HT37A70/60/50/40/30/20
HT37A20
Pad Name
Configuration
Option
I/O
Function
VDD
Positive digital power supply
¾
¾
¾
¾
¾
¾
¾
¾
VDD_DAC
VSS
Positive DAC circuit power supply
Negative digital power supply, ground
Negative DAC power supply, ground
VSS_DAC
Bidirectional 8-bit input/output port. Each pin can be configured as a wake-up
input by configuration option. Software instructions determine if the pin is a
CMOS output or Schmitt Trigger input. Configuration options determine if all
pins on this port have pull-high resistors. Pins PA5, PA6 and PA7 are
pin-shared with INT, TMR0 and TMR1, respectively.
PA0~PA4
PA5/INT
Pull-high
Wake-up
I/O
I/O
PA6/TMR0
PA7/TMR1
Bidirectional 4-bit input/output port. Software instructions determine if the pin
is a CMOS output or Schmitt Trigger input. A configuration option determines
if all pins on this port have pull-high resistors. Pins PC0 ~ PC3 are pin-shared
with K0 and K3, respectively (K0~K3 are CR/F function).
PC0/K0~
PC3/K3
Pull-high
Pull-high
Bi-directional 4-bit I/O port. Software instructions determined the CMOS out-
put or Schmitt trigger with a pull-high resistor (determined by pull-high option:
by option).
PD0/RCOUT
PD1/RR
I/O
PD2/RC
Pins PD0~PD3 are pin-shared with CR/F OSC input pins RCOUT, RR, RC
and CC.
PD3/CC
RCOUT, RR, RC and CC control pin for CR/F Function.
RCH
RES
O
I
Audio right channel output
¾
¾
Schmitt Trigger reset input, active low
OSC1, OSC2 are connected to an external RC network or external crystal,
determined by configuration option, for the internal system clock. If the RC
system clock option is selected, pin OSC2 can be used to measure the sys-
tem clock at 1/8 frequency.
OSC1
OSC2
I
Crystal or RC
O
Note: 1. Each pin on PA can be programmed through a configuration option to have a wake-up function.
2. Individual pins can be selected to have pull-high resistors.
3. Because the two timers are used by MIDI the external timer pin functions are disabled.
Absolute Maximum Ratings
Supply Voltage ..........................VSS-0.3V to VSS+5.5V
Input Voltage .............................VSS-0.3V to VDD+0.3V
Storage Temperature ...........................-50°C to 125°C
Operating Temperature ..........................-20°C to 70°C
I
OL Total ..............................................................150mA
I
OH Total............................................................-100mA
Total Power Dissipation .....................................500mW
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 reliability.
Rev. 1.00
11
February 17, 2009
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
