October 1987
Revised May 1999
CD4047BC
Low Power Monostable/Astable Multivibrator
■ True and complemented buffered outputs
General Description
The CD4047B is capable of operating in either the
■ Only one external R and C required
monostable or astable mode. It requires an external capac-
MONOSTABLE MULTIVIBRATOR FEATURES
itor (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.
■ Positive- or negative-edge trigger
■ Output pulse width independent of trigger pulse duration
■ Retriggerable option for pulse width expansion
Astable operation is enabled by a high level on the astable
input or low level on the astable input. The output fre-
quency (at 50% duty cycle) at Q and Q outputs is deter-
mined by the timing components. A frequency twice that of
Q is available at the Oscillator Output; a 50% duty cycle is
not guaranteed.
■ 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%
Monostable operation is obtained when the device is trig-
gered by LOW-to-HIGH transition at + trigger input or
HIGH-to-LOW transition at − trigger input. The device can
be retriggered by applying a simultaneous LOW-to-HIGH
transition to both the + trigger and retrigger inputs.
ASTABLE MULTIVIBRATOR FEATURES
■ Free-running or gatable operating modes
■ 50% duty cycle
A high level on Reset input resets the outputs Q to LOW, Q
to HIGH.
■ 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%)
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
Applications
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•
•
•
•
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Frequency discriminators
SPECIAL FEATURES
Timing circuits
Time-delay applications
Envelope detection
Frequency multiplication
Frequency division
■ Low power consumption: special CMOS oscillator
configuration
■ Monostable (one-shot) or astable (free-running)
operation
Ordering Code:
Order Number Package Number
Package Description
CD4047BCM
M14A
14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150” Narrow
14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300” Wide
CD4047BCN
N14A
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.
© 1999 Fairchild Semiconductor Corporation
DS005969.prf
www.fairchildsemi.com