
Rev. 1.00
124
October 26, 2018
Rev. 1.00
125
October 26, 2018
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
• For input voltages 0 > V
IN
> -0.2V, the PGA operates in the inverting mode and the PGA output
is obtained using the formula below. Note that if the input voltage is negative, it cannot be lower
than -0.2V which will result in current leakage.
V
OUT
=-(R2/R1)×V
IN
Input Offset Calibration
The OCP circuit has four operating modes controlled by the OCPEN[1:0] bit field, one of them is
calibration mode. In calibration mode, operational amplifier and comparator offset can be calibrated.
Operational Amplifier Input Offset Calibration
Step1. Set OCPEN[1:0]=11, OCPOOFM=1, OCPCOFM=0 and OCPORSP=1, the OCP will operate
in the operational amplifier input offset calibration mode.
Step2. Set OCPOOF[5:0]=000000 and then read the OCPCOUT bit.
Step3. Increase the OCPOOF[5:0] value by 1 and then read the OCPCOUT bit.
If the OCPCOUT bit state has not changed, then repeat Step 3 until the OCPCOUT bit state
has changed.
If the OCPCOUT bit state has changed, record the OCPOOF value as V
OOS1
and then go to
Step 4.
Step4. Set OCPOOF[5:0]=111111 and read the OCPCOUT bit.
Decrease the OCPOOF[5:0] value by 1 and then read the OCPCOUT bit.
If the OCPCOUT bit state has not changed, then repeat Step 5 until the OCPCOUT bit state
has changed.
If the OCPCOUT bit state has changed, record the OCPOOF value as V
OOS2
and then go to
Step 6.
Step5. Restore the operational amplifier input offset calibration value V
OOS
into the OCPOOF[5:0] bit
field. The offset Calibration procedure is now finished.
Where V
OOS
=(V
OOS1
+V
OOS2
)/2
Note: S4 is off. In this mode, the operational amplifier outputs to OCPCOUT bypassing the comparator.
Comparator Input Offset Calibration
Step1. Set OCPEN[1:0]=11, OCPCOFM=1 and OCPOOFM=0, the OCP will now operate in the
comparator input offset calibration mode.
Step2. Set OCPCOF[4:0]=00000 and read the OCPCOUT bit.
Step3. Increase the OCPCOF[4:0] value by 1 and then read the OCPCOUT bit.
If the OCPCOUT bit state has not changed, then repeat Step 3 until the OCPCOUT bit state
has changed.
If the OCPCOUT bit state has changed, record the OCPCOF value as V
COS1
and then go to
Step 4.
Step4. Set OCPCOF[4:0]=11111 and then read the OCPCOUT bit.
Step5. Decrease the OCPCOF[4:0] value by 1 and then read the OCPCOUT bit.
If the OCPCOUT bit state has not changed, then repeat Step 5 until the OCPCOUT bit state
has changed.
If the OCPCOUT bit state has changed, record the OCPCOF value as V
COS2
and then go to
Step 6.