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Final Electrical Specifications
LTC4054-4.2/LTC4054X-4.2 Standalone Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT
February 2003
FEATURES
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DESCRIPTIO
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Programmable Charge Current Up to 800mA No External MOSFET, Sense Resistor or Blocking Diode Required Complete Linear Charger in ThinSOTTM 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 25A Supply Current in Shutdown 2.9V Trickle Charge Threshold (LTC4054) Available Without Trickle Charge (LTC4054X) Soft-Start Limits Inrush Current
The LTC(R)4054 is a complete constant-current/constantvoltage linear charger for single cell lithium-ion batteries. Its ThinSOT package and low external component count make the LTC4054 especially well-suited for portable applications. Furthermore, the LTC4054 is specifically designed to work within USB power specifications. No external sense 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 LTC4054 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 LTC4054 automatically enters a low current state, dropping the battery drain current to less than 2A. The LTC4054 can be put into shutdown mode, reducing the supply current to 25A. Other features include charge current monitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and the presence of input voltage.
, LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation.
APPLICATIO S
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Cellular Telephones, PDAs Portable MP3 Players Charging Docks and Cradles Bluetooth Applications
TYPICAL APPLICATIO
VIN 4.5V TO 5.25V
Complete Charge Cycle (750mAh Battery)
700 600 CONSTANT CURRENT CONSTANT POWER CONSTANT VOLTAGE 4.75 4.50
600mA Single Cell Li-Ion Charger
CHARGE CURRENT (mA)
500 400 300 200 100 0 0
1F
4 VCC 3 BAT LTC4054-4.2 5 PROG GND 2
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600mA 4.2V Li-Ion BATTERY
1.65k
VCC = 5V JA = 130C/W RPROG = 1.65k TA = 25C
3.00 0.25 0.5 0.75 1.0 1.25 1.5 1.75 2.0 TIME (HOURS) 405442 TAO1b
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Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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BATTERY VOLTAGE (V)
4.25 4.00 3.75 3.50 CHARGE TERMINATED 3.25
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LTC4054-4.2/LTC4054X-4.2
ABSOLUTE
(Note 1)
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RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW CHRG 1 GND 2 BAT 3 4 VCC 5 PROG
Input Supply Voltage (VCC) ......................... -0.3 to 10V PROG ............................................. - 0.3V to VCC + 0.3V BAT, CHRG ................................................. -0.3V to 7V BAT Short-Circuit Duration .......................... Continuous BAT Pin Current ................................................. 800mA PROG Pin Current ................................................ 800A Maximum Junction Temperature .......................... 125C Operating Temperature Range (Note 2) .. - 40C to 85C Storage Temperature Range ................. - 65C to 125C Lead Temperature (Soldering, 10 sec).................. 300C
ORDER PART NUMBER LTC4054ES5-4.2 LTC4054XES5-4.2 S5 PART MARKING LTH7 LTADY
S5 PACKAGE 5-LEAD PLASTIC TSOT-23
TJMAX = 150C, (JA = 100C/ W TO 150C/W DEPENDING ON PC BOARD LAYOUT) (N0TE 4)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25C. VCC = 5V, unless otherwise noted.
