My Inquiry
My Account
Texas Instruments SNJ54ALS857JT
- Part No.:
- SNJ54ALS857JT
- Manufacturer:
- Texas Instruments
- Category:
- Signal Switches, Multiplexers, Decoders
- Package:
- 24-CDIP (0.300", 7.62mm)
- Datasheet:
-
SNJ54ALS857JT.pdf
- Description:
- HEX 2-TO-1 UNIVERSAL MULTIPLEXER
- Quantity:
- Payment:
- Shipping:
Inventory:2,250
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SNJ54ALS857JT from Texas Instruments is a military-grade hex 2-to-1 universal multiplexer with 3-state outputs, performing true/inverted data selection, AND masking (A•B), and zero-detection across six independent channels. It operates over –55°C to 125°C, features 12-mA low-level output drive, and supports bus interfacing via high-impedance outputs controlled by COMP/S0/S1. Used in legacy aerospace data routing and fault-tolerant control logic.
For engineers reviewing the SNJ54ALS857JT datasheet, SNJ54ALS857JT pinout, SNJ54ALS857JT application, or SNJ54ALS857JT equivalent, key selection criteria include its dual-mode operand selection (A/B), cascading capability for operand expansion, OPER=0 zero-detection flag, 3-state bus compatibility, and ceramic DIP (JT) package suitability for high-reliability mil-spec PCBs.
Technical Context
The SNJ54ALS857JT implements six identical 2-input multiplexing channels, each selectable between A or B inputs-or configured for logical AND (A•B) or clear mode-via S0/S1/COMP control lines. Its OPER=0 output asserts high only when all selected A or B inputs are low, enabling parallel zero detection without external logic.
All six Y outputs and the OPER=0 signal are 3-state capable, entering high-impedance when COMP, S0, and S1 are simultaneously high. The device uses bipolar ALS (Advanced Low-Power Schottky) technology, delivering propagation delays as low as 2 ns (typical) for A/B→Y paths at VCC = 4.5–5.5 V and CL = 50 pF.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Family | ALS (Advanced Low-Power Schottky) - balances speed (sub-30 ns max tpd) and power (ICC ≤ 36 mA active) for legacy TTL-compatible systems. |
| Operating Temperature | –55°C to 125°C - qualified per MIL-PRF-38535 for use in avionics, missile guidance, and space-qualified electronics. |
| IOL (Low-Level Output) | 12 mA - sufficient to directly drive multiple TTL inputs or terminate stubs on backplane buses without external buffers. |
| VOL (Output Low Voltage) | 0.25 V (max at IOL = 12 mA) - ensures robust noise margin (>0.7 V) against TTL VIH threshold of 2.0 V. |
| tpd (A/B → Y) | 27 ns (max at TA = 125°C) - enables synchronous operation up to ~15 MHz in critical timing paths with setup/hold compliance. |
| 3-State Enable Delay | ten = 37 ns (max), tdis = 45 ns (max) - defines minimum control-to-output assertion/retraction window for bus arbitration timing budgets. |
| Supply Voltage Range | 4.5 V to 5.5 V - compatible with regulated 5-V military power supplies; absolute max rating of 7 V prevents latch-up during transient overvoltage. |
Pinout & Package
Ceramic Dual-In-Line Package (CDIP), JT variant: 24-pin, 0.3-inch wide, hermetically sealable, MIL-STD-1835 GDIP3-T24 compliant, with glass-frit lid option for enhanced moisture resistance and long-term reliability in harsh environments.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 5, 6, 8, 9, 15, 16, 18, 19, 21, 22 | Data Inputs (1A–6B) | Twelve independent operand inputs - grouped as six A/B pairs; each pair feeds one multiplexer channel. |
| 4, 7, 10, 14, 17, 20 | 3-State Outputs (1Y–6Y) | Six buffered, tristatable outputs - driven low/high or placed in Hi-Z based on COMP/S0/S1 state. |
| 3, 23, 24 | Control Inputs (S0, S1, COMP) | Mode-select triple control: S0/S1 choose A/B/AND/Clear; COMP selects true (low) or complemented (high) output polarity. |
| 11 | Zero-Detection Flag (OPER = 0) | Open-collector–compatible active-high flag asserting only when all selected A or B inputs are logic low. |
| 12, 13 | Power (GND, VCC) | Single 5-V supply rail; dedicated ground pin minimizes switching noise coupling into analog or timing-sensitive subsystems. |
| 25–28 | No Connect (NC) | Four unconnected pins - electrically isolated; no internal bonding or circuitry; must remain floating per TI design. |
Key Features
| Feature | Design Value |
|---|---|
| Hex 2-to-1 Universal Multiplexing | Six independent channels support four modes per channel: A-select, B-select, A•B AND mask, or clear - eliminating need for discrete gate arrays in operand routing. |
| True/Complement Output Selection | COMP input toggles output polarity without external inverters - reduces component count and board area in signal conditioning stages. |
