PCF1178CT NXP Semiconductors, PCF1178CT Datasheet - Page 4

• Manufacturer Part Number: PCF1178CT
• Manufacturer: NXP Semiconductors

Specifications of PCF1178CT

• Operating Supply Voltage (typ): 3.3/5V
• Number Of Digits: 4
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Package Type: SO
• Pin Count: 28
• Mounting: Surface Mount
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 6V
• Lead Free Status / Rohs Status: Compliant

Philips Semiconductors
FUNCTIONAL DESCRIPTION AND TESTING
Outputs
The circuit outputs 1 : 2 multiplexed data (duplex) to the
LCD. Generation of BP1 and BP2 (three-level backplane
signals) and the output signals are shown in Fig.4.
1997 Apr 16
4-digit duplex LCD car clock
TIME
TIME
AM
PM
Fig.3 Typical displays.
PM
a. 12-hour mode.
b. 24-hour mode.
E1
(b)
(a)
G1
D1
A1
C1
B1
Fig.2 Segment designation of LCD.
MSA994
F2
E2
MSA993
G2
D2
A2
C2
B2
4
The average voltages across the segments are:
1. V
2. V
SEGMENT
COL
OFF
OFF
ON(RMS)
OFF(RMS)
ON
ON
1
Fig.4 Backplane and output signals.
E3
F3
MSB226
= 0.79 V
= 0.35 V
SEGMENT
BP1
BP2
OFF
OFF
ON
ON
A3
G3
D3
2
DD
DD
V DD /2
V DD /2
.
V DD
V DD
V DD
V DD
V DD
V DD
C3
B3
0
0
0
0
0
0
F4
E4
G4
D4
A4
Product specification
15.625 ms
MLB251
PCF1178C
C4
B4