MAX1501 Datasheet, PDF (14/15 Pages) Maxim Integrated Products – Highly Integrated, Linear Battery Charger with Thermal Regulation for Portable Applications

Highly Integrated, Linear Battery Charger with
Thermal Regulation for Portable Applications
5V
5.1kΩ
4.1kΩ
2.24kΩ
RT = 10kΩ
AT +25°C
10kΩ 3.66kΩ
3kΩ
100kΩ
5V
3kΩ
100kΩ
200kΩ
3kΩ
1kΩ
IN
MAX1501
CHGEN
GND
T_BATT
R_T
0°C 27.28kΩ
1kΩ
+25°C 10.00kΩ
+50°C 4.16kΩ
Figure 10. Battery Temperature Protection
Figure 10 shows a circuit that adds temperature protec-
tion to the battery. Install the thermistor as close to the
battery as possible to ensure accurate temperature mea-
surement. The output of this circuit is logic high when the
battery temperature is less than 0°C and greater than
+50°C. Driving CHGEN high disables the charger.
Layout and Bypassing
Connect IN and INP together as close to the device as
possible and bypass with a 1µF ceramic capacitor.
Bypass BATT to GND with a 10µF ceramic capacitor.
Provide a large copper GND plane to allow the exposed
paddle to sink heat away from the device. Connect the
battery to BATT as close to the device as possible to
provide the most accurate battery voltage sensing.
Make all high-current traces short and wide to minimize
voltage drops.
Chip Information
TRANSISTOR COUNT: 5717
PROCESS: BiCMOS
Pin Configuration
16 15 14 13
INP 1
12 BATT
IN 2
GND 3
MAX1501
11 ACOK
10 CHGEN
SETI 4
**EXPOSED PADDLE
9 MODE
5678
5mm x 5mm
THIN QFN
**CONNECT EXPOSED PADDLE TO GND
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