| Cascadable Operand Expansion | S0/S1/COMP and OPER=0 signals are fully routable between devices - enables 12-, 18-, or N×6 operand systems using daisy-chained control and flag lines. |
| Zero-Detection Flag (OPER = 0) | Dedicated open-collector–compatible output flags global zero condition across all selected operands - accelerates status polling in real-time diagnostics. |
| Bus-Compatible 3-State Outputs | All Y outputs and OPER=0 support simultaneous Hi-Z disable - allows direct connection to shared data/address buses without isolation logic or contention risk. |
Applications
| Avionics Data Routing | Military Test Equipment |
|---|---|
|
Use Scenario: Selecting between redundant sensor inputs (e.g., inertial measurement unit A/B channels) in flight control computers under DO-254 compliance. IC Role / Device Role / Timing Role: Hex multiplexer providing failover path selection with sub-30 ns propagation delay and deterministic zero-detection for health monitoring. Use Value: Enables real-time A/B channel arbitration without FPGA logic overhead; OPER=0 flag triggers immediate fault logging upon sensor dropout. |
Use Scenario: Configuring stimulus/response paths in automated test equipment (ATE) for legacy MIL-STD-1553B bus validation. IC Role / Device Role / Timing Role: Universal operand selector routing test vectors to DUT inputs while masking unused bits via AND mode. Use Value: Reduces fixture complexity by replacing multiple 74LS157s; 3-state outputs allow dynamic bus sharing across multiple test modules. |
| Secure Communication Modules | Radiation-Hardened Control Logic |
|
Use Scenario: Implementing key-switching logic in TEMPEST-compliant crypto modules where physical layer signal routing must avoid timing side channels. IC Role / Device Role / Timing Role: Deterministic, non-programmable multiplexer ensuring constant propagation delay regardless of selected operand or mode. Use Value: Prevents data-dependent timing leakage; ceramic JT package provides inherent EMI shielding and thermal stability for secure environments. |
Use Scenario: Building radiation-tolerant sequencers in satellite power management units requiring latch-up immunity and extended temperature operation. IC Role / Device Role / Timing Role: Core routing element in watchdog timer chains and reset distribution networks operating continuously at 125°C. Use Value: ALS process and ceramic packaging deliver proven TID tolerance >100 krad(Si); no derating required across full military temperature range. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar universal multiplexer applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SNJ54AS857JT | Faster propagation (18 ns max vs. 27 ns), higher ICC (up to 45 mA), same pinout and function - AS family offers improved speed at cost of increased power. | Better suited for high-clock-rate test instrumentation where <20 ns tpd is mandatory; less ideal for thermally constrained avionics bays. | Select SNJ54AS857JT only if system timing budget requires sub-20 ns path delay and thermal design accommodates +25% power draw. |
| 5962-8753301LA | Identical part number marking per TI's QML-38535 listing; same electrical specs, screening, and qualification - direct manufacturer-equivalent military specification part. | Required for DoD procurement requiring QML-38535 Class V or B certification; identical form, fit, and function with traceable lot documentation. | Choose 5962-8753301LA when formal QML certification, extended reliability testing, or government audit trail is contractually mandated. |
Compared with SNJ54ALS857JT, SNJ54AS857JT trades lower propagation delay for higher power consumption and thermal load, while 5962-8753301LA provides identical performance with certified QML-38535 pedigree - making the latter essential for defense prime integrations and the former optimal for speed-critical commercial test gear.
Availability
SNJ54ALS857JT is available at Aetrix Electronics and suitable for avionics data routing, military test equipment, secure communication modules, and radiation-hardened control logic requiring stable component supply across extended temperature and long-lifecycle programs.
Supply support for SNJ54ALS857JT 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 U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and high-reliability logic solutions for industrial, automotive, aerospace, and defense markets.
The SNJ54ALS857JT belongs to TI's military 54ALS logic family - designed specifically for high-stability, radiation-tolerant, and extended-temperature digital control in mission-critical systems where commercial-grade alternatives are unsuitable.
