HT66FW2230 Datasheet, PDF (113/148 Pages) Holtek Semiconductor Inc – Wireless Charger A/D Flash MCU

HT66FW2230
Wireless Charger A/D Flash MCU
Offset Calibration
The OCP circuit has 4 operating mode controlled by OCPM1~OCPM0. One of these modes is the
calibration mode. In the calibration mode, the OP and comparator offset can be calibrated.
OPAMP calibration:
• Step1: Set OCPM[1:0] =11, OCPAOFM=1, the OCP is now in the OPAMP calibration mode.
• Step2: Set OCPAOF4~OCPAOF0 =00000 then read the OCPAX bit status.
• Step3: Let OCPAOF=OCPAOF+1 then read the OCPAX bit status; if OCPAX is changed, record
the register data as VOS1.
• Step4: Set OCPAOF [4:0] 111111 then read the OCPAX bit status.
• Step5: Let OCPAOF=OCPAOF-1 then read the OCPAX bit status; if OCPAX is changed, record
the register data as VOS2.
• Step6: Restore VOS = (VOS1 + VOS2)/2 to the OCPAOF register. The calibration is now finished.
Comparator calibration:
• Step1: Set OCPM[1:0] =11, OCPCOFM=1, the OCP is now in the comparator calibration mode
• Step2: Set OCPCOF [4:0] =00000 then read the OCPCX bit status.
• Step3: Let OCPCOF=OCPCOF+1 then read the OCPCX bit status; if OCPCX is changed, record
the register data as VOS1.
• Step4: Set OCPCOF [4:0] =11111 then read the OCPCX bit status.
• Step5: Let OCPCOF=OCPCOF-1 then read the OCPCX bit status; if OCPCX data is changed,
record the register data as VOS2.
• Step6: Restore VOS = (VOS1 + VOS2)/2 to the OCPCOF register. The calibration is now finished.
OCP Register Description
The OCP0 and OCP1 registers are the OCP control registers which control the OCP operation mode,
PGA and filter functions. The OCPREF register is used to provide the reference voltages for the over
current protection. OCPACAL and OCPCCAL are used to cancel out the operational amplifier and
comparator input offset.
OCPC0 Register
Bit
7
6
5
4
3
2
1
0
Name OCPM1 OCPM0
—
—
—
—
—
—
R/W
R/W
R/W
—
—
—
—
—
—
POR
0
0
—
—
—
—
—
—
Bit 7~6
Bit 5~0
OCPM1~OCPM0: Mode selection
00: OCP function disable, S1, S3 on , S0,S2 off
01: OCP function enable in non-Inverter mode, S0, S3 on , S1,S2 off
10: OCP function enable in Inverter mode , S1, S2 on , S0,S3 off
11: OCP function enable in 0V input mode, S1, S3 on , S0,S2 off
Note: Disable means OPA, CMP, DAC, Filter all off & comparator output=low.
Unimplemented, read as 0
Rev. 1.20
113
January 3, 2017