HT46R12
Pin Description
Pin Name
I/O
Options
Description
PA0~PA2
PA3/PFD
PA4/TMR0
PA5, PA6
PA7/TMR1
Bidirectional 8-bit input/output port. Each bit can be configured as wake-up in-
put by options. Software instructions determine the CMOS output or Schmitt
trigger input with or without pull-high resistor (determined by pull-high options: bit
Pull-high
Wake-up
I/O
PA3 or PFD option). The PA3, PA4 and PA7 are pin-shared with PFD, TMR0 and TMR1 re-
spectively.
Bidirectional 4-bit input/output port. Software instructions determine the
CMOS output, Schmitt trigger input with or without pull-high resistor (deter-
PB0/AN0
PB1/AN1
PB2/AN2
PB3/AN3
I/O
Pull-high
mined by pull-high option: bit option) or A/D input.
Once a PB line is selected as an A/D input (by using software control), the I/O
function and pull-high resistor are disabled automatically.
Bidirectional 4-bit input/output port. Software instructions determine the
CMOS output, Schmitt trigger input with or without pull-high resistor (deter-
mine by pull-high option: port option).
PC0, PC1 and PC2 are pin-shared with C0VIN-, C0VIN+ and C0OUT respec-
tively. Once the Comparator 0 function is used, the internal registers related to
PC0, PC1 and PC2 cannot be used, and the I/O function and pull-high resistor
are disabled automatically. Software instructions determine the Comparator 0
PC0/C0VIN-
PC1/C0VIN+
PC2/C0OUT
PC3/C1OUT
C1VIN-
Pull-high
I/O or
I/O
Comparator function to be used.
C1VIN+ and C1VIN- are Comparator 1 input, C1OUT is pin-shared with PC3.
C1VIN+
Once the Comparator 1 function is used, the internal registers related to PC3
cannot be used, and the I/O function and pull-high resistor are disabled auto-
matically. Software instructions determine the Comparator 1 function to be
used.
Programmable pulse generator output pin, the pin is floating when the power is
first turned on. The PPG0 output level (active low or active high) can be se-
lected via configuration option.
PPG
O
¾
OSC1, OSC2 are connected to an RC network or a Crystal (determined by op-
tions) for the internal system clock. In the case of RC operation, OSC2 is the
output terminal for 1/4 system clock.
OSC1
OSC2
I
Crystal
or RC
O
RES
VDD
VSS
I
Schmitt trigger reset input. Active low.
Positive power supply
¾
¾
¾
¾
¾
Negative power supply, ground.
Absolute Maximum Ratings
Supply Voltage...........................VSS-0.3V to VSS+6.0V
Input Voltage..............................VSS-0.3V to VDD+0.3V
Storage Temperature............................-50°C to 125°C
Operating Temperature...........................-40°C to 85°C
Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² may
cause substantial damage to the device. Functional operation of this device at other conditions beyond those
listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliabil-
ity.
Rev. 1.20
3
February 24, 2006
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
