I have a question about the expected charging profile characteristics of the BQ24296. My understanding is that the IC performs constant current charging until the charging voltage and then charges by constant voltage. I have noticed that the CV charging starts below the charging voltage. I have 2 examples:
1. BQ24296 default settings(charges to 4.208 V), no host. Current limit set by ILIM resistor to 500 mA.
CV charging appears to start at 4.188 V.
2. Host configured charging(charging voltage 4.0 V). Current is set at 490 mA using 20 percent reduction. CV charging appears to start when VBat = 3.96 V.
Initial register settings:
reg[0x0] = 0x24
reg[0x1] = 0x1f
reg[0x2] = 0x79
reg[0x3] = 0x10
reg[0x4] = 0x7e
reg[0x5] = 0xba
reg[0x6] = 0x73
reg[0x7] = 0x4b
System configuration for both cases:
The BQ24296 is in system.
Input voltage at VBUS pins: 4.7 V
Capability of input source: 5 V, 2A
Battery Voltage: 4.2 V, 980 mAH
I do not have an evaluation board to compare.
Is this behavior expected?
