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STMicroelectronics HCF4021BEY
- Part No.:
- HCF4021BEY
- Manufacturer:
- STMicroelectronics
- Category:
- Shift Registers
- Package:
- 16-DIP (0.300", 7.62mm)
- Datasheet:
-
HCF4021BEY.pdf
- Description:
- IC SHIFT REGISTER 8STAGE 16-DIP
- Quantity:
- Payment:
- Shipping:
Inventory:2,266
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Product details
Overview
HCF4021BEY from STMicroelectronics is an 8-stage asynchronous parallel-input/synchronous serial-in/serial-out static shift register in PDIP-16 package, operating up to 12 MHz (typ.) at 10 V supply, with independent parallel jam inputs per stage, buffered Q6/Q7/Q8 outputs, and -55 °C to +125 °C temperature range.
For engineers reviewing the HCF4021BEY datasheet, HCF4021BEY pinout, HCF4021BEY application, or HCF4021BEY equivalent, this device supports mixed-mode data loading (asynchronous parallel jam vs. synchronous serial shift), offers rail-to-rail output swing across 3–20 V supply, and enables cascaded register expansion in industrial control and legacy digital logic systems.
Technical Context
The HCF4021BEY implements eight D-type master-slave flip-flops with common clock and dual-mode control via a single PARALLEL/SERIAL input. Serial entry is edge-triggered on the rising clock edge, while parallel entry forces internal clock gating for asynchronous load timing.
It features static CMOS operation with quiescent current specified up to 20 V, 100 nA max input leakage at 18 V, and ESD ratings of 1 kV (CDM), 2 kV (HBM), and 200 V (MM). Output drive capability is ±1.36 mA (IOH/IOL) at 5 V, scaling with supply voltage.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Function | 8-stage static shift register with selectable parallel-load or serial-shift mode |
| Max Clock Frequency | 12 MHz typical at VDD = 10 V - defines maximum data throughput in serial mode |
| Supply Voltage Range | 3 V to 20 V - supports wide-battery and industrial rail compatibility |
| Output Drive | ±1.36 mA at VDD = 5 V - sufficient to drive TTL loads or subsequent CMOS stages directly |
| Propagation Delay | 320 ns max at VDD = 5 V - determines minimum clock period and setup margin in synchronous designs |
| Input Leakage | ±100 nA max at VDD = 18 V, TA = 25 °C - ensures low power consumption and stable DC bias in high-impedance interfaces |
| Operating Temp | -55 °C to +125 °C - qualified for extended industrial and under-hood automotive environments |
Pinout & Package
Packaged in 16-pin plastic dual in-line package (PDIP-16), 0.25-inch width, with through-hole mounting and industry-standard pin spacing (2.54 mm pitch).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 3, 4, 13, 14, 15, 1 | PI-1 to PI-8 | Asynchronous parallel data inputs - enable immediate register loading without clock dependency |
| 11 | SERIAL IN | Serial data input - synchronized to rising clock edge during serial-shift mode |
| 9 | PARALLEL/SERIAL CONTROL | Mode select: high = parallel jam, low = serial shift - controls internal gating and clock forcing |
| 10 | CLOCK | Positive-edge-triggered master clock - drives all internal flip-flops and output latching |
| 2, 3, 12 | Q6, Q7, Q8 | Buffered stage outputs - provide fan-out capability and isolation from internal node loading |
| 8 | VSS | Negative supply reference - must be connected to system ground or lowest potential rail |
| 16 | VDD | Positive supply input - powers entire register; supports 3–20 V operation |
Key Features
| Feature | Design Value |
|---|---|
| Fully static CMOS operation | Zero dynamic power in hold state; eliminates need for minimum clock frequency |
| Asynchronous parallel load with jam inputs | Enables immediate register update independent of clock phase - critical for reset or preset functions |
| Three buffered output taps (Q6, Q7, Q8) | Reduces loading on internal nodes and supports multi-point fan-out without signal degradation |
| 100% tested quiescent current | Guarantees low standby power across full temperature and voltage range - essential for battery-backed systems |
| ESD robustness (CDM 1 kV, HBM 2 kV) | Supports handling and assembly in non-ESD-controlled environments without additional protection circuitry |
Applications
| Industrial PLC I/O Expansion | Legacy Computer Bus Interface |
|---|---|
|
Use Scenario: Expanding discrete I/O points on programmable logic controller backplanes using parallel data from microcontroller GPIO ports. IC Role / Device Role / Timing Role: Parallel-to-serial converter and output latch - accepts 8-bit parallel commands and shifts them out synchronously to reduce bus pin count. Use Value: Enables 8-bit parallel data transfer at up to 12 MHz, reducing microcontroller GPIO usage while maintaining deterministic timing via clocked serial output. |
Use Scenario: Interfacing 8-bit microprocessors (e.g., Z80, 8085) with peripheral devices requiring serialized control words over shared data buses. IC Role / Device Role / Timing Role: Synchronous serial register - converts processor write cycles into timed serial bit streams for peripheral configuration registers. Use Value: Provides precise clock-aligned serial output with guaranteed 320 ns max propagation delay, ensuring reliable timing margins in bus-critical legacy systems. |
| Automotive Body Control Module | Digital Test Equipment Pattern Generator |
|
Use Scenario: Driving multiplexed LED arrays or relay banks in vehicle body electronics where wide supply tolerance and extended temperature operation are required. IC Role / Device Role / Timing Role: High-voltage tolerant shift register - accepts 12 V nominal supply and delivers buffered outputs capable of sinking 2.4 mA at 15 V. Use Value: Operates reliably from -55 °C to +125 °C and supports 3–20 V supply, eliminating need for external level-shifting or regulation in 12 V automotive systems. |
