Datasheet

Test Summary

www.ti.com

2.4 Recommended Test Procedure

The following test procedure is useful for evaluating the charger IC outside of a real system, if no battery

is available to connect to the output and a simulated battery is needed.

2.4.1 System Voltage and Output Current (bq24272 only)

1. Ensure that the Section 2.3 steps are followed.

2. Connect the output of PS #1 in series with CM #1 to J2 (IN, GND).

3. Connect voltage meter 1 (VM #1) across J1 or TP1 and J3 (IN, GND).

4. With PS #2 disabled, turn on PS #1.

5. Ensure the electronic load is on current mode and set the current to 1 A or turn down the resistor

decade box until CM #3 measures 1000 ±100 mA.

6. Measure:

Measure on VM #3 → V(J4(SYS), J8(GND)) = 3.7 ±150 mV.

Observe → D1 and D2 are on.

7. Move JP2 (CD) = HI.

8. Measure on VM #3 → V(J4(SYS), J8(GND)) = 0 V.

9. Disable PS #1 and disconnect electronic load or resistor box and CM #3 from the HPA759 board.

2.4.2 Charge Voltage and Current Regulation of IN

1. Ensure that the Section 2.3 steps are followed.

2. Connect the output of PS #1 in series with current meter (multimeter) #1 (CM #1) to J1 and J3 or J2

(IN, GND).

3. Connect voltage meter 1 (VM #1) across J1 or TP1 and J3 (IN, GND).

4. Move JP2 to HI.

5. Turn on PS #1 and PS #2 if used.

6. Return JP2 to LO.

7. Software setup:

• Press the READ button to obtain the current settings.

• Set Write On Change to ON if not already set.

• Set Reset Watchdog Timer to update every 5 seconds.

• Uncheck Disable Charging if checked.

• Check Enable STAT/INT Outputs.

• Set Battery Regulation Voltage to 4.20 V.

• Set USB Input Current Limit to 2.5 A.

• Set Charge Current to 1000 mA.

• Click the READ button at the top of the window, and confirm that the previous settings remain.

8. Adjust PS #2 so that the voltage measured by VM #2, across BAT and GND, measures 3.2 V ±50 mV.

9. Adjust the power supply so that VM #1 still reads 6 V ±100 mV if necessary then

Measure on CM #2 → I

CHRG

= 1000 mA ±100 mA

Measure on CM #1 → I

< 850 mA

Observe → D1 and D2 are on.

10. Turn off PS #1 and PS #2.

WCSP-Packaged bq24272/273 Evaluation Modules SLUU916–April 2012

Submit Documentation Feedback