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74HC194D

4-bit bidirectional universal shift register

The 74HC194 is a 4-bit bidirectional universal shift register. The synchronous operation of the device is determined by the mode select inputs (S0, S1). In parallel load mode (S0 and S1 HIGH) data appearing on the D0 to D3 inputs, when S0 and S1 are HIGH, is transferred to the Q0 to Q3 outputs. When S0 is HIGH and S1 is LOW data is entered serially via DSL and shifted from left to right; when S0 is LOW and S1 is HIGH data is entered serially via DSR and shifted from right to left. DSR and DSL allow multistage shift right or shift left data transfers without interfering with parallel load operation. If both S0 and S1 are LOW, existing data is retained in a hold mode.

Mode select and data inputs are edge-triggered, responding only to the LOW-to-HIGH transition of the clock (CP). Therefore, the only timing restriction is that the mode control and selected data inputs must be stable one set-up time prior to the positive transition of the clock pulse. When LOW, the asynchronous master reset (MR) overrides all other input conditions and forces the Q outputs LOW.

Inputs include clamp diodes. This enables the use of current limiting resistors to interface inputs to voltages in excess of VCC.

This product has been discontinued, click here for discontinuation information and replacement parts.

Orderable parts

Type number Orderable part number Ordering code (12NC) Package Buy from distributors

Features and benefits

  • Complies with JEDEC standard no. 7A
  • Input levels:
    • For 74HC194: CMOS level
  • Shift-left and shift-right capability
  • Synchronous parallel and serial data transfer
  • Easily expanded for both serial and parallel operation
  • Asynchronous master reset
  • Hold ('do nothing') mode
  • ESD protection:
    • HBM JESD22-A114F exceeds 2000 V
    • MM JESD22-A115-A exceeds 200 V
  • Specified from -40 °C to +85 °C and -40 °C to +125 °C

Applications

  • Serial-to-parallel data conversion
  • Remote control holding register

Parametrics

Type numberProduct statusVCC (V)Logic switching levelsOutput drive capability (mA)tpd (ns)fmax (MHz)No of bitsPower dissipation considerationsTamb (°C)Rth(j-a) (K/W)Ψth(j-top) (K/W)Rth(j-c) (K/W)Package name
74HC194DEnd of life2.0 - 6.0CMOS± 5.2141024low-40~125783.236SO16

Package

All type numbers in the table below are discontinued. See the table Discontinuation information for more information.

Type numberOrderable part number, (Ordering code (12NC))StatusMarkingPackagePackage informationReflow-/Wave solderingPacking
74HC194D74HC194D,653
( 9337 140 90653 )
Discontinued / End-of-life74HC194D
SO16
(SOT109-1)
SOT109-1SO-SOJ-REFLOW
SO-SOJ-WAVE
Reel 13" Q1/T1 CECC
74HC194D,652
( 9337 140 90652 )
Discontinued / End-of-life74HC194DBulk Pack, CECC

Discontinuation information

Type numberOrderable part numberOrdering codeLast time buy dateLast time delivery dateReplacement productStatusComments
74HC194D74HC194D,6539337140906532021-06-302021-12-31No replacementFull withdrawal
74HC194D74HC194D,6529337140906522021-06-302021-12-31No replacementFull withdrawal

Quality, reliability & chemical content

All type numbers in the table below are discontinued. See the table Discontinuation information for more information.

Type numberOrderable part numberChemical contentRoHS / RHFMSLMSL leadfree
74HC194D74HC194D,65374HC194D11
74HC194D74HC194D,65274HC194D11
Quality and reliability disclaimer

Documentation (5)

File nameTitleTypeDate
74HC1944-bit bidirectional universal shift registerData sheet2017-03-17
AN11044Pin FMEA 74HC/74HCT familyApplication note2019-01-09
HCT_USER_GUIDEHC/T User GuideUser manual1997-10-31
SO-SOJ-REFLOWFootprint for reflow solderingReflow soldering2009-10-08
SO-SOJ-WAVEFootprint for wave solderingWave soldering2009-10-08

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