MAX1757 Maxim, MAX1757 Datasheet - Page 8

• Manufacturer Part Number: MAX1757
• Description: Stand-Alone / Switch-Mode Li Battery Charger with Internal 14V Switch
• Manufacturer: Maxim

Stand-Alone, Switch-Mode
Li+ Battery Charger with Internal 14V Switch
8
19, 20
9, 10
PIN
11
12
13
14
15
16
17
18
21
22
23
24
25
26
27
28
_______________________________________________________________________________________
1
2
3
4
5
6
7
8
FASTCHG
FULLCHG
ISETOUT
TIMER1
TIMER2
ISETIN
FAULT
NAME
PGND
SHDN
CSSN
CSSP
VADJ
BATT
CELL
DCIN
THM
GND
HSD
CCS
CCV
REF
BST
CCI
CS
VL
LX
Chip Power Supply. Output of the 5.4V linear regulator from DCIN. Bypass VL to GND with 2.2µF or larger
ceramic capacitor.
Input Current Limit Adjust. Use a voltage divider to set the voltage between 0 and V
Regulator section.
Battery Charging Current Adjust. Use a voltage divider to set the voltage between 0 and V
Charging Current Regulator section.
Thermistor Input. Connect a thermistor from THM to GND to set qualification temperature range. If unused,
connect a 10kΩ resistor from THM to GND. See Thermistor section.
4.2V Reference Voltage Output. Bypass REF to GND with 1µF or larger ceramic capacitor.
Analog Ground
Voltage Adjustment. Use a voltage divider to set the voltage between 0 and V
ulation voltage by ±5%. See Battery Regulation Voltage section.
Battery Voltage-Sense Input and Current-Sense Negative Input
High-Side Drain. This is the drain of the internal high-side FET. See Figure 3.
Cell-Count Programming Input. Connect CELL to GND or REF to set 1 or 3 cells, or leave unconnected to
set 2 cells.
Timer1 Adjustment. Connect a capacitor from TIMER1 to GND to set the prequalification, full-charge, and
top-off times. See Timers section.
Timer2 Adjustment. Connect a capacitor from TIMER2 to GND to set the fast-charge time. See Timers section.
Charge Fault Indicator. Open-drain output pulls low when charging terminates abnormally. See Table 1.
Fast-Charge Indicator. Open-drain output pulls low when charging with constant current.
Full-Charge Indicator. Open drain output pulls low when charging with constant voltage in full-charge state.
Shutdown Input. Drive SHDN low to disable charging. Connect SHDN to VL for normal operation.
Power Ground. Current from the low-side power MOSFET switch source flows through PGND.
Power Inductor Switching Node and High-Side Power MOSFET Source
Battery Current-Sense Positive Input. Connects to internal 0.1Ω resistor between BATT and CS.
High-Side MOSFET Gate Drive Bias. Connect a 0.1µF capacitor from BST to LX.
Charger Source Current Regulation Loop Compensation Point. See Compensation section.
Battery Charge Current Regulation Loop Compensation Point. See Compensation section.
Voltage Regulation Loop Compensation Point. See Compensation section.
Source Current-Sense Negative Input. See Input Current Regulator section.
Source Current-Sense Positive Input. See Input Current Regulator section.
Power-Supply Input. DCIN is the input supply for the VL regulator. Bypass DCIN to GND with a 0.1µF or
greater capacitor. See Detailed Description.
FUNCTION
REF
Pin Description
to adjust the battery reg-
REF
. See Input Current
REF
. See