SYMBOL VCC ICC PARAMETER Input Supply Voltage Input Supply Current Charge Mode (Note 3), RPROG = 2k Standby Mode (Charge Terminated) Shutdown Mode (RPROG Not Connected, VCC < VBAT, or VCC < VUV) 0C TA 85C, IBAT = 40mA RPROG = 10k, Current Mode RPROG = 2k, Current Mode Standby Mode, VBAT = 4.2V Shutdown Mode (RPROG Not Connected) Sleep Mode, VCC = 0V VBAT < 2.9V, RPROG = 2k (Note 6) RPROG = 2k, VBAT Rising (Note 6) RPROG = 2k (Note 6) From VCC Low to High PROG Pin Rising PROG Pin Falling VCC from Low to High VCC from High to Low RPROG = 10k (Note 5) RPROG = 2k RPROG = 10k, Current Mode VCHRG = 5V ICHRG = 5mA VFLOAT - VRECHRG 100
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ELECTRICAL CHARACTERISTICS
CONDITIONS
q q q q
MIN 4.25
TYP 1200 200 25
MAX 6.5 2000 500 50 4.242 107 535 -6 2 2 70 3.0 110 3.92 300 1.30 1.1 140 50 0.115 0.115 1.07 35 0.6 200
UNITS V A A A V mA mA A A A mA V mV V mV V V mV mV mA/mA mA/mA V A V mV
VFLOAT IBAT
Regulated Output (Float) Voltage BAT Pin Current
4.158 93 465 0
4.2 100 500 -2.5 1 1 45 2.9 80 3.8 250 1.21 1.0 100 30 0.10 0.10 1.0 20 0.35 150
ITRIKL VTRIKL VTRHYS VUV VUVHYS VMSD VASD ITERM VPROG ICHRG VCHRG VRECHRG
Trickle Charge Current Trickle Charge Threshold Trickle Charge Hysteresis VCC Undervoltage Lockout Threshold VCC Undervoltage Lockout Hysteresis Manual Shutdown Threshold VCC - VBAT Lockout Threshold C/10 Termination Current Threshold PROG Pin Voltage CHRG Pin Weak Pull-Down Current CHRG Pin Output Low Voltage Recharge Battery Threshold
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20 2.8 60 3.7 150 1.15 0.9 70 5 0.085 0.085 0.93 8
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LTC4054-4.2/LTC4054X-4.2
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25C. VCC = 5V, unless otherwise noted.
SYMBOL TLIM RON tSS tRECHARGE tTERM IPROG PARAMETER Junction Temperature in Constant Temperature Mode Power FET "ON" Resistance (Between VCC and BAT) Soft-Start Time Recharge Comparator Filter Time Termination Comparator Filter Time PROG Pin Pull-Up Current Current Mode IBAT = 0 to IBAT =1000V/RPROG VBAT High to Low IBAT Falling 0.75 400 CONDITIONS MIN TYP 120 600 100 2 1000 3 Note 3: Supply current includes PROG pin current but does not include any current delivered to the battery through the BAT pin. Note 4: See Thermal Considerations. Note 5: ITERM is expressed as a fraction of measured full charge current with indicated PROG resistor. Note 6: This parameter is not applicable to the LTC4054X. MAX UNITS C m s ms s A
ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: The LTC4054E-4.2 and the LTC4054XE-4.2 are guaranteed to meet performance specifications from 0C to 70C. Specifications over the -40C to 85C operating temperature range are assured by design, characterization and correlation with statistical process controls.
PI FU CTIO S
CHRG (Pin 1): Open-Drain Charge Status Output. When the battery is charging, the CHRG pin is pulled low by an internal N-channel MOSFET. When the charge cycle is completed, a weak pull-down of approximately 20A is connected to the CHRG pin, indicating an "AC present" condition. When the LTC4054 detects an undervoltage lockout condition, CHRG is forced to a high impedance state. 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 and is disconnected in shutdown mode. VCC (Pin 4): 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 1F capacitor. When VCC drops to within 30mV of the BAT pin voltage, the LTC4054 enters shutdown mode, dropping IBAT to less than 2A. PROG (Pin 5): Charge Current Program, Charge Current Monitor and Shutdown Pin. The charge current is programmed by connecting a 1% resistor, RPROG, 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 3A 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 25A. 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.