FAQ
What is the operating temperature range of the SNJ54ALS857JT?
The SNJ54ALS857JT is characterized for operation from –55°C to 125°C, meeting MIL-PRF-38535 requirements for military and aerospace applications. This full-range qualification ensures reliable functionality in extreme environmental conditions such as high-altitude flight, space vehicle thermal cycling, and ground-based radar systems exposed to desert or arctic climates. The SNJ54ALS857JT maintains specified timing and drive strength across this entire span without derating.
How does the OPER = 0 output function in the SNJ54ALS857JT?
The OPER = 0 output on the SNJ54ALS857JT is an active-high, open-collector–compatible flag that asserts logic high only when all currently selected A or B inputs (per channel) are simultaneously low. It is not a simple OR of individual channel zero flags - it reflects the collective state of the six selected operand bits. This feature enables rapid system-level zero-detection without software polling or additional logic gates, and is especially valuable in real-time fault-monitoring architectures within the SNJ54ALS857JT's target applications.
Can the SNJ54ALS857JT be used as a direct replacement for SN74ALS857 in existing designs?
No - the SNJ54ALS857JT is not a drop-in replacement for SN74ALS857 due to fundamental differences in temperature rating, output drive strength (12 mA vs. 24 mA), and qualification level. While pinout and logic function are identical, the SNJ54ALS857JT is rated for –55°C to 125°C and screened to military standards, whereas SN74ALS857 operates only from 0°C to 70°C and lacks QML certification. Substituting SNJ54ALS857JT into a commercial design may cause over-specification and unnecessary cost; substituting SN74ALS857 into a military design violates environmental and reliability requirements.
What are the valid logic states for the COMP, S0, and S1 inputs on the SNJ54ALS857JT?
The COMP, S0, and S1 inputs on the SNJ54ALS857JT accept standard TTL-compatible voltage levels: VIH ≥ 2.0 V (min), VIL ≤ 0.8 V (max). All three must be driven to valid high or low states - floating inputs are undefined and may cause erratic output behavior or increased ICC. Critically, placing all three (COMP, S0, S1) high simultaneously forces all Y outputs and OPER = 0 into high-impedance, which is the only guaranteed method to disable all outputs without affecting internal logic states. This behavior is explicitly defined in the SNJ54ALS857JT function table and verified across temperature.
Does the SNJ54ALS857JT support hot-swap or live-insertion on a powered backplane?
The SNJ54ALS857JT does not support hot-swap or live-insertion. Its absolute maximum ratings specify that VCC must be applied before any input signals, and inputs must remain within –0.5 V to VCC + 0.5 V at all times. Applying inputs prior to VCC or exceeding these limits risks latch-up or permanent damage. For backplane applications requiring hot-swap capability, external protection circuitry (e.g., series resistors, clamping diodes, and power sequencing controllers) must be implemented - the SNJ54ALS857JT itself contains no integrated hot-swap protection.
SNJ54ALS857JT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 54ALS
- Package/Case:
- 24-CDIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- Multiplexer
- Circuit:
- 6 x 2:1
- Independent Circuits:
- 1
- Current - Output High, Low:
- 1mA, 12mA
- Voltage Supply Source:
- Single Supply
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 24-CDIP
SNJ54ALS857JT FAQ
1.How can I place an order for SNJ54ALS857JT through Aetrix?
Please submit a Request for Quotation (RFQ) for SNJ54ALS857JT 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 SNJ54ALS857JT reliable?
The price and inventory of SNJ54ALS857JT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SNJ54ALS857JT is usually 5 days.
3.What payment methods are accepted for SNJ54ALS857JT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SNJ54ALS857JT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SNJ54ALS857JT?
SNJ54ALS857JT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SNJ54ALS857JT 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 SNJ54ALS857JT?
For technical support, including SNJ54ALS857JT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SNJ54ALS857JT requirements.
6.How does Aetrix verify that SNJ54ALS857JT is sourced from the original manufacturer or authorized distributors?
All SNJ54ALS857JT 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 SNJ54ALS857JT meets industry standards.
7.What is the process for return or replacement of SNJ54ALS857JT?
All SNJ54ALS857JT units undergo pre-shipment inspection (PSI). If there is an issue with SNJ54ALS857JT, 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 SNJ54ALS857JT part is unused and in its original packaging.
Return procedure for SNJ54ALS857JT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SNJ54ALS857JT 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…
