Datasheet LTC4001 (Analog Devices) - 6
| Manufacturer | Analog Devices |
| Description | 2A Synchronous Buck Li-Ion Charger |
| Pages / Page | 20 / 6 — PI FU CTIO S. FAULT (Pin 10):. IDET (Pin 13):. NTC (Pin 11):. SS (Pin … |
| File Format / Size | PDF / 241 Kb |
| Document Language | English |
PI FU CTIO S. FAULT (Pin 10):. IDET (Pin 13):. NTC (Pin 11):. SS (Pin 14):. TIMER (Pin 15):. PROG (Pin 12):. BATSENS (Pin 16):
Model Line for this Datasheet
Text Version of Document
LTC4001
U U U PI FU CTIO S FAULT (Pin 10):
Battery Fault. This pin is a logic high if a
IDET (Pin 13):
Charge Rate Detection Threshold. Connect- shorted battery is detected or if a temperature fault is ing a resistor, RIDET to GNDSENS programs the charge detected. A temperature fault occurs with the temperature rate detection threshold. If RIDET = RPROG, CHRG provides monitor circuit enabled and the thermistor temperature is an IBAT/10 indication. For other thresholds see the Appli- either below 0°C or above 50°C (typical). cations Information section.
NTC (Pin 11):
Input to the NTC (Negative Temperature
SS (Pin 14):
Soft-Start/Compensation. Provides soft-start Coefficient) Thermistor Temperature Monitoring Circuit. function and compensation for the float voltage control Under normal operation, tie a thermistor from the NTC pin loop and compensation for the charge current control to the GNDSENS pin and a resistor of equal value from NTC loop. Tie a soft-start/compensation capacitor between this to VIN. When the voltage on this pin is above 0.74VIN (Cold, pin and GNDSENS. 0°C) or below 0.29VIN (Hot, 50°C), charging is disabled
TIMER (Pin 15):
Timer Capacitor. The timer period is set and the CHRG pin blinks. When the voltage on NTC comes by placing a capacitor, C back between 0.74V TIMER, to GNDSENS. Set CTIMER IN and 0.29VIN, the timer continues to: where it left off and charging resumes. There is approxi- mately 3°C of temperature hysteresis associated with CTIMER = Time (Hrs) • 0.0733 (µF) each of the input comparators. If the NTC function is not where time is the desired charging time. used connect the NTC pin to GNDSENS. This will disable all of the NTC functions. NTC should never be pulled above Connect this pin to IDET to disable the timer. Connect this V pin to GNDSENS to end battery charging when I IN. BAT drops below the IDET charge rate threshold.
PROG (Pin 12):
Charge Current Program. The RPROG resistor connects from this pin to GNDSENS, setting the
BATSENS (Pin 16):
Battery Sense Input. An internal resis- current: tor divider sets the final float voltage at this pin. The resistor divider is disconnected in sleep mode or when k R = 1 110 . EN = H to reduce the battery drain current. Connect this pin PROG IBAT(AMPS) to the positive battery terminal. where I
Exposed Pad (Pin 17):
Ground. This pin must be soldered BAT is the high rate battery charging current. to the PCB ground (PGND) for electrical contact and rated thermal performance. 4001f 6
U U U PI FU CTIO S FAULT (Pin 10):
Battery Fault. This pin is a logic high if a
IDET (Pin 13):
Charge Rate Detection Threshold. Connect- shorted battery is detected or if a temperature fault is ing a resistor, RIDET to GNDSENS programs the charge detected. A temperature fault occurs with the temperature rate detection threshold. If RIDET = RPROG, CHRG provides monitor circuit enabled and the thermistor temperature is an IBAT/10 indication. For other thresholds see the Appli- either below 0°C or above 50°C (typical). cations Information section.
NTC (Pin 11):
Input to the NTC (Negative Temperature
SS (Pin 14):
Soft-Start/Compensation. Provides soft-start Coefficient) Thermistor Temperature Monitoring Circuit. function and compensation for the float voltage control Under normal operation, tie a thermistor from the NTC pin loop and compensation for the charge current control to the GNDSENS pin and a resistor of equal value from NTC loop. Tie a soft-start/compensation capacitor between this to VIN. When the voltage on this pin is above 0.74VIN (Cold, pin and GNDSENS. 0°C) or below 0.29VIN (Hot, 50°C), charging is disabled
TIMER (Pin 15):
Timer Capacitor. The timer period is set and the CHRG pin blinks. When the voltage on NTC comes by placing a capacitor, C back between 0.74V TIMER, to GNDSENS. Set CTIMER IN and 0.29VIN, the timer continues to: where it left off and charging resumes. There is approxi- mately 3°C of temperature hysteresis associated with CTIMER = Time (Hrs) • 0.0733 (µF) each of the input comparators. If the NTC function is not where time is the desired charging time. used connect the NTC pin to GNDSENS. This will disable all of the NTC functions. NTC should never be pulled above Connect this pin to IDET to disable the timer. Connect this V pin to GNDSENS to end battery charging when I IN. BAT drops below the IDET charge rate threshold.
PROG (Pin 12):
Charge Current Program. The RPROG resistor connects from this pin to GNDSENS, setting the
BATSENS (Pin 16):
Battery Sense Input. An internal resis- current: tor divider sets the final float voltage at this pin. The resistor divider is disconnected in sleep mode or when k R = 1 110 . EN = H to reduce the battery drain current. Connect this pin PROG IBAT(AMPS) to the positive battery terminal. where I
Exposed Pad (Pin 17):
Ground. This pin must be soldered BAT is the high rate battery charging current. to the PCB ground (PGND) for electrical contact and rated thermal performance. 4001f 6
