Vin
Vout
Vbat
Suspend
DPPM Mode
Battery Supplement Mode
Normal Mode
Chip Disable
BAT Current - Vbat 0.1
W
EN ->VSS USB100
EN2 ->HI USB 500
t - Time - 1 ms/div
Test Summary
6
SLVU274E – November 2008 – Revised January 2017
Copyright © 2008–2017, Texas Instruments Incorporated
bq24072/3/4/5/9(T) and bq24230/2 1.5-A Single-Chip Li-Ion and Li-Polymer
Charge Management IC EVM
and supplements the input current. Verify that Vout has dropped just below the battery voltage and the
battery is supplying Ibat, ~(Vout/10
Ω
– 100 mA).
13. Set JMP4 (EN2) to HI to return to the ISET mode where the programmed current is ~0.9 A.
14. Set JMP3 to HI, and verify that the charging is disabled and that the CHG LED (D1) turns off. Verify
that the system is still powered by the input. See
.
15. Set JMP3 to VSS, and verify that charging continues and that D1 turn on.
16. Record the OUT voltage and battery charge current. Adjust R8 CCW until the input current starts to be
reduced (~2 turns). Note how the OUT voltage drops and the charge current is reduced as the input
current limit loops kicks in and limits the input current. Adjust R8 to its original position
17. On the bq24075 IC, set JMP2 HI, and verify that the BAT FET turns off and allows no charging or
discharging of the battery.
18. Adjust the R16 (TS-Pot) up or down until the TS threshold is reached. Verify that the charging current
is disabled. Return the TS resistance within the normal range and verify the continued charging
operation.
19. Allow the battery to continue to charge until the battery reaches voltage regulation, ~4.2 V ±40 mV for
bq24072/3/4/5/9(T) and 4.1 V ±4 mV for bq24079(T). Verify that the voltage is regulated as the current
tapers over the next one-to-two hours depending on the battery capacity. See
for a charge
profile (time in plot is not proportional to actual charge time).
20. Verify that the current tapers to around 90 mA (9 mV on DMM#3) when termination occurs. Note on
the ’72 and ’73 ICs that termination can be disabled by setting the TD pin HI (JMP2). Also note that on
’74, the ITERM resistor (R10) can adjust the termination threshold.
21. Verify that the LED, D1, turns off and the current drops to zero.
22. Turn off P/S#1, and allow the system load to discharge the battery until a refresh charge is initiated.
Verify that the battery voltage dropped to ~4.1 V for bq24072/3/4/5 and to 4.0 V for bq24079(T) prior to
refresh.
23. Verify that the LED, D1, did not turn on for the refresh cycle.
This concludes the procedure for demonstrating the features of this power path charger. See the data
sheet for more detailed explanations and instructive waveforms.
Figure 2. Modes of Operation Tested in Steps 11 Through 13
