Nexperia USA Inc. CBT3251DB,112

Overview

CBT3251DB,112 from Nexperia is a 1-of-8 FET bus switch configured as a single-pole, 8-throw multiplexer/demultiplexer with active-Low output enable (OE), three binary select inputs (S0–S2), 5 Ω typical ON resistance at 5 V, ±1 μA input leakage, and operation from –40 °C to +85 °C. It routes one A port bidirectionally to any of eight B ports in high-speed digital signal path switching applications such as address/data bus routing in microcontroller peripherals.

For engineers reviewing the CBT3251DB,112 datasheet, CBT3251DB,112 pinout, CBT3251DB,112 application, or CBT3251DB,112 equivalent, key selection criteria include ON-resistance consistency across channels, TTL-compatible control voltage thresholds, IOFF partial power-down capability, and SO16 package thermal and layout compatibility with legacy 3.9 mm-body small-outline footprints.

Technical Context

The CBT3251DB,112 implements an analog-switch-based 1:8 bidirectional signal path using integrated FETs with no internal logic latching-switch state follows real-time S0–S2 and OE levels. Its IOFF circuitry blocks current flow when VCC = 0 V, enabling live insertion and hot-swap support in backplane or modular systems.

Control inputs tolerate up to 5.5 V regardless of VCC level, allowing direct interfacing with 3.3 V or 5 V logic families without level shifters. Propagation delay is limited to 0.25 ns (A↔Bn) and enable/disable times remain under 6.4 ns, supporting >300 MHz data rates in low-voltage differential signaling paths.

Key Specifications

Pinout & Package

CBT3251DB,112 is packaged in SO16 (SOT109-1), a plastic small outline package with 16 leads and 3.9 mm body width. Pin 1 is marked by a notch or bevel; the package is lead (Pb)-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 1-of-8 FET multiplexer applications.

Compared with SN74CBT3251PWR and 74LVC1G3157GW,125, the CBT3251DB,112 delivers superior industrial robustness via higher latch-up rating and ESD tolerance, while its monolithic 1-of-8 architecture reduces PCB area and interconnect complexity versus multi-device solutions.

Availability

CBT3251DB,112 is available at Aetrix Electronics and suitable for industrial control systems, test instrumentation signal routing, and embedded peripheral expansion requiring stable component supply, long-term lifecycle assurance, and SO16 footprint compatibility.

Supply support for CBT3251DB,112 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

Nexperia is a global semiconductor expert specializing in high-performance, reliable discrete, logic, and MOSFET devices for automotive, industrial, and consumer markets.

The CBT3251 belongs to Nexperia's advanced bus switch family, engineered specifically for low-latency, low-distortion signal routing in high-speed digital systems where analog switch fidelity and TTL interoperability are critical.

FAQ

Can CBT3251DB,112 operate with a 3.3 V supply?

No. The CBT3251DB,112 is specified only for 4.5 V to 5.5 V operation per Table 5. At 3.3 V, RON increases beyond 15 Ω and VIH/VIL thresholds become noncompliant with TTL logic levels, risking unreliable switching. Use 74LVC1G3157 or similar 1.65–5.5 V switches instead.

Is the n.c. pin (pin 6) required to be grounded or left floating?

Pin 6 is a true no-connect-internally unconnected and electrically isolated. It must remain unpopulated on the PCB and not tied to GND, VCC, or any other net. Leaving it floating poses no risk; grounding it may introduce parasitic capacitance or contamination paths.

Does CBT3251DB,112 support hot-swap insertion?

Yes. Its IOFF circuitry actively blocks current flow when VCC = 0 V, preventing backfeeding into powered subsystems. This enables safe insertion into live backplanes provided OE is held HIGH until VCC stabilizes and control signals are valid.

What is the maximum capacitive load the CBT3251DB,112 can drive without signal degradation?

Per Table 9 test conditions, the device is characterized with 50 pF load capacitance and maintains tPLH ≤ 7.0 ns. Driving >100 pF increases propagation delay nonlinearly and may cause ringing; for >50 pF loads, add series termination or reduce trace length to maintain signal integrity.