TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic
Dual Retriggerable Monostable Multivibrator
The TC74HC423A is a high speed CMOS MONOSTABLE
MULTIVIBRATOR fabricated with silicon gate C2MOS
It achieves the high speed operation similar to equivalent
LSTTL while maintaining the CMOS low power dissipation.
There are two trigger inputs, A input (negative edge), and B
input (positive edge). These inputs are valid for a slow rise/fall
time signal (tr = tf = 1 s) as they are schmitt trigger inputs.
After triggering, the output stays in a MONOSTABLE state for
a time period determined by the external resistor and capacitor
(Rx, Cx ). A low level at the CLR input breaks this state. In the
MONOSTABLE state, if a new trigger is applied, it extends the
MONOSTABLE period (retrigger mode).
Limitations for Cx and Rx are:
External capacitor, Cx: No limit
External resistor, Rx: VCC = 2.0 V more than 5 kΩ
VCC ≥ 3.0 V more than 1 kΩ
All inputs are equipped with protection circuits against static
discharge or transient excess voltage.
• High speed: tpd = 25 ns (typ.) at VCC = 5 V
• Low power dissipation
Standby state: ICC = 4 μA (max) at Ta = 25°C
Active state: ICC = 700 μA (max) at VCC = 5 V
• High noise immunity: VNIH = VNIL = 28% VCC (min)
• Output drive capability: 10 LSTTL loads
• Symmetrical output impedance: |IOH| = IOL = 4 mA (min)
• Balanced propagation delays: tpLH ∼− tpHL
• Wide operating voltage range: VCC (opr) = 2 to 6 V
• Pin and function compatible with 74LS423
: 1.00 g (typ.)
: 0.18 g (typ.)
Note: In the case of using only one circuit, CLR should be tied to GND, Rx/Cx･Cx･Q･ Q should be tied to
OPEN, the other inputs should be tied to VCC or GND.
Start of commercial production