µ
PD754144, 754244
27
Data Sheet U10040EJ2V1DS
7.5 Programmable Threshold Port (Analog Input Port)
The
µ
PD754244 provides analog input pins (PTH00, PTH01) whose threshold voltage (reference voltage) is
selectable within sixteen steps. The following operations can be performed with these analog input pins.
(1)
Comparator operation
(2)
4-bit resolution A/D converter operation (controlled by software)
Caution
Do not specify an on-chip pull-up resistor connection for Port 6 when using the programmable
threshold port.
Figure 7-7. Programmable Threshold Port Block Diagram
PTH00
PTH01
AV
REF
1
2
R
R
R
1
2
R
MPX
V
REF
PTHM7
PTHM
PTHM6
PTHM5
PTHM4
PTHM3
PTHM2
PTHM1
PTHM0
8
Operate/stop
Standby mode signal
+
–
+
–
PTH0
Programmable
threshold
port input latch (2)
Input buffer
Input buffer
Internal bus
*