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LTC4054-4.2/LTC4054X-4.2
BLOCK DIAGRA
MA
CA
-
+
REF 1.21V
SHDN
C1
R3 1V R4
+
CHRG 1 STANDBY VCC TRICKLE CHARGE DISABLED ON LTC4054X C2
0.1V R5
-
3A C3
-
2.9V
+
TO BAT PROG 5 RPROG GND 2
4
+
-
-
+
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4 VCC 120C TA TDIE 1x 1000x BAT 5A R1 3
+
VA R2
-
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LTC4054-4.2/LTC4054X-4.2
OPERATIO
The LTC4054 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 LTC4054 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 three external components. Furthermore, the LTC4054 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. If the BAT pin is less than 2.9V, the charger enters trickle charge mode. In this mode, the LTC4054 supplies approximately 1/10 the programmed charge current to bring the battery voltage up to a safe level for full current charging. (Note: The LTC4054X does not include this trickle charge feature). 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 LTC4054 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 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:
1000V 1000V RPROG = , ICHRG = ICHRG RPROG
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The charge current out of the BAT pin can be determined at any time by monitoring the PROG pin voltage using the following equation:
IBAT =
VPROG * 1000 RPROG
Charge Termination The charge cycle terminates when the charge current falls to 1/10th the programmed current. An internal comparator senses when the PROG pin voltage falls below 100mV1 and puts the LTC4054 into standby mode. In standby mode, the LTC4054 ceases to provide charge current to the battery and the input supply current drops to 200A. If the battery voltage drops below 4.05V, a recharge cycle will begin. To manually restart the charge cycle, the input voltage must be removed and reapplied, or the charger must be shut down and restarted by momentarily floating the PROG pin. Charge Status Indicator (CHRG) The charge status output has three different states: strong pull-down (~10mA), weak pull-down (~20A) and high impedance. The strong pull-down state indicates that the LTC4054 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 LTC4054 is ready to charge. High impedance indicates that the LTC4054 is in undervoltage lockout mode: either VCC is within 100mV of 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.
Note 1: Any external sources that hold the PROG pin above 100mV will prevent the LTC4054 from terminating a charge cycle.
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LTC4054-4.2/LTC4054X-4.2
OPERATIO
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 120C. This feature protects the LTC4054 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 LTC4054. 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. ThinSOT power considerations are discussed further in the Applications Information section. Undervoltage Lockout (UVLO) An internal undervoltage lockout circuit monitors the input voltage and keeps the charger in shutdown mode until VCC rises 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, the UVLO 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 LTC4054 can be put into shutdown mode by removing RPROG thus floating the PROG pin. This reduces the battery drain current to less than 2A and the supply current to less than 50A. A new charge cycle can be initiated by reconnecting the program resistor.
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Automatic Recharge Once the charge cycle is terminated, the LTC4054 continuously monitors the voltage on the BAT pin. 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 conditon and eliminates the need for periodic charge cycle initiations. CHRG output enters a strong pulldown state during recharge cycles.
POWER ON BAT < 2.9V TRICKLE CHARGE MODE 1/10TH FULL CURRENT CHRG: STRONG PULL-DOWN BAT > 2.9V SHUTDOWN MODE ICC DROPS TO <30A CHRG: Hi-Z IN UVLO WEAK PULL-DOWN OTHERWISE CHARGE MODE FULL CURRENT CHRG: STRONG PULL-DOWN PROG < 100mV STANDBY MODE NO CHARGE CURRENT PROG FLOATED OR UVLO CONDITION CHRG: WEAK PULL-DOWN 2.9V < BAT < 4.05V
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PROG RECONNECTED OR UVLO CONDITION STOPS
BAT > 2.9V
Figure 1. State Diagram of a Typical Charge Cycle
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LTC4054-4.2/LTC4054X-4.2
APPLICATIO S I FOR ATIO
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 1 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. The pole frequency at the PROG pin should be kept above 100kHz. Therefore,
PROG LTC4054 GND
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Figure 2. Isolating Capacitive Load on PROG Pin and Filtering
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if the PROG pin is loaded with a capacitance, CPROG, the following equation can be used to calculate the maximum resistance value for RPROG: RPROG 1 2 * 105 * CPROG 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.
