EVM Considerations
2
EVM Considerations
Refer to the data sheet for specific details on the charger ICs. The bq24250, bq24251, and bq24257
devices are featured with a high-efficiency switch-mode charger. It has integrated power FETs able to
charge at up to a 2-A charging rate, and an integrated 50-mA LDO. In I
2
C mode, the bq24250, bq24251,
and bq24257 devices have programmable battery charge voltage (V
BATREG
), charge current (I
CHG
), input
current limit (I
LIM
), and input over-voltage protection threshold (V
OVP
).
The charge current and the input current limit are programmed using external resistors (R
ISET
and R
ILIM
)
connected from the ISET and ILIM pins to ground. The range of these resistors can be found in the
datasheet. Both of these currents can be programmed up to 2 A. The bq24250, bq24251, and bq24257
devices also have complete system-level protection such as input undervoltage lockout (UVLO), input
over-voltage protection (OVP), battery OVP, sleep mode, thermal regulation and thermal shutdown,
voltage-based JEITA-compatible NTC monitoring input, and safety timer. PSE is also available – notify
your local TI representative.
3
Recommended Operating Condition
Specification
Test Condition
Min
Typ
Max
Units
Input DC voltage, VIN
Recommended input voltage range
4.35
10.5
V
Input current
Recommended input current range
2
A
Charge current
Fast charge current range
0.5
2
A
Output regulation voltage
Standalone mode or I
2
C default mode
4.2
V
Output regulation voltage
I
2
C host mode: operating in voltage regulation,
3.5
4.44
V
programmable range
LDO
LDO output voltage
4.9
V
3
SLUUA08A – March 2013 – Revised April 2013
bq2425xEVM-150, Single-Cell Li-Ion Switch-Mode Charger
Copyright © 2013, Texas Instruments Incorporated