My Inquiry
My Account
Texas Instruments CD74HC257E
- Part No.:
- CD74HC257E
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 16-DIP (0.300", 7.62mm)
- Datasheet:
-
CD74HC257E.pdf
- Description:
- IC MULTIPLEXER 4 X 2:1 16DIP
- Quantity:
- Payment:
- Shipping:
Inventory:150
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
CD74HC257E from Texas Instruments is a quad 2-input multiplexer with three-state non-inverting outputs, designed for data routing in digital logic systems. It features 12ns typical propagation delay at 5V/15pF, operates from 2V to 6V, and supports -55°C to +125°C industrial/military temperature range. Its active-low Output Enable (OE) allows bus sharing in multi-device systems.
For engineers reviewing the CD74HC257E datasheet, CD74HC257E pinout, CD74HC257E application, or CD74HC257E equivalent, key selection criteria include its HC-family CMOS logic compatibility, 16-pin PDIP package, three-state output control, and guaranteed operation across extended temperature extremes.
Technical Context
The CD74HC257E implements four identical 2:1 multiplexer circuits sharing one Select (S) input and one active-low Output Enable (OE) signal. Each channel routes either I0 or I1 to Y based on S state, with outputs entering high-impedance when OE is HIGH.
Its HC logic family ensures rail-to-rail voltage transfer, 30% noise immunity (NIL/NIH), and low quiescent current (≤160µA over full temperature range). Propagation delays are balanced between tPLH and tPHL, and transition times remain consistent across VCC = 2–6V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | High-speed CMOS (HC), compatible with 2V–6V supply |
| Propagation Delay (tPLH/tPHL) | 12ns typical at VCC = 5V, CL = 15pF - enables fast synchronous data selection |
| Operating Temperature | -55°C to +125°C - qualified for military, aerospace, and harsh-environment industrial use |
| Output Type | Three-state non-inverting - allows direct connection to shared data buses without contention |
| Input Noise Immunity | NIL = NIH = 30% of VCC at 5V - robust against supply and coupling noise |
| Quiescent Current (ICC) | ≤160µA max over full temperature range - supports low-power system standby modes |
| Input Capacitance (CI) | 10pF - minimizes loading on driving logic stages |
Pinout & Package
CD74HC257E is supplied in a 16-lead plastic dual in-line package (PDIP), with standard through-hole mounting and 0.3-inch body width. Pin 1 is located at the top-left corner with notch or dot marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | 1I0 | Data input 0 for channel 1 |
| 2 | 1I1 | Data input 1 for channel 1 |
| 3 | 1Y | Three-state output for channel 1 |
| 4 | 2I0 | Data input 0 for channel 2 |
| 5 | 2I1 | Data input 1 for channel 2 |
| 6 | GND | Ground reference for all logic and power |
| 7 | 2Y | Three-state output for channel 2 |
| 8 | VCC | Positive supply (2V–6V) |
| 9 | 3Y | Three-state output for channel 3 |
| 10 | 3I1 | Data input 1 for channel 3 |
| 11 | 3I0 | Data input 0 for channel 3 |
| 12 | 4Y | Three-state output for channel 4 |
| 13 | 4I1 | Data input 1 for channel 4 |
| 14 | 4I0 | Data input 0 for channel 4 |
| 15 | S | Common select input (0 → I0, 1 → I1) |
| 16 | OE | Active-low output enable (HIGH = high-Z) |
Key Features
| Feature | Design Value |
|---|---|
| Quad 2:1 multiplexing with shared control | Reduces component count vs. discrete gates; simplifies PCB layout for parallel data routing |
| Three-state outputs with common OE | Enables time-multiplexed bus access across multiple CD74HC257E devices on same data path |
| Balanced propagation delay & transition times | Minimizes skew between channels and ensures clean timing margins in synchronous designs |
| Wide VCC range (2V–6V) | Supports mixed-voltage system interfacing (e.g., 3.3V logic controlling 5V peripherals) |
| High noise immunity (30% of VCC) | Improves reliability in electrically noisy environments such as motor drives or power supplies |
Applications
| Industrial PLC I/O Expansion | Aerospace Avionics Data Routing |
|---|---|
Use Scenario: Expanding discrete input monitoring across multiple sensor banks using shared microcontroller GPIO lines. IC Role / Device Role / Timing Role: CD74HC257E selects among eight sensor inputs (four pairs) under microcontroller S/OE control, feeding consolidated data to a single ADC input. Use Value: Reduces required MCU pins by 75% while maintaining deterministic 12ns selection latency and full -55°C to +125°C operation. | Use Scenario: Routing telemetry signals from redundant flight sensors to central processing units in fly-by-wire systems. IC Role / Device Role / Timing Role: CD74HC257E acts as a fail-safe signal selector, switching between primary and backup sensor streams based on health status flags. Use Value: Enables hardware-level redundancy arbitration with sub-15ns worst-case propagation and guaranteed operation at extreme temperatures. |
| Test Equipment Signal Switching | Military Radio Baseband Processing |
Use Scenario: Configurable signal path selection in automated test equipment (ATE) for DUT interface adaptation. IC Role / Device Role / Timing Role: CD74HC257E routes calibration reference signals or DUT outputs to measurement circuitry under FPGA control. Use Value: Provides repeatable, low-skew switching (≤45ns max delay over temp) with no external pull-ups needed due to buffered inputs. | Use Scenario: Dynamic reconfiguration of baseband filter paths in software-defined radios operating in field-deployed enclosures. IC Role / Device Role / Timing Role: CD74HC257E selects between analog front-end filter banks during mode transitions (e.g., HF/VHF/UHF). Use Value: Delivers radiation-tolerant, wide-temp performance with <10pF input capacitance to preserve signal integrity in RF-adjacent digital sections. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad 2-input multiplexer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74HC257N | Same logic function, pinout, and electrical specs; manufactured by TI but catalog-grade (non-military temp range: -40°C to +85°C) | Limited to commercial/industrial ambient conditions; not rated for -55°C startup or +125°C sustained operation | Select SN74HC257N only if full military temperature range is unnecessary and cost optimization is prioritized. |
| CD74HCT257E | Same pinout and function, but HCT logic family: 4.5V–5.5V only, LSTTL-input compatible (VIH=2V min, VIL=0.8V max) | Required when interfacing directly with legacy 5V TTL outputs; incompatible with 3.3V or 2V logic without level translation | Choose CD74HCT257E when integrating into existing 5V TTL systems where input voltage thresholds must match legacy drivers. |
Compared with SN74HC257N, CD74HC257E offers extended temperature qualification critical for aerospace and defense; versus CD74HCT257E, it provides broader supply flexibility and superior noise immunity at the cost of TTL input compatibility.
