Use the following steps for charge mode
verification, including precharge, CC and CV phases for boost operation:
- PS1 and Load #1 should be on
from Section 2.4.1. In the EVM GUI, it is generally recommended to read REG22-REG27 (or READ
ALL REGISTERS) one time in order to show all of the interrupts (from status
changes, automated routine completion, faults) that occurred since the last
read. Reading those registers a second clears the interrupts. After reading
the registers,
- Verify ➡ REG1B
reports all Normal, meaning no DPM loops active and no WD timer
fault (bits 7-4), VAC1 Present (bit2), VBUS Present (bit 0) and
Power Good (bit 3)
- Reinstall the shunt on jumper
J19 to enable charge
- Verify ➡ STAT
LED (D14) is lit
- Take measurements as follows:
- Measure ➡
VVBUS-PGND (TP21 and TP45) = 5.0 V ±0.2 V
- Measure ➡
VBAT-PGND (TP27 and TP46) = 5.0 V ±0.2 V
- Measure ➡
IBAT_SENSE (voltage across 0.01-Ω resistor between
TP17 and TP18) = 240 mA ±60 mA
- Click READ ALL
REGISTERS and Verify ➡ REG1Cb[7:5] reports precharge
- Increase Load #1 regulation
voltage to 8.0 V and take measurements as follows:
- Measure ➡
VVBUS-PGND (TP21 and TP45) = 5.0 V ±0.2 V
- Measure ➡
VBAT-PGND (TP27 and TP46) = 8.0 V ±0.1 V
- Measure ➡
IBAT_SENSE (voltage across 0.01-Ω resistor between
TP17 and TP18) = 500 mA ±50 mA
- Measure ➡
IVAC1_SENSE (voltage across 0.01-Ω resistor between
TP1 and TP2) = 900 mA ±60 mA
- Click READ ALL
REGISTERS and Verify ➡ REG1Cb[7:5] reports fast charge
- Increase Load #1 regulation
voltage to 8.4 V and take measurements as follows:
- Measure ➡
VBAT-PGND (TP27 and TP46) = 8.4 V ±0.04 V
- Measure ➡
IBAT_SENSE (voltage across 0.01-Ω resistor between
TP17 and TP18) = 0 mA ±10 mA
- Click READ ALL
REGISTERS and Verify ➡ REG1Cb[7:5] reports termination
- Helpful hints when changing
voltages and register settings during charge mode:
- If increasing charge
current or adding a load at the SYS J3 terminal, disabling the
EN_ILIM (EN_EXTLIM) bit using 8-bit register tab/Charger Single-bit
Registers/REG14b[1] and increasing the IINDPM register setting in
16-bit register tab/Charger Multi-bit Registers/REG06b[8:0] will
likely be needed.
- If increasing the input
voltage above 8 V for the charger to enter buck mode, increase the
VAC_OVP from 7 V default using 8-bit register tab/Charger Multi-bit
Registers/REG10b[5:4].
- The battery
configuration is set at startup using the PROG pin (Jumpers JP24 to
JP31). The battery configuration can also be changed using 16-bit
register tab/Charger Multi-bit Registers/REG0Ab[7:6]. Note that the
SYSMIN and charge current charge with cell configuration.
- The status, fault and
interrupt bits report are helpful debug tools.