Texas Instruments Evaluation Module for BQ25050 1A, Single-Input, Single Cell Li-Ion Battery Charger with 50-mA LDO BQ25 BQ25050EVM Scheda Tecnica

Codici prodotto

BQ25050EVM

Procedure

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Figure 3. Battery Load Circuit – Replacement for a Single Cell Li-Ion Battery

→

BAT+ to BAT– Voltage

Tracks P/S Input Voltage Minus 1 Diode Drop.

Procedure

4.1

Charger Operation with Minimum System Voltage Mode

4.1.1

Turn on PS#1, preset to 5.1 Vdc

Measure

→

V(J4(VLDO)) = 4.9 ±100 mV

4.1.2

For -001: Trim R7, and set TS pin voltage to 0.5 V ± 50 mV. In the software window, click on
enable.

For -002: Trim R7 and set TS pin voltage to 1 V ±50 mV.
For -001 and -002: Turn on PS#2 set to 2.3 V ±50 mV.

Observe

→

D1(/CHG) on – This is precharge mode and OUT is held at its minimum system
voltage while the adapter is present and the battery below this minimum voltage. This
allows system power-up with a discharged battery.

Measure

→

Iin = 180 mA ±30 mA

Measure

→

V(J2(OUT)) = 3.5 V ±200 mV

4.1.3

Increase PS#2 to ~3.3 Vdc to raise VBAT to 3 V ±50 mV

Observe

→

D1(/CHG) on –This is fast-charge constant current mode and OUT is held at its
minimum system voltage while the adapter is present and the battery below this
minimum voltage. This allows system power-up with a discharged battery.

For -001 Measure

→

Iin = 285 mA ±50 mA

For -002 Measure

→

Iin = 467 mA ±50 mA

Measure

→

V(J2(OUT)) = 3.5 V ±200 mV.

4.1.4

Increase PS#2 to ~4.1Vdc to raise VBAT to 3.8 V ±50 mV.

Observe

→

D1(/CHG) on – This is fast-charge constant current mode and the battery is
above the minimum OUT voltage (with adapter present) so that the external BAT
FET is enabled, and Vout and Vbat track.

For -001 Measure

→

Iin = 285 mA ±50 mA

For -002 Measure

→

Iin = 467 mA ±50 mA

Measure

→

V(J2(OUT)) = 3.8 V ±200 mV

bq25050/bq25060EVM

SLUU438 – July 2010