Key facts
- Brand
- Philips
- Model
- PCF1178C
- Category
- Other Electronics
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- Electronics
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- 3
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- EN
- Last added
- 2022-11-25
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Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
The PCF1178C is a single-chip, 4.19 MHz CMOS car clock circuit designed to drive a 4-digit duplex liquid crystal display (LCD). It features an internal voltage regulator that is electrically programmable for various LCD voltages and includes time calibration that is also electrically programmable via an on-chip EEPROM, eliminating the need for trimming capacitors. The device operates in either 12-hour or 24-hour modes and is battery-operated via an internal voltage regulator and an external resistor.
The circuit provides hours, minutes, and seconds functions controlled by two external single-pole, single-throw switches. It includes features such as a temperature-compensated LCD voltage adjuster for good contrast, a 1 Hz set mode, and a test speed-up mode. The document provides comprehensive information on pin configurations, functional descriptions, operating conditions, limiting values, and programming procedures for the device.
Philips PCF1178C specifications
| Oscillator Frequency | 4.19 MHz |
|---|---|
| Operating Ambient Temperature | -40 to +85 °C |
| Package Type | 28-lead plastic SMD (SO28) |
| Supply Voltage Range | 3 to 6 V |
| Supply Current | 700 µA (typical) |
| Crystal Frequency Tolerance | ±30×10⁻⁶ |
| External Capacitance | 47 µF |
Source: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
All Philips PCF1178C documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
How is the 12-hour or 24-hour mode selected?
The mode is selected by connecting the MODE pin to V DD for 12-hour mode or to V SS for 24-hour mode.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
How is the LCD voltage programmed?
Programming is enabled by setting SEL to open-circuit and applying a level of V DD−5 V to V PP.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
What is the oscillator frequency of the PCF1178C?
The device includes a 4.19 MHz oscillator.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
How is the LCD voltage adjusted?
The internal voltage regulator is electrically programmable for various LCD voltages via the VPP pin.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
How is the LCD voltage adjusted?
The adjustable voltage regulator controls the supply voltage in relation to temperature for good contrast, with programming done via the DATA input and SEL pin.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet
What is the operating ambient temperature range for the PCF1178C?
The device operates within an ambient temperature range of -40 to +85 °C.
From: Philips PCF1178C 4-digit Duplex LCD Car Clock Datasheet