TC74HC4538AP/AF/AFT
TOSHIBA CMOS Digital Integrated Circuit
Silicon Monolithic
TC74HC4538AP, TC74HC4538AF, TC74HC4538AFT
Dual Retriggerable Monostable Multivibrator
The TC74HC4538A is a high speed CMOS MONOSTABLE
MULTIVIBRATOR fabricated with silicon gate C2MOS
technology.
It achieves the high speed operation similar to equivalent
LSTTL while maintaining the CMOS low power dissipation.
There are two trigger inputs, A input (positive edge input), and
B input (negative edge input). 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
the time period determined by the external resistor and capacitor
(RX, CX). A low level at CD input breaks this STABLE STATE.
In the MONOSTABLE state, if a new trigger is applied, it makes
the MONOSTABLE period longer (retrigger mode).
Limitations for CX and RX are as follows:
External capacitor CX ........... No limitation
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.
TC74HC4538AP
TC74HC4538AF
TC74HC4538AFT
Features (Note)
•
High speed: tpd = 25 ns (typ.) at VCC = 5 V
•
Low power dissipation
Stand by state: ICC = 4 μA (max) at Ta = 25°C
Active state: ICC = 300 μA (max) at Ta = 25°C
•
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 V to 6 V
•
Pin and function compatible with 4538B
Weight
DIP16-P-300-2.54A
SOP16-P-300.1.27A
TSSOP16-P-0044-0.65A
: 1.00 g (typ.)
: 0.18 (typ.)
: 0.06 g (typ.
Note:
In the case of using only one circuit, CD should be
tied to GND, T1·T2·Q· Q should be tied to OPEN, the other
inputs should be tied to VCC or GND.
Start of commercial production
1987-11
1
2014-03-01