Other Parts Discussed in Thread: BQ25898, BQ25910, BQ25898D
Hi
The customer test with the BQ25910EVM, The efficiency test result is about 1% lower than datasheet. For example, at the peak efficiency (VBUS = 5V, VBAT = 3.8V, charging current 1.1A), the measured efficiency is 94.5%.
The register set as below:
I2C address |
Reg address |
Write command |
description |
6A |
00 |
C8 |
Master HIZ enable |
6A |
07 |
8D |
Master WD disable |
4B |
05 |
DD |
25910 WD reset |
4B |
05 |
8D |
25910 WD disable |
4B |
06 |
3B |
25910 CHG enable |
Test point as below:
Input voltage: GND_ s & VUS2_ S
Input current: R19 (R21 mentioned in datasheet is not welded on the board and bypasses ron_qblk)
Output voltage: Vout_ 910_ S (BAT_S in datasheet is unreasonable, BAT_S is connected with bq25898) & GND_ S
Output current: R20
Ambient temperature: 25 ~ 30 ℃. The SW and fly cap waveforms of bq25910 are normal.
VBUS=5V,VBAT=3.8V。 VBUS and VBAT are adjust slightly according to the change of charging current.
What other factors will affect the efficiency of the test?
Waiting for your reply.
Thanks
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