Pad Description

Pad Name

I/O

Options

Description

PA0/BZ

PA1/BZ

PA2

PA3/PFD

PA4~PA7

I/O

Wake-up

Pull-high

or None

CMOS or

NMOS

PA0~PA7 constitute an 8-bit bidirectional input/output port with Schmitt trig-

ger input capability. Each pin on the port can be configured as a wake-up in-

put by configuration options. PA0~PA3 can be configured as a CMOS output

or NMOS input/output with or without pull-high resistor by configuration op-

tions. PA4~PA7 are always pull-high NMOS input/output. PA0~PA1 can be

setup as I/O pins or buzzer outputs by a configuration option. PA3 can be

setup as an I/O pin or as a PFD output also by a configuration option.

PB0/INT

PB2/TMR

I

¾

PB0 and PB2 constitute a 2-bit Schmitt trigger input port. Each pin on the port

has a pull-high resistor. PB0 can be setup as an input pin or an external inter-

rupt control pin (INT) by software application. PB2 can be setup as an input

pin or as a timer/event counter input pin TMR also by software.

VLCD

I

¾

LCD power supply

V1, V2, C1, C2

I

¾

Voltage pump

COM0~COM2

COM3/SEG14

O

1/2, 1/3or1/4

Duty

SEG14 can be setup as a segment or as a common output driver for LCD

panel by a configuration option. COM0~COM2 are the outputs for LCD

panel.

SEG0~SEG13

O

¾

LCD driver outputs for LCD panel segments

OSC1

OSC2

I

O

Crystal or RC

OSC1 and OSC2 are connected to an RC network or a crystal, a

configuration option for the internal system clock. In the case of RC opera-

tion, OSC2 is the output terminal for 1/4 system clock.

The system clock may come from the RTC oscillator. If the system clock co-

mes from RTC OSC, these two pins can be left floating.

OSC3

OSC4

I

O

RTC or

System Clock

Real time clock oscillators. OSC3 and OSC4 are connected to a 32768Hz

crystal oscillator for timing purposes or to a system clock source (depending

upon the configuration options).

VSS

¾¾

Negative power supply, ground

VDD

¾¾

Positive power supply

RES

I

¾

Schmitt trigger reset input, active low

Absolute Maximum Ratings

Storage Temperature ............................

-50°Cto125°C

Operating Temperature...........................

-40°Cto85°C

-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 reliabil-

ity.

HT49R10A-1/HT49C10-1

Rev. 1.20

3

July 27, 2007