MAX1870AETJ+ Maxim Integrated Products, MAX1870AETJ+ Datasheet - Page 13

• Manufacturer Part Number: MAX1870AETJ+
• Description: Battery Management Li+ Step Up/Step Down Battery Charger
• Manufacturer: Maxim Integrated Products

Specifications of MAX1870AETJ+

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

20, 21
PIN
12
13
14
15
16
17
18
19
22
23
24
25
26
27
28
29
30
31
32
Paddle
CELLS
NAME
PGND
SHDN
DBST
DLOV
CSSN
CSSS
CSSP
BATT
BLKP
DCIN
CSIN
CSIP
ICTL
VHN
IINP
VHP
DHI
I.C.
I.C.
______________________________________________________________________________________
Charge-Current Control Input. Drive ICTL from V
Setting the Charge Current section. Drive ICTL to GND to disable charging.
Cell-Count Selection Input. Connect CELLS to GND for two Li+ cells. Float CELLS for three Li+ cells, or
connect CELLS to REFIN for four Li+ cells.
Input-Current Monitor Output. IINP is a replica of the input current sensed by the MAX1870. It represents
the sum of the current consumed by the charger and the current consumed by the system. IINP has a
transconductance of 2.8µA/mV.
Shutdown Comparator Input. Pull SHDN low to stop charging. Optionally connect a thermistor to stop
charging when the battery temperature is too hot.
Battery-Voltage Feedback Input
Charge Current-Sense Negative Input
Charge Current-Sense Positive Input. Connect a current-sense resistor from CSIP to CSIN. Connect a
2.2µF capacitor from CSIP to GND.
Power Connection for Current-Sense Amplifier. Connect BLKP to BATT.
Internally Connected. Do not connect this pin.
Step-Up Power MOSFET (NMOS) Gate-Driver Output
Power Ground
Internally Connected. Do not connect this pin.
Low-Side Driver Supply. Bypass DLOV with a 1µF capacitor to GND.
Power Connection for the High-Side MOSFET Driver. Bypass VHP to VHN with a 1µF or greater ceramic
capacitor.
High-Side Power MOSFET (PMOS) Driver Output. Connect to the gate of the high-side step-down
MOSFET.
Power Connection for the High-Side MOSFET Driver. Bypass VHP to VHN with a 1µF or greater ceramic
capacitor.
Negative Terminal for Current-Sense Resistor for Charger Current. Connect a 2.2µF capacitor from CSSN
to GND.
Negative Terminal for Current-Sense Resistor for System Load Current
Positive Terminal for Input Current-Sense Resistors. Connect a current-sense resistor from CSSP to
CSSN. Connect an equivalent sense resistor from CSSP to CSSS.
DC Supply Voltage Input. Bypass DCIN with a 1µF or greater ceramic capacitor to power ground.
Paddle. Connect to GND.
FUNCTION
REFIN
Li+ Battery Charger
Step-Up/Step-Down
/ 32 to V
Pin Description (continued)
REFIN
to adjust the charge current. See the
13