CD74HC4538-Q1 Datasheet, PDF (1/16 Pages) Texas Instruments – HIGH-SPEED CMOS LOGIC DUAL RETRIGGERABLE PRECISION MONOSTABLE MULTIVIBRATOR

CD74HC4538-Q1
HIGH-SPEED CMOS LOGIC DUAL RETRIGGERABLE
PRECISION MONOSTABLE MULTIVIBRATOR
SCLS595A − NOVEMBER 2004 − REVISED APRIL 2008
D Qualified for Automotive Applications
D Balanced Propagation Delay and Transition
D Retriggerable/Resettable Capability
D Trigger and Reset Propagation Delays
Independent of R_X, C_X
D Triggering From the Leading or Trailing
Edge
D Q and Q Buffered Outputs Available
Times
D Significant Power Reduction Compared to
LSTTL Logic ICs
D V_CC Voltage = 2 V to 6 V
D High Noise Immunity N_IL or N_IH = 30% of
V_CC, V_CC = 5 V
D Separate Resets
D Wide Range of Output Pulse Widths
D Schmitt-Trigger Input on A and B Inputs
D Retrigger Time Is Independent of C_X
D Fanout (Over Temperature Range)
− Standard Outputs . . . 10 LSTTL Loads
− Bus Driver Outputs . . . 15 LSTTL Loads
M OR PW PACKAGE
(TOP VIEW)
1C_X 1
1R_XC_X 2
1R 3
1A 4
1B 5
16 V_CC
15 2C_X
14 2R_XC_X
13 2R
12 2A
description/ordering information
1Q 6
1Q 7
11 2B
10 2Q
The CD74HC4538 is a dual retriggerable/resettable
GND 8
9 2Q
precision monostable multivibrator for fixed-voltage
timing applications. An external resistor (R_X) and
external capacitor (C_X) control the timing and accuracy for the circuit. Adjustment of R_X and C_X provides a wide
range of output pulse widths from the Q and Q terminals. The propagation delay from trigger input-to-output
transition and the propagation delay from reset input-to-output transition are independent of R_X and C_X.
Leading-edge triggering (A) and trailing-edge triggering (B) inputs are provided for triggering from either edge
of the input pulse. An unused A input should be tied to GND and an unused B input should be tied to V_CC. On
power up, the IC is reset. Unused resets and sections must be terminated. In normal operation, the circuit
retriggers on the application of each new trigger pulse. To operate in the nontriggerable mode, Q is connected
to B when leading-edge triggering (A) is used, or Q is connected to A when trailing-edge triggering (B) is used.
The period (τ) can be calculated from τ = (0.7) R_X, C_X; R_MIN is 5 kΩ. C_MIN is 0 pF.
ORDERING INFORMATION^{
T_A
PACKAGE^‡
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
−40°C to 125°C
SOIC − M
Tape and reel
TSSOP − PW Tape and reel
CD74HC4538QM96Q1 HC4538M
CD74HC4538QPWRQ1 HC4538M
† _{For the most current package and ordering information, see the Package Option Addendum at the}
end of this document, or see the TI web site at http://www.ti.com.
‡ _{Package drawings, thermal data, and symbolization are available at http://www.ti.com/packaging.}
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
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testing of all parameters.
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