10k CHARGE CURRENT MONITOR CIRCUITRY CFILTER RPROG
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LTC4054-4.2/LTC4054X-4.2
APPLICATIO S I FOR ATIO
Power Dissipation
The conditions that cause the LTC4054 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) * IBAT 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 = 120C - PDJA TA = 120C - (VCC - VBAT) * IBAT * JA Example: An LTC4054 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 JA is 150C/W (see Board Layout Considerations), the ambient temperature at which the LTC4054 will begin to reduce the charge current is approximately: TA = 120C - (5V - 3.75V) * (400mA) * 150C/W TA = 120C - 0.5W * 150C/W = 120C - 75C TA = 45C The LTC4054 can be used above 45C ambient, but the charge current will be reduced from 400mA. The approximate current at a given ambient temperature can be approximated by:
IBAT 120C - TA = ( VCC - VBAT ) * JA
Using the previous example with an ambient temperature of 60C, the charge current will be reduced to approximately:
IBAT =
120C - 60C 60C = (5V - 3.75V) * 150C/W 187.5C/A
IBAT = 320mA
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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 LTC4054 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 120C. Thermal Considerations Because of the small size of the ThinSOT 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 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 one ounce copper.
Table 1. Measured Thermal Resistance
COPPER AREA TOPSIDE* BACKSIDE 2500mm2 1000mm2 225mm2 100mm2 50mm2 2500mm2 2500mm2 2500mm2 2500mm2 2500mm2 BOARD AREA 2500mm2 2500mm2 2500mm2 2500mm2 2500mm2 THERMAL RESISTANCE JUNCTION-TO-AMBIENT 125C/W 125C/W 130C/W 135C/W 150C/W *Device is mounted on topside
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LTC4054-4.2/LTC4054X-4.2
APPLICATIO S I FOR ATIO
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 LTC4054 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 JA is 125C/W, the approximate charge current at an ambient temperature of 25C is:
CHARGE CURRENT (mA)
IBAT =
120C - 25C = 608mA (5V - 3.75V)* 125C / W
By 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.
IBAT =
120C - 25C (VS - IBATRCC - VBAT )* JA
VS RCC
VCC BAT 1F LTC4054-4.2 PROG GND RPROG Li-Ion CELL
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Figure 3. A Circuit to Maximize Thermal Mode Charge Current
Solving for IBAT using the quadratic formula2. IBAT = 4R (120C - TA ) (VS - VBAT ) - (VS - VBAT )2 CC JA 2RCC
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Using RCC = 0.25, VS = 5V, VBAT = 3.75V, TA = 25C and JA = 125C/W we can calculate the thermally regulated charge current to be: IBAT = 708.4mA 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 LTC4054 into dropout. Figure 4 shows how this circuit can result in dropout as RCC becomes large.
1000 VS = 5V 800 CONSTANT CURRENT 600 VS = 5.5V 400 THERMAL MODE 200 VS = 5.25V DROPOUT 0 0 0.25 0.5 0.75 1.0 RCC () VBAT = 3.75V TA = 25C JA = 125C/W RPROG = 1.25k 1.25 1.5 1.75
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Figure 4. Charge Current vs RCC
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. 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 1.5 resistor in series with an X5R ceramic capacitor will minimize start-up voltage transients. For more information, refer to Application Note 88.
Note 2: Large values of RCC will result in no solution for IBAT. This indicates that the LTC4054 will not generate enough heat to require thermal regulation.
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LTC4054-4.2/LTC4054X-4.2
APPLICATIO S I FOR ATIO
Charge Current Soft-Start
The LTC4054 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 100s. This has the effect of minimizing the transient current load on the power supply during start-up. CHRG Status Output Pin With no battery present, the CHRG pin can provide an indication that the input voltage is present and it is greater than the undervoltage lockout threshold level. A weak pull-down current of approximately 20A 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 CHRG pin pulls to ground. The CHRG 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 20A pull-down, indicating that the charge cycle has ended. If the input voltage is removed or drops below the undervoltage lockout threshold, the CHRG pin becomes
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high impedance. Figure 5 shows that by using two different value pull-up resistors, a microprocessor can detect all three states from this pin. To detect when the LTC4054 is in charge mode, force the digital output pin (OUT) high and measure the voltage at the CHRG pin. 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 20A current source is connected to the CHRG pin. The IN 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 current source will pull the IN pin low through the 800k resistor; if CHRG is high impedance, the IN pin will be pulled high, indicating that the part is in a UVLO state.
