SN74CBTLV3257PWR - 4-Bit 2:1 FET Mux 5Ω | TI
MPN: SN74CBTLV3257PWR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.44 | $0.44 |
| 10 | $0.4 | $4.00 |
| 100 | $0.34 | $34.00 |
| 500 | $0.3 | $150.00 |
| 1,000 | $0.27 | $270.00 |
SN74CBTLV3257PWR Overview
A multiplexer/demultiplexer is a signal-routing switch that directs one of several inputs to a common output, or vice versa. Within the logic and signal-switching hierarchy, the SN74CBTLV3257 belongs to the CBTLV family of bus (FET) switches, which sit between simple logic gates and full analog multiplexer ICs, optimized for low capacitance and low ON-resistance to preserve signal integrity.
Key features include a typical ON-state resistance of 5 ohms, an operating supply range of 2.3 V to 3.6 V, and a partial-power-down mode that places I/Os in high impedance when VCC is 0 V. I/Os are over-voltage tolerant to 5 V, allowing mixed-voltage signaling. The 16-pin TSSOP package measures 5 mm x 6.4 mm with a 0.65-mm pitch for space-constrained PCBs.
The device uses a pass-gate (FET) architecture that is fully bidirectional, with typical propagation delay of 0.25 ns and low channel-to-channel crosstalk. An output-enable (OE) pin drives all outputs to high impedance when low, supporting bus isolation, while the select (S) pin routes each channel between its A and B ports.
Typical applications include high-speed signal routing in networking equipment, data acquisition systems, test instrumentation, and mixed-voltage bus switching in computing platforms. Low ON-resistance suits clock and data distribution where edge fidelity matters.
Design tip: tie OE to VCC through a pull-up resistor to guarantee high-impedance OFF-state during power-up and power-down, per the TI/NXP datasheet, preventing bus contention during multi-rail power sequencing. Pricing as of 2026-08-30 starts near $0.27 per unit at volume.
Drop-in alternatives for SN74CBTLV3257PWR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with SN74CBTLV3257PWR (same form factor and footprint) — differing in Function, Operating Temperature, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SN74CBTLV3257PW
✅ Drop-In📋 Reference alternative (not in catalog)
SN74CBTLV3257PWREP
✅ Drop-In📋 Reference alternative (not in catalog)
74CBTLV3257PW,118
✅ Drop-In📋 Reference alternative (not in catalog)
SN74CBT3257PWR
⚡ Same Package📋 Reference alternative (not in catalog)
74CBTLV3257BQ,115
⚡ Same Package ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
SN74CBTLV3257PWR Maximum Ratings & Electrical Characteristics
| Function | 4-Bit 1-of-2 FET Multiplexer/Demultiplexer |
| Channels | 4 x 2:1 (SPDT) |
| ON-State Resistance | 5 ohm (typical) |
| Supply Voltage Range | 2.3 V to 3.6 V |
| I/O Voltage Tolerance | 5 V (over-voltage tolerant) |
| Propagation Delay | 0.25 ns (typical) |
| Partial Power-Down Mode | Yes (I/Os high-impedance at VCC = 0 V) |
| Output Enable | Yes (OE, active-high) |
| Select Input | Yes (S pin) |
| Architecture | Pass-gate FET, bidirectional |
| Operating Temperature | -40C to +85C |
| Package | 16-TSSOP (PW), 5 mm x 6.4 mm |
| Package Pitch | 0.65 mm |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lifecycle Status | Active |
SN74CBTLV3257PWR Pin Configuration
| Pin 1 | 1B1 — Channel 1 B-port, select side 1 |
| Pin 2 | 1A — Channel 1 A-port (common) |
| Pin 3 | 1B2 — Channel 1 B-port, select side 2 |
| Pin 4 | 2B1 — Channel 2 B-port, select side 1 |
| Pin 5 | 2A — Channel 2 A-port (common) |
| Pin 6 | 2B2 — Channel 2 B-port, select side 2 |
| Pin 7 | S — Select input: routes A to B1 (L) or B2 (H) |
| Pin 8 | GND — Ground |
| Pin 9 | 3B1 — Channel 3 B-port, select side 1 |
| Pin 10 | 3A — Channel 3 A-port (common) |
| Pin 11 | 3B2 — Channel 3 B-port, select side 2 |
| Pin 12 | 4B1 — Channel 4 B-port, select side 1 |
| Pin 13 | 4A — Channel 4 A-port (common) |
| Pin 14 | 4B2 — Channel 4 B-port, select side 2 |
| Pin 15 | OE — Output enable: high = switch active, low = high impedance |
| Pin 16 | VCC — Supply, 2.3 V to 3.6 V |
Typical Applications
SN74CBTLV3257PWR is suitable for 6 applications: Networking Equipment Signal Routing, Data Acquisition Systems, Test and Measurement Instrumentation, Mixed-Voltage Bus Switching, Industrial Automation Control, Automotive Telematics Modules.
Networking Equipment Signal Routing
In switches, routers, and line cards, the SN74CBTLV3257PWR routes high-speed clock and data lines between redundant paths. Its 5 ohm ON-resistance and 0.25 ns typical propagation delay preserve edge rates on digital lines, while the 5 V tolerant I/Os allow it to sit on mixed 3.3 V/5 V backplanes. The partial-power-down mode prevents back-powering through the switch when a line card is unpowered. Place the device near the connector with short controlled-impedance traces; low channel capacitance of the FET architecture minimizes insertion-loss degradation at high frequencies.
