Pin Description - Holtek HT46RU75D-1 Manual

Pin Description

Pin Name I/O
PA0/BZ
PA1/BZ
PA2
PA3/PFD
I/O
PA4/TMR0
PA5/TMR1
PA6/INT
PA7
PB0/AN0~
I/O
PB7/AN7
PC0/TX
I/O
PC1/RX
¾
VLCD
¾
VMAX
¾
V1, V2, C1, C2
COM0~COM2 1/2, 1/3 or 1/4
O
COM3/SEG40
SEG0~SEG39 O
VOBGP AO
VOREG O
VOCHP O
¾
CHPC1
¾
CHPC2
ADIN
AO
ADIP
DOPAN,
DOPAP,
AI/AO
DOPAO,
DCHOP
DSRR,
DSRC, AI/AO
DSCC
OSC1 I
Crystal or RC
OSC2 O
OSC3 I
OSC4 O System Clock
RES I
¾
VDD
¾
VSS
¾
AVDD
¾
AVSS
Rev. 1.10
Options
Bidirectional 8-bit input/output port. Each individual pin on this port can
Wake-up be configured as a wake-up input by a configuration option. Software in-
Pull-high structions determine if the pin is a CMOS output or Schmitt trigger input.
Buzzer Configuration options determine which pins on this port have pull-high re-
PFD sistors. The BZ/BZ, PFD, TMR0/TMR1 and INT pins are shared with
PA0/1, PA3, PA4/5, and PA6, respectively.
Bi-directional 8-bit input/output port. Software instructions determine if
the pin is a CMOS output or Schmitt Trigger input. Configuration options
determine which pins on the port have pull-high resistors. PB is
Pull-high
pin-shared with the A/D input pins. The A/D inputs are selected via soft-
ware instructions Once selected as an A/D input, the I/O function and
pull-high resistor functions are disabled automatically.
Bi-directional 8-bit input/output port. Software instructions determine if
the pin is a CMOS output or Schmitt Trigger input. Configuration options
Pull-high determine which pins on the port have pull-high resistors.
PC0 can be chosen as an I/O pin or as a UART TX output by software.
PC1 can be chosen as an I/O pin or as a UART RX input by software.
¾
LCD power supply
¾
IC maximum voltage. Connected to VDD, VLCD or V1
¾
LCD voltage pump
COM0~COM3 are the LCD common outputs. A configuration option se-
lects the LCD duty-cycle. When either 1/3 or 1/2 duty is selected, the
Duty
COM3/SEG40 pin will be configured as SEG40.
Segment
LCD driver outputs for the LCD panel segments.
Output
¾
Band gap voltage output pin - for internal use
¾
Regulator output - 3.3V
¾
Charge pump output - requires external capacitor
¾
Charge pump capacitor, positive
¾
Charge pump capacitor, negative
OP external Resistor Analog output connection. ADIN connects to
¾
DOPAN by a resistor. ADIP connects to DOPAP by a resistor.
Dual Slope converter pre-stage OPA related pins. DOPAN is the OPA
¾
Negative input pin, DOPAP is the OPA Positive input pin, DOPAO is the
OPA output pin and DCHOP is the OPA Chopper pins.
Dual slope AD converter main function RC circuit. DSRR is the input or
¾
reference signal, DSRC is the Integrator negative input, and DSCC is the
comparator negative input.
OSC1, OSC2 are connected to an external RC network or crystal for the
internal system clock. If the RC system clock option is selected, pin
OSC2 can be used to monitor the system clock at 1/4 frequency.
RTC or OSC3, OSC4 are connected to a 32768Hz crystal to form a real time
clock for timing purposes or to form a system clock.
¾
Schmitt trigger reset input, active low
¾
Positive power supply
¾
Negative power supply, ground
¾
Analog positive power supply
¾
Analog negative power supply, ground
3
HT46RU75D-1
Description
January 10, 2008