Indicator (
)
The charge status output has three different
states: strong pull-down (~10mA), weak
pull-down (~20µA) and high impedance. The
strong pull-down state indicates that the
TP4054 is in a charge cycle. Once the charge
cycle has terminated, the pin state is
determined by undervoltage lockout conditions.
A weak pull-down indicates that VCC meets the
UVLO conditions and the TP4054 is ready to
charge. High impedance indicates that the
TP4054 is in undervoltage 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—this
method is discussed in the Applications
Information section.
Thermal Limiting
An internal thermal feedback loop reduces the
programmed charge current if the die
temperature attempts to rise above a preset
value of approximately 100℃. The charging will
be cut off untill the temperature is over
140℃.This feature protects the TP4054 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 TP4054. The charge current can be set
according to typical (not worst-case) ambient
temperature with the assurance that the
charger will automatically reduce thecurrent in
worst-case conditions. ThinSOT power
considerations are discussed further in the
Applications Information section.
above the undervoltage lockout threshold. The
UVLO circuit has a built-in hysteresis of 200mV.
Furthermore, to protect against reverse current
in the power MOSFET, theUVLO circuit keeps
the charger in shutdown mode if VCC falls to
within 30mV of the battery voltage. If the UVLO
comparator is tripped, the charger will not come
out of shutdown mode until VCC rises 100mV
above the battery voltage.
Manual Shutdown
At any point in the charge cycle, the TP4054
can be put into shutdown mode by removing
R
thus floating the PROG pin. This
PROG
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 CHRG pin is in a
weak pull-down state as long as VCC is high
enough to exceed the UVLO conditions. The
CHRG pin is in a high impedance state if the
TP4054 is in undervoltage lockout mode: either
VCC is within 100mV of the BAT pin voltage or
insufficient voltage is applied to the VCC pin.
Automatic Recharge
Once the charge cycle is terminated, the
TP4054 continuously monitors the voltage on
the BAT pin using a comparator with a 1.8ms
filter time (t
RECHARGE
). 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. CHRG output enters a
strong pulldown state during recharge cycles.
Undervoltage Lockout (UVLO)
An internal undervoltage lockout circuit
monitors the input voltage and keeps the
charger in shutdown mode until VCC rises
8
current may be of interest to the user. For
•−=
θ
−°=
θ
••−−°
=
θ
°••−−°=
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.
Figure 1. State Diagram of a Typical Charge
Cycle
Stability Considerations
Figure 2. Isolating Capacitive Load on PROG
Pin and Filtering
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.
Power Dissipation
The conditions that cause the TP4054 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:
In constant-current mode, the PROG pin is in
IVVP
)(
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
where PD is the power dissipated, VCC is the
input supply voltage, V
and I
is the charge current. The approximate
BAT
ambient temperature at which the thermal
feedback begins to protect the IC is:
120
PCT
maximum allowed program resistor. The pole
frequency at the PROG pin should be kept
above 100kHz. Therefore, if the PROG pin is
loaded with a capacitance, CPROG, the
following equation can be used to calculate the
maximum resistance value for R
PROG
≤
π
1
5
CR••
102
PROG
PROG
:
Average, rather than instantaneous, charge
Example: An TP4054 operating 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
150℃/W (see Board Layout Considerations),
the ambient temperature at which the TP4054
will begin to reduce the charge current is
approximately:
A
9
BATBATCCD
is the battery voltage
BAT
JADA
IVVCT
)(120
JABATBATCCA
is
JA
WCmAVVCT
/150)400()75.35(120
CCWCWCT
°−°=°•−°=
°
=
°
°−°
θ
°−°
A
CT
45
A
The TP4054 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:
75120/1505.0120
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.
120
=
I
BAT
Using the previous example with an ambient
temperature of 60°C, the charge current will be
reduced to approximately:
=
I
BAT
mAI
320
=
BAT
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 TP4054 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 approximately120℃.
Thermal Considerations
Because of the small size of the ThinSOT23-5
package, it is very important to use a good
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. Feedthrough 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
−°
TC
A
θ
•−
)(
VV
JABATCC
CC
60120
°•−
=
WCVV
/150)75.35(
60
C
AC
/5.187
°
Increasing Thermal Regulation
Current
Reducing the voltage drop across the internal
MOSFET can significantly decrease the power
dissipation in the IC. This has the effect of
increasing the current delivered to the battery
during thermal regulation. One method is by
dissipating some of the power through an
external component, such as a resistor or
diode.
