General Description

The CD4047B is capable of operating in either the monostable or astable mode. It requires an external capacitor (between pins 1 and 3) and an external resistor (between pins 2 and 3) to determine the output pulse width in the monostable mode, and the output frequency in the astable mode.

Features

■ Wide supply voltage range: 3.0V to 15V
■ High noise immunity: 0.45 VDD (typ.)
■ Low power TTL compatibility: Fan out of 2 driving 74L or 1 driving 74LS

Special Features

■ Low power consumption: special CMOS oscillator configuration
■ Monostable (one-shot) or astable (free-running) operation
■ True and complemented buffered outputs
■ Only one external R and C required

Monostable Multivibrator Features

■ Positive- or negative-edge trigger
■ Output pulse width independent of trigger pulse duration
■ Retriggerable option for pulse width expansion
■ Long pulse widths possible using small RC components by means of external counter provision
■ Fast recovery time essentially independent of pulse width
■ Pulse-width accuracy maintained at duty cycles approaching 100%

Astable Multivibrator Features

■ Free-running or gatable operating modes
■ 50% duty cycle
■ Oscillator output available
■ Good astable frequency stability
typical= ±2% + 0.03%/°C @ 100 kHz
frequency= ±0.5% + 0.015%/°C @ 10 kHz
deviation (circuits trimmed to frequency VDD = 10V ±10%)

Applications

• Frequency discriminators
• Timing circuits
• Time-delay applications
• Envelope detection
• Frequency multiplication
• Frequency division