Pin Description

Pin Name

I/O

Options

Description

PA0~PA2

PA3/PFD

PA4/TMR

PA5/INT

PA6~PA7

I/O

Pull-high

Wake-up

PA3 or PFD

Bidirectional 8-bit input/output port. Each individual bit on this port can be config-

ured as a wake-up input by configuration option. Software instructions determine

if the pin is a CMOS output or Schmitt trigger input. Configuration options deter-

mine which pins on this port have pull-high resistors. The PFD, TMR and external

interrupt input are pin-shared with PA3, PA4, and PA5 respectively.

PB0/AN0

PB1/AN1

PB2/AN2

PB3/AN3

PB4/AN4

I/O

Pull-high

Bidirectional 5-bit input/output port. Software instructions determine the CMOS

output or Schmitt trigger input with or without pull-high resistor. Configuration op-

tions determine which pins on this port have pull-high resistors. PB is pin-shared

with the A/D input pins. The A/D inputs are selected via software instructions

Once selected as an A/D input, the I/O function and pull-high resistor functions

are disabled automatically.

PD0/PWM

I/O

Pull-high

PD0 or PWM

Bidirectional 1-bit input/output port. Software instructions determine the CMOS

output or Schmitt trigger input with or without pull-high resistor. One configuration

option determines which pin on this port has pull-high resistor. PD0 is pin-shared

with the PWM output selected via configuration option.

OSC1

OSC2

I

O

Crystal or RC

OSC1, OSC2 are connected to an external RC network or external crystal (deter-

mined by configuration option) for the internal system clock. For external RC sys-

tem clock operation, OSC2 is an output pin for 1/4 system clock.

RES

I

¾

Schmitt trigger reset input, active low

VDD

¾¾

Positive power supply

VSS

¾¾

Negative power supply, ground

VREF

I

¾

A/D Converter Reference Input voltage pins. Connect this pin to the desired A/D

Absolute Maximum Ratings

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

-50°Cto125°C

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

-40°Cto85°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.

D.C. Characteristics

Ta=25

°C

Symbol

Parameter

Test Conditions

Min.

Typ.

Max.

Unit

Conditions

Operating Voltage

¾

2.2

¾

5.5

V

3.3

¾

5.5

V

Operating Current (Crystal OSC)

3V

ADC disabled

¾

0.6

1.5

mA

5V

¾

24

mA

Operating Current (RC OSC)

3V

ADC disabled

¾

0.8

1.5

mA

5V

¾

2.5

4

mA

Operating Current

5V

ADC disabled

¾

48

mA

Standby Current (WDT Enabled)

3V

No load, system HALT

¾¾

5

mA

5V

¾¾

10

mA

HT46R51/HT46R52

Rev. 1.40

3

July 12, 2005