1997 Apr 16

2

Philips Semiconductors

Product specification

4-digit duplex LCD car clock

PCF1178C

FEATURES

• Internal voltage regulator is electrically programmable

for various LCD voltages

• Time calibration is electrically programmable

(no trimming capacitor required)

• LCD voltage adjusts with temperature for good contrast

• 4.19 MHz oscillator

• 12-hour or 24-hour mode

• Operating ambient temperature: −40 to +85 °C

• 28-lead plastic SMD (SO28)

• 1 Hz set mode.

GENERAL DESCRIPTION

The PCF1178C is a single chip, 4.19 MHz CMOS car clock

circuit providing hours, minutes and seconds functions.

It is designed to drive a 4-digit duplex liquid crystal display

(LCD).

Two external single-pole, single-throw switches will

accomplish all time setting functions. Time calibration and

voltage regulator are electrically programmable via an

on-chip EEPROM. The circuit is battery-operated via an

internal voltage regulator and an external resistor.

ORDERING INFORMATION

Notes

1. See Fig.1 and Chapter “Package outline” for pin layout and package details.

2. See Chapter “Chip dimensions and bonding pad locations” for pad layout and package details.

TYPE NUMBER

PACKAGE

NAME

DESCRIPTION

VERSION

PCF1178CT

SO28

SOT136-1

PCF1178CU

−

−

PCF1178CU/10

−

−

PCF1178CU/5

−

−