MC68HC05JJ6 Datasheet, PDF (125/216 Pages) Freescale Semiconductor, Inc – General Release Specification Microcontrollers

V_CAP
V_X
t_DIS
t_DIS
(MIN)
Analog Subsystem
t_DIS
(MIN)
V_MAX
t_CHG
V_X = ^{tCHG x ICHG}
C_EXT
CHG
COMP2
TOF
OCF
ICF
0
1
2
31
2
Point
Action
Software/Hardware Action
Begin initial discharge and select
0
mode 1 by clearing CHG and
Software write
ATD2 and setting ATD1 in the ACR
1 V_CAP falls to V_SS.
Wait out minimum t_DIS time
2
Stop discharge and begin charge by
setting CHG control bit in ACR.
Software write
V_CAP rises to V_X and comparator 2
3
output trips, setting CPF2 and
CMP2, which clears CHG control
bit in the ACR. Reset CPF2 by
Wait out t_CHG time
CPF2 clears CHG control bit
writing a 1 to CPFR2.
Dependent Variable(s)
Software
V_MAX, I_DIS, C_EXT
Software
V_X, I_CHG, C_EXT
Figure 8-9. A/D Conversion — Manual/Auto Discharge Control (Mode 1)
MC68HC05JJ6/MC68HC05JP6 — Rev. 3.2
Freescale Semiconductor
Analog Subsystem
General Release Specification
125