Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Integrated Circuits (ICs) > Logic > Shift Registers

Nexperia USA Inc. HEF4021BT/C4J

Name: HEF4021BT/C4J
Brand: Nexperia USA Inc.
SKU: HEF4021BT/C4J
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: HEF4021BT/C4J

Manufacturer:: Nexperia USA Inc.

Category:: Shift Registers

Package:: 16-SOIC (0.154", 3.90mm Width)

Datasheet:: HEF4021BT/C4J.pdf

Description:: HEF4021BT - Parallel In Serial O

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:25,000

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

HEF4021BT/C4J from NXP Semiconductors is an 8-stage static shift register IC with parallel load and serial output, operating over 3–15 V supply, featuring CMOS logic compatibility, 100 µA typical quiescent current, and -40°C to +85°C industrial temperature range - used in LED display drivers and digital control sequencers.

For engineers reviewing the HEF4021BT/C4J datasheet, HEF4021BT/C4J pinout, HEF4021BT/C4J application, or HEF4021BT/C4J equivalent, key selection factors include parallel-load timing, serial-output propagation delay (120 ns max at 5 V), static latch retention, and compatibility with TTL/CMOS logic families in legacy control systems.

Technical Context

This device implements a synchronous 8-bit parallel-in/serial-out shift register using static CMOS circuitry, supporting both clocked parallel loading and edge-triggered serial shifting. It includes independent asynchronous master reset (MR) and clock enable (CE) controls, enabling precise sequencing in state-machine and data-conversion interfaces.

The internal architecture retains data during clock stoppage without refresh, and its dual-clock operation (CP and PL) allows independent control of load and shift phases - critical for buffered data transfer in microcontroller peripheral expansion and industrial I/O modules.

Key Specifications

Parameter	Value and Actual Design Meaning
Function	8-bit parallel-load static shift register with serial output
Supply Voltage	3 V to 15 V - supports direct interface with 5 V TTL and 3.3 V/5 V/12 V logic domains
Propagation Delay	120 ns max (CP to Q₇, V_DD = 5 V) - enables reliable 8 MHz serial clock operation
Quiescent Current	100 µA typical (V_DD = 5 V) - suitable for low-power battery-backed control registers
Operating Temp	-40°C to +85°C - qualified for industrial automation and outdoor instrumentation
Input Logic	CMOS-compatible inputs with TTL-level thresholds - ensures robust noise margin in mixed-signal PCBs

Pinout & Package

HEF4021BT/C4J is housed in a 16-pin SOIC (Small Outline Integrated Circuit) package with standard 1.27 mm pitch and gull-wing leads.

Pin/Terminal	Circuit Role	Design Meaning
V_DD	Positive supply	Connects to main logic rail (3–15 V); decoupling capacitor required near pin
V_SS	Ground reference	Common return path for all inputs, outputs, and internal logic
PL	Parallel load control	Active-HIGH synchronous load signal; latches D0–D7 on rising CP edge when PL = HIGH
CP	Shift clock input	Rising-edge triggered; advances data one position toward Q₇ output
MR	Master reset	Asynchronous active-LOW; forces all internal stages and Q₇ to logic LOW
D0–D7	Parallel data inputs	8-bit parallel data bus; sampled on PL-active CP edge
Q₇	Serial output	MSB-serial output; shifts out LSB-first after 8 clocks following load

Key Features

Feature	Design Value
Static operation	No clock required to retain data - eliminates need for continuous clocking in standby states
Independent PL and CP	Enables pipelined load-and-shift sequences without data corruption or timing overlap
Asynchronous MR	Allows immediate system-wide reset independent of clock phase or load state
Wide V_DD range	Single part replaces multiple voltage-specific shift registers across 3.3 V, 5 V, and 12 V designs

Applications

LED Display Controller

Industrial I/O Expander

Use Scenario: Driving 8-segment common-cathode LED displays via microcontroller GPIO expansion.

IC Role / Device Role / Timing Role: Serial-to-parallel data converter that buffers and sequences digit segments under CPU command.

Use Value: Reduces MCU pin count by 8 while maintaining static segment illumination without flicker.

Use Scenario: Adding isolated digital input channels to PLC backplanes with limited native I/O.

IC Role / Device Role / Timing Role: Parallel-input shift register capturing status bits from opto-isolated field sensors.

Use Value: Enables synchronized sampling of 8 remote switch or limit-switch signals per cycle.

Legacy Bus Interface

Test Equipment Sequencer

Use Scenario: Interfacing Z80 or 8085-based systems with modern peripherals via parallel data latching.

IC Role / Device Role / Timing Role: Synchronous data capture register aligned to CPU address strobes and clock edges.

Use Value: Provides deterministic setup/hold timing for 8-bit data transfers without external timing logic.

Use Scenario: Controlling stimulus timing in automated test fixtures for PCB functional verification.

IC Role / Device Role / Timing Role: Programmable pattern generator delivering precise 8-bit stimulus vectors on demand.

Use Value: Supports repeatable, clock-aligned test sequences with zero software overhead during execution.