V+ VDD VCC LTC4054 CHRG 800k 2k PROCESSOR OUT IN
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Figure 5. Using a Microprocessor to Determine CHRG State
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LTC4054-4.2/LTC4054X-4.2
PACKAGE DESCRIPTIO
0.62 MAX
0.95 REF
3.85 MAX 2.62 REF
RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR
0.20 BSC 1.00 MAX DATUM `A'
0.30 - 0.50 REF 0.09 - 0.20 (NOTE 3) NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193
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S5 Package 5-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1635)
2.90 BSC (NOTE 4) 1.22 REF 1.4 MIN 2.80 BSC 1.50 - 1.75 (NOTE 4) PIN ONE 0.30 - 0.45 TYP 5 PLCS (NOTE 3) 0.95 BSC 0.80 - 0.90 0.01 - 0.10 1.90 BSC
S5 TSOT-23 0302
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LTC4054-4.2/LTC4054X-4.2
TYPICAL APPLICATIO
Full Featured Single Cell Li-Ion Charger
VIN = 5V
4 VCC 330 1
BAT PROG
3 5
1F 500mA
1F
LTC4054-4.2 CHRG GND 2
+
2k SHDN
GND 2
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RELATED PARTS
PART NUMBER LT1571 LTC1729 LTC1730 LTC1731 LTC1732 LTC1733 LTC1734 LTC1734L LTC1998 LTC4050 DESCRIPTION 200kHz/500kHz Switching Battery Charger Lithium-Ion Battery Pulse Charger Lithium-Ion Linear Battery Charger Controller Lithium-Ion Linear Battery Charger Controller Monolithic Lithium-Ion Linear Battery Charger Lithium-Ion Linear Battery Charger in ThinSOT Lithium-Ion Linear Battery Charger in ThinSOT Lithium-Ion Low Battery Detector Lithium-Ion Linear Battery Charger Controller COMMENTS Up to 1.5A Charge Current; Preset and Adjustable Battery Voltages No Blocking Diode Required, Current Limit for Maximum Safety Simple Charger uses External FET, Features Preset Voltages, C/10 Charger Detection and Programmable Timer Simple Charger uses External FET, Features Preset Voltages, C/10 Charger Detection and Programmable Timer, Input Power Good Indication Standalone Charger with Programmable Timer, Up to 1.5A Charge Current Simple ThinSOT Charger, No Blocking Diode, No Sense Resistor Needed Accurate, Low Current Version of LTC1734 1% Accurate 2.5A Quiescent Current, SOT-23 Simple Charger uses External FET, Features Preset Voltages, C/10 Charger Detection and Programmable Timer, Input Power Good Indication, Thermistor Interface No Blocking Diode or External Power FET Required Standalone Charger with Programmable Timer, Up to 1.25A Charge Current For Simultaneous Operation of USB Peripheral and Battery Charging from USB Port, Keeps Current Drawn from USB Port Constant, Keeps Battery Fresh, Use with the LTC4053, LTC1733, or LTC4054 Lithium-Ion Battery Charger Termination Controllers Time or Charge Current Termination, Preconditioning 8-Lead MSOP
LTC4052 LTC4053 LTC4410
Monolithic Lithium-Ion Battery Pulse Charger USB Compatible Monolithic Li-Ion Battery Charger USB Power Manager
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Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 q FAX: (408) 434-0507
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800mA Li-Ion Charger with External Power Dissipation Basic Li-Ion Battery Charger with Reverse Polarity Input Protection
VIN = 5V 0.25 4 VCC BAT PROG 3 5 800mA LTC4054-4.2
5V WALL ADAPTER 1F 4 VCC BAT PROG 3 5 500mA LTC4054-4.2
+
+
1.25k
GND 2
2k
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405442i LT/TP 0203 1.5K * PRINTED IN USA
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 2003

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