Availability
CD74HC257E is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, aerospace avionics data routing, and military radio baseband processing requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for CD74HC257E 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
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions with over 90 years of innovation in high-reliability components.
The CD74HC257E belongs to TI's CD74HC high-speed CMOS logic family, engineered for robust performance in military, aerospace, and industrial applications demanding wide temperature operation and noise resilience.
FAQ
What is the maximum supply voltage rating for CD74HC257E?
The absolute maximum DC supply voltage for CD74HC257E is 7V, but recommended operational range is 2V to 6V per the datasheet. Operating continuously above 6V risks permanent damage, while operation below 2V may cause unreliable logic thresholds. The CD74HC257E achieves optimal speed-power tradeoff at 4.5V–5.5V, delivering 12ns typical propagation delay at 5V with 15pF load.
Does CD74HC257E support 3.3V logic systems?
Yes, CD74HC257E fully supports 3.3V operation within its 2V–6V supply range. At VCC = 3.3V, it maintains valid HC logic thresholds (VIH ≥ 2.0V, VIL ≤ 1.35V), delivers ≤40ns max propagation delay, and draws <100µA ICC across temperature. Its 30% noise margin and 10pF input capacitance ensure reliable interfacing with modern 3.3V microcontrollers and FPGAs without level shifters.
How does the Output Enable (OE) pin function on CD74HC257E?
The OE pin on CD74HC257E is active-low: when HIGH, all four outputs (1Y–4Y) enter high-impedance state regardless of S or input states; when LOW, outputs reflect selected inputs per truth table. This enables bus-sharing architectures where multiple CD74HC257E devices drive the same line under centralized OE control, eliminating contention without external isolation logic.
Can CD74HC257E replace CD74HCT257E in an existing design?
CD74HC257E can replace CD74HCT257E only if the system operates within 2V–6V and does not rely on LSTTL input compatibility. CD74HC257E has higher VIH (1.5V min at 2V, 3.15V at 4.5V) than CD74HCT257E (2.0V min across 4.5V–5.5V), so legacy 5V TTL outputs may not reliably drive it. Verify input voltage levels and timing margins before substitution; no PCB changes are needed since both share identical 16-pin PDIP footprint and pinout.
What is the thermal resistance (θJA) of the CD74HC257E PDIP package?
The junction-to-ambient thermal resistance (θJA) for CD74HC257E in its 16-lead PDIP package is 67°C/W under typical JEDEC-standard board conditions. This value assumes a two-layer board with 1 in² copper pour per side. At maximum rated power dissipation (≈15mW typical), junction temperature rise remains under 1°C - well within safe limits even at +125°C ambient, confirming suitability for convection-cooled military and industrial enclosures.
CD74HC257E Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74HC
- Package/Case:
- 16-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- Multiplexer
- Circuit:
- 4 x 2:1
- Independent Circuits:
- 1
- Current - Output High, Low:
- 7.8mA, 7.8mA
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 2V ~ 6V
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 16-PDIP
CD74HC257E FAQ
1.How can I place an order for CD74HC257E through Aetrix?
Please submit a Request for Quotation (RFQ) for CD74HC257E 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 CD74HC257E reliable?
The price and inventory of CD74HC257E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for CD74HC257E is usually 5 days.
3.What payment methods are accepted for CD74HC257E?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for CD74HC257E transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for CD74HC257E?
CD74HC257E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your CD74HC257E 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 CD74HC257E?
For technical support, including CD74HC257E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your CD74HC257E requirements.
6.How does Aetrix verify that CD74HC257E is sourced from the original manufacturer or authorized distributors?
All CD74HC257E 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 CD74HC257E meets industry standards.
7.What is the process for return or replacement of CD74HC257E?
All CD74HC257E units undergo pre-shipment inspection (PSI). If there is an issue with CD74HC257E, 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 CD74HC257E part is unused and in its original packaging.
Return procedure for CD74HC257E:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
CD74HC257E Tags
-
SN74HC138DR
Texas Instruments
-
TC7SB3157CFU,LF(CT
Toshiba Semiconductor and Storage
-
74CBTLV3257PW,118
Nexperia USA Inc.
-
SN74CBTLV3257PWR
Texas Instruments
-
74CBTLV3257GUX
Nexperia USA Inc.
-
74HC154BQ,118
Nexperia USA Inc.
-
P3S0200GMX
NXP USA Inc.
-
SN74CB3Q3245PWR
Texas Instruments
-
SN74CB3Q3257RGYR
Texas Instruments
-
TCA9543APWR
Texas Instruments
-
TCA9546APWR
Texas Instruments
-
SN74HC138N
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
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…
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…
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…
