Texas Instruments bq24725, Руководство пользователя

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Test Summary
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2.4 Procedure
2.4.1 AC Adapter Detection Threshold
1. Be sure to follow EQUIPMENT SETUP steps. Turn on PS#2.
2. Turn on PS#1.
3. Increase the output voltage of PS#1 to 19.5 V.
Measure
→
V(TP(ACDET)) = 2.6 V
±
0.1 V
Measure → V(TP(ACOK)) = 3.3 V ± 0.1 V
Measure
→
V(J2(SYS)) = 19.5 V
±
0.5 V
Measure → V(TP(REGN)) = 6 V ± 0.5 V
Measure
→
V(TP(ACDRV, CMSRC)) = 6 V
±
0.5 V
Measure → V(J2(BAT, GND)) = 1 V ± 1 V
2.4.2 Charger Parameters Settings
1. In the software main window, click all the Read buttons. Make sure no error information is generated.
2. If an error information window pops up that reads "USB Error. Ensure USB cable is connected and
Driver is working," perform the following steps.
• Click OK. Close main window (shown in Figure 3 ), and disconnect the USB cable.
• Check the 3.3-V power supply (PS#2) and power supply #1 (PS#1) voltage on the EVM board.
• Disconnect any uncertain SMBus connections. Plug in the USB cable into the original EVM2300
installation USB port.
• Open the bq24725 evaluation software. The main window of the software is shown in Figure 3 .
3. Type in "512" (mA) in the Charge Current DAC, and click the Write button. This sets the battery charge
current regulation threshold.
4. Type in "12592" (mV) in the Charge Voltage DAC, and click the Write button. This sets the battery
voltage regulation threshold.
Measure
→ V(J2(BAT)) = 12.6 V ± 200 mV
2.4.3 Charge Current and AC Current Regulation (DPM)
1. Type in "7905" in the Charge Option, and click the Write button. This disables charging.
2. Connect the Load #2 in series with a current meter (multimeter) to J2 (BAT, GND). Ensure that a
voltage meter is connected across J2 (BAT, GND). Turn on the Load #2. Use the constant voltage
mode. Set the output voltage to 10.5 V.
3. Turn on the power of the Load #1. Set the load current to 3 A ± 50 mA but disable the output. The
setup is now like Figure 4 for HPA542. Ensure that Ibat = 0 A ± 10 mA and Isys = 0 A ± 10 mA.
6 bq24725EVM Evaluation Module SLUU439A – August 2010 – Revised May 2011
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