Use Scenario: Generating repeatable digital stimulus patterns for IC functional testing using microcontroller-controlled parallel load and clocked serial output. IC Role / Device Role / Timing Role: Programmable pattern sequencer - parallel jam inputs allow instant loading of test vectors; serial output provides deterministic bit-stream timing. Use Value: Asynchronous parallel load enables zero-latency vector updates between test cycles, while 12 MHz max clock supports high-speed pattern generation up to 96 Mbps (8 bits × 12 MHz). |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 8-bit static shift register applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CD4021BE | Same logic function and pinout, but lower ESD rating (HBM 500 V vs. 2 kV) and no 100% quiescent current test | Not qualified for extended temperature (-55 °C to +125 °C) or high-reliability industrial use | Select when cost sensitivity outweighs ESD robustness and extended temp requirements |
| MC14021BCP | Identical architecture but higher propagation delay (500 ns max at 5 V) and narrower supply range (3–18 V) | Limited to commercial temperature range (-40 °C to +85 °C); unsuitable for under-hood or harsh environments | Choose only for legacy designs where MC14xxx family compatibility is mandatory |
Compared with CD4021BE and MC14021BCP, the HCF4021BEY delivers superior ESD immunity, full -55 °C to +125 °C qualification, and tighter propagation delay specs - making it the preferred choice for new industrial and automotive designs requiring long-term reliability and wide supply tolerance.
Availability
HCF4021BEY is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, legacy computer bus interface, and automotive body control modules requiring stable component supply across extended temperature and voltage ranges.
Supply support for HCF4021BEY 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for industrial, automotive, and consumer markets.
The HCF4021BEY belongs to ST's high-reliability HCMOS logic family, engineered for robust operation in extended temperature and wide-supply environments where legacy CMOS compatibility and static power efficiency are critical.
FAQ
Can HCF4021BEY operate with a 3.3 V supply?
Yes, HCF4021BEY supports 3 V minimum supply voltage per its recommended operating conditions. At 3.3 V, output drive strength reduces to approximately ±0.5 mA, and maximum clock frequency drops to ~2 MHz. Logic thresholds scale with VDD, so interfacing with 3.3 V microcontrollers requires verifying VIH/VIL margins using the datasheet's 3 V test conditions.
What is the purpose of the PARALLEL/SERIAL CONTROL pin being active-high for parallel load?
The PARALLEL/SERIAL CONTROL pin (Pin 9) is active-high to enable asynchronous parallel jam loading. When high, it forces internal clock gating to capture parallel inputs on the next rising clock edge - ensuring deterministic alignment of parallel data with the system clock domain while avoiding metastability in mixed-mode operation.
How does the HCF4021BEY handle cascading multiple devices for longer shift registers?
HCF4021BEY supports cascading via Q8 output to SERIAL IN of the next device. The datasheet confirms register expansion is permitted, and propagation delay (max 320 ns at 5 V) and transition time (max 200 ns) ensure timing integrity across chains. No external logic is needed - only clock and control lines require fan-out buffering for >3 devices.
Is the HCF4021BEY RoHS-compliant and lead-free?
Yes, HCF4021BEY is manufactured in ST's ECOPACK®-compliant PDIP-16 package, meeting RoHS Directive 2011/65/EU and REACH SVHC requirements. The device carries the "ECOPACK2" designation, indicating lead-free terminations and halogen-free molding compound, with full compliance documentation available on ST's official product page.
HCF4021BEY Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- 4000B
- Package/Case:
- 16-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Logic Type:
- Shift Register
- Output Type:
- Push-Pull
- Number of Elements:
- 1
- Number of Bits per Element:
- 8
- Function:
- Parallel or Serial to Serial
- Voltage - Supply:
- 3V ~ 20V
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 16-DIP
HCF4021BEY FAQ
1.How can I place an order for HCF4021BEY through Aetrix?
Please submit a Request for Quotation (RFQ) for HCF4021BEY 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 HCF4021BEY reliable?
The price and inventory of HCF4021BEY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for HCF4021BEY is usually 5 days.
3.What payment methods are accepted for HCF4021BEY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for HCF4021BEY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for HCF4021BEY?
HCF4021BEY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your HCF4021BEY 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 HCF4021BEY?
For technical support, including HCF4021BEY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your HCF4021BEY requirements.
6.How does Aetrix verify that HCF4021BEY is sourced from the original manufacturer or authorized distributors?
All HCF4021BEY 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 HCF4021BEY meets industry standards.
7.What is the process for return or replacement of HCF4021BEY?
All HCF4021BEY units undergo pre-shipment inspection (PSI). If there is an issue with HCF4021BEY, 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 HCF4021BEY part is unused and in its original packaging.
Return procedure for HCF4021BEY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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