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit parallel-load shift register applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
CD4021BE	Same function but PDIP package; higher propagation delay (200 ns @ 5 V)	Preferred for through-hole prototyping; less suitable for high-speed or space-constrained layouts	Select CD4021BE only for breadboard evaluation or legacy repair where SOIC footprint is incompatible
74HC165	8-bit parallel-load shift register with complementary serial output (Q and Q̅); no MR pin	Used in bidirectional data paths; lacks asynchronous reset for safety-critical reset-on-fault scenarios	Choose 74HC165 when dual-output signaling or HC-speed (20 ns @ 5 V) is required, and MR is not needed

Compared with CD4021BE and 74HC165, HEF4021BT/C4J offers optimal balance of SOIC packaging, industrial temperature rating, and integrated master reset - making it preferred for production-grade embedded controllers where reliability and board space matter.

Availability

HEF4021BT/C4J is available at Aetrix Electronics and suitable for LED display drivers, industrial I/O expanders, and legacy bus interface modules requiring stable component supply and long-term industrial qualification.

Supply support for HEF4021BT/C4J includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

HEF4021BT/C4J belongs to NXP's legacy HEF4000 series of CMOS logic ICs, designed specifically for robust, low-power digital control functions in industrial and instrumentation environments.

FAQ

What is the maximum clock frequency supported by HEF4021BT/C4J?

The HEF4021BT/C4J supports up to 8 MHz serial clock operation at V_DD = 5 V, based on its 120 ns maximum propagation delay from CP to Q₇. At 10 V, delay reduces to 60 ns, allowing up to 12 MHz operation. Frequency is limited by worst-case setup/hold timing of parallel load inputs relative to CP.

Does HEF4021BT/C4J require external pull-up or pull-down resistors on its inputs?

No - all inputs (PL, CP, MR, D0–D7) have built-in CMOS input structures with high impedance and defined logic thresholds. External resistors are unnecessary unless interfacing with open-collector sources or long traces requiring termination for noise immunity.

Can HEF4021BT/C4J be used in place of a 74LS165 in existing designs?

Yes, with voltage and timing validation: HEF4021BT/C4J operates at 3–15 V vs. 74LS165's fixed 5 V, and has slower propagation but lower power. Pin mapping differs - PL replaces SH/LD, and MR replaces CLR. Level-shifting may be needed for 5 V-only systems.

Is there a lead-free and RoHS-compliant version of HEF4021BT/C4J?

Yes - HEF4021BT/C4J is manufactured in accordance with RoHS Directive 2011/65/EU and is lead-free. The "T" suffix denotes tape-and-reel packaging, and the "C4J" variant code confirms compliance with JEDEC J-STD-020 moisture sensitivity level 3 and halogen-free epoxy molding compound.

HEF4021BT/C4J Specifications

Product attributes: Attribute value

Manufacturer:: Nexperia USA Inc.

Series:: Shift Register

Package/Case:: 16-SOIC (0.154", 3.90mm Width)

Packaging:: Bulk

Product Status:: Active

Logic Type:: -

Output Type:: Push-Pull

Number of Elements:: 1

Number of Bits per Element:: 8

Function:: Parallel or Serial to Serial

Voltage - Supply:: 3V ~ 15V

Operating Temperature:: -40°C ~ 125°C

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 16-SO

HEF4021BT/C4J FAQ

1.How can I place an order for HEF4021BT/C4J through Aetrix?

Please submit a Request for Quotation (RFQ) for HEF4021BT/C4J on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for HEF4021BT/C4J reliable?

The price and inventory of HEF4021BT/C4J are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for HEF4021BT/C4J is usually 5 days.

3.What payment methods are accepted for HEF4021BT/C4J?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for HEF4021BT/C4J transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for HEF4021BT/C4J?

HEF4021BT/C4J orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your HEF4021BT/C4J order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for HEF4021BT/C4J?

For technical support, including HEF4021BT/C4J datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your HEF4021BT/C4J requirements.

6.How does Aetrix verify that HEF4021BT/C4J is sourced from the original manufacturer or authorized distributors?

All HEF4021BT/C4J products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that HEF4021BT/C4J meets industry standards.

7.What is the process for return or replacement of HEF4021BT/C4J?

All HEF4021BT/C4J units undergo pre-shipment inspection (PSI). If there is an issue with HEF4021BT/C4J, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The HEF4021BT/C4J part is unused and in its original packaging.

Return procedure for HEF4021BT/C4J:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…

2026-08-11 LDO Regulator: Dropout Voltage, Noise, PSRR and Power Dissipation

LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…

2026-08-06 Conditional Access Module: CAM, CI/CI+ and DVB Security

Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…

2026-08-03 Electronic Component Obsolescence: EOL Risks, Replacement Options and Last-Time Buy Strategy

Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.

2026-07-29 18650 Battery: Voltage, Capacity, Charging and Pack Design

18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…

2026-07-27 Hall Effect Sensor: Working Principle, Types, Circuits and Applications

Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…

2026-07-20 Product Change Notification (PCN) in Electronic Components: Meaning and Supply Chain Response

Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…

2026-07-19 Blend Door Actuator: Symptoms, Location, Reset and Replacement Guide

A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…