Recommended
Data Acquisition Systems
In DAQ front ends, the SN74CBTLV3257PWR selects between two sensor or amplifier outputs feeding a shared ADC driver stage. The 5 ohm ON-resistance contributes negligible series error compared with typical source impedances, and the bidirectional FET switch passes analog levels within the supply rail without added distortion. The S select pin allows channel switching under MCU control, and OE isolates the ADC input during reconfiguration to prevent transients. Verify signal swing stays within the 2.3 V to 3.6 V supply; signals beyond the rails are clamped.
Recommended
Test and Measurement Instrumentation
Bench instruments and automated test equipment use the SN74CBTLV3257PWR to switch calibration paths and route signals between measurement channels. The 0.25 ns propagation delay and symmetric bidirectional switching keep timing references consistent regardless of path direction, and 5 V tolerance protects the switch when probes touch 5 V logic domains. The -40C to +85C rating covers typical lab environments. For best repeatability, keep the ON path as short as possible and account for the roughly 5 ohm series resistance when measuring low-impedance nodes.
Recommended
Mixed-Voltage Bus Switching
In computing platforms combining 3.3 V and 5 V legacy buses, the SN74CBTLV3257PWR isolates or connects bus segments thanks to 5 V tolerant I/Os and the partial-power-down feature that tri-states all I/Os at VCC = 0 V. This prevents contention and back-driving during power sequencing. The OE pin, pulled up to VCC per datasheet guidance, guarantees high impedance during brownout. Designers should sequence VCC before bus activity begins and confirm that downstream 5 V drivers do not exceed the switch current limits.
Recommended
Industrial Automation Control
PLCs and factory automation modules use the SN74CBTLV3257PWR to multiplex sensor inputs and select redundant actuator feedback lines. The 2.3 V to 3.6 V operation suits 3.3 V controller logic, and the -40C to +85C industrial temperature range covers cabinet environments. Its 5 ohm switch connection adds minimal error to signal paths, while OE enables safe isolation during maintenance. Protect inputs against inductive transients with external clamping, since the switch tolerates only signals within about 4 V regardless of supply.
Recommended
Automotive Telematics Modules
Telematics and body-control submodules route CAN, LIN, or sensor signals through the SN74CBTLV3257PWR where a 3.3 V switch domain exists. TI's enhanced-product variant with -55C to +125C capability is recommended for under-hood conditions; the standard part suits in-cabin modules within -40C to +85C. The partial-power-down mode prevents parasitic paths when the module sleeps, supporting low quiescent-power budgets. Note the standard part is not AEC-Q100 qualified; specify the EP version or an automotive-grade switch for certified designs.
Recommended
Recommended Products Summary
Engineering reference data for SN74CBTLV3257PWR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN74CBTLV3257PW | SN74CBTLV3257PWREP | 74CBTLV3257PW,118 | SN74CBT3257PWR | 74CBTLV3257BQ,115 |
|---|---|---|---|---|---|---|
| Package | 16-TSSOP (PW), 5 mm x 6.4 mm | 16-TSSOP (PW) - same | 16-TSSOP (PW) - same | 16-TSSOP (PW) - same | 16-TSSOP (PW) - same | DHVQFN-16 - different footprint |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Nexperia | Texas Instruments | Nexperia |
| Supply Voltage | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 2.3 V to 3.6 V | 4 V to 5.5 V | 2.3 V to 3.6 V |
| ON-Resistance (typ) | 5 ohm | 5 ohm | 5 ohm | 5 ohm class | 5 ohm class (5 V operation) | 5 ohm class |
| Channels | 4 x 2:1 (SPDT) | 4 x 2:1 | 4 x 2:1 | 4 x 2:1 | 4 x 2:1 | 4 x 2:1 |
| Operating Temperature | -40C to +85C | -40C to +85C | -55C to +125C | -40C to +85C | -40C to +85C | -40C to +85C |
| Qualification | Standard commercial | Standard | EP enhanced qualification pedigree | Standard | Standard | Standard |
Key Differentiators
- 5 V tolerant I/Os on a 3.3 V switch (vs SN74CBT3257PWR)
- Extended-temperature drop-in available in same footprint (vs SN74CBTLV3257PWREP)
- Dual-sourcing with pin-compatible second source (vs 74CBTLV3257PW,118)
Design Notes
Per the TI/NXP datasheets, tie OE to VCC through a pull-up resistor so the switch stays in high-impedance OFF-state during power-up and power-down. Size the resistor based on the driving circuit current-sinking capability. Without this, during multi-rail sequencing the FET switch can power up in an undefined state and back-drive a live bus from an unpowered rail, potentially damaging drivers on either side.
The FET pass-gate has 0.25 ns typical propagation delay, but the ~5 ohm ON-resistance and channel capacitance form an RC low-pass with trace and load capacitance. For high-speed clock routing, keep switched traces short, use 50-ohm controlled impedance, and place the switch close to the source. Compute the RC corner: e.g., 5 ohm with 15 pF load gives roughly 2.1 GHz bandwidth, ample for most logic but degraded by long stubs.
Signals passed through the CBTLV3257 must remain within GND - 2 V to VCC + 2 V bounds per the datasheet; the 5 V tolerance applies to I/O ratings but signals beyond the rails are clamped by the FET body junctions. Ensure VCC is present before applying 5 V signals on a 3.3 V supply, or rely on partial-power-down isolation only when VCC = 0 V and no active drivers are on the bus.
Compliance Information
RoHS compliant per TI product page and LCSC listing. AEC-Q100 qualification applies to the enhanced-product SN74CBTLV3257-EP, not the standard part.