Example: An TP4054 operating from a 5V wall
adapter is programmed to supply 800mA
full-scale current to a discharged Li-Ion battery
with a voltage of 3.75V. Assuming
125℃/W, the approximate charge current at
anambient temperature of 25°C is:
I
BAT
dropping voltage across a resistor in series with
a 5V wall adapter (shown in Figure 3), the
on-chip power dissipation can be decreased,
thus increasing the thermally regulated charge
current
is
JA
CC
= By
25120
WCVV
/125)75.35(
°•−
mA
608
=
10
I
°−°
θ
BAT
=
25120
CC
)(
VRIV
θ
•−−
JABATCCBATS
Figure 3. A Circuit to Maximize Thermal Mode
Charge Current
Solving for I
=
I
BAT
Using RCC = 0.25Ω, VS = 5V, V
25℃ and
thermally regulated charge current to be:
I
＝708.4mA
BAT
While this application delivers more energy to
the battery and reduces charge time in thermal
mode, it may actually lengthen charge time in
voltage mode if VCC becomes low enough to
put the TP4054 into dropout. Figure 4 shows
how this circuit can result in dropout as RCC
becomes large.
This technique works best when RCC values are
minimized to keep component size small and
avoid dropout. Remember to choose a resistor
with adequate power handling capability.
using the quadratic formula2.
BAT
2
−−−
VVVV
)()(
BATSBATS
R
2
CC
= 3.75V, TA =
BAT
= 125℃/W we can calculate the
JA
−°
θ
JA
TCR
)120(4
ACC
Figure 4. Charge Current vs R
CC
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 1.5Ω resistor in series with an X5R
ceramic capacitor will minimize start-up voltage
transients. For more information, refer to
Application Note 88.
Charge Current Soft-Start
The TP4054 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
20µs.
This has the effect of minimizing the transient
current load on the power supply during
start-up.
Status Output Pin
The
the input voltage is greater than the
undervoltage lockout threshold level. A weak
11
pin can provide an indication that
pull-down current of approximately 20mA
indicates that sufficient voltage is applied to
VCC to begin charging. When a discharged
battery is connected to the charger, the
constant current portion of the charge cycle
begins and the
pin can sink up to 10mA to drive an LED
that indicates that a charge cycle is in progress.
When the battery is nearing full charge, the
charger enters the constant-voltage portion of
the charge cycle and the charge current begins
to drop. When the charge current drops below
1/10 of the programmed current, the charge
cycle ends and the strong pull-down is replaced
by the 20mA pull-down, indicating that the
charge cycle has ended. If the input voltage is
removed or drops below the undervoltage
lockout threshold, the
impedance. Figure 5 shows that by using two
different value pull-up resistors, a
microprocessor can detect all three states from
this pin.
pin pulls to ground. The
pin becomes high
Figure 5. Using a Microprocessor to
Determine
To detect when the TP4054 is in charge mode,
force the digital output pin (OUT) high and
measure the voltage at the
N-channel MOSFET will pull the pin voltage low
even with the 2k pull-up resistor. Once the
charge cycle terminates, the N-channel
MOSFET is turned off and a 20mA current
source is connected to the
pin will then be pulled high by the 2k pull-up
resistor. To determine if there is a weak
pull-down current, the OUT pin should be
forced to a high impedance state. The weak
State
pin. The
pin. The IN
current source will pull the IN pin low through
the 800k resistor; if
the IN pin will be pulled high, indicating that the
part is in a UVLO state.
Reverse Polarity Input Voltage Protection:
In some applications, protection from reverse
polarity voltage on VCC is desired. If the supply
voltage is high enough, a series blocking diode
can be used. In other cases, where the voltage
drop must be kept low a P-channel MOSFET
can be used (as shown in Figure 6).
is high impedance,
Figure 6. Low Loss Input Reverse
Polarity Protection
USB and Wall Adapter Power:
The TP4054 allows charging from both a wall
adapter and a USB port. Figure 7 shows an
example of how to combine wall adapter and
USB power inputs. A P-channel MOSFET, MP1,
is used to prevent back conducting into the
USB port when a wall adapter is present and a
Schottky diode, D1, is used to prevent USB
power loss through the 1k pull-down resistor.
Typically a wall adapter can supply more
current than the 500mA-limited USB port.
Therefore, an N-channel MOSFET, MN1, and
an extra 10k program resistor are used to
increase the charge current to 600mA when the
wall adapter is present.
Figure 7.Combining Wall Adapter and
USB power
12
PACKAGE DESCRIPTION S5 Package
5-Lead Plastic TSOT-23-5
TYPICAL APPLICATIONS
13
Red Lingt And Green Light Control Circuit
14
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