Nexperia USA Inc. CBT3257AD,112

Overview

CBT3257AD,112 from Nexperia is a quad 1-of-2 bus switch IC functioning as a high-speed analog/digital multiplexer-demultiplexer with active-Low output enable (OE) and shared select (S) control. It provides four independent SPDT switch paths, each with ≤7 Ω ON resistance at 5 V, <5.2 ns enable/disable timing, and TTL-compatible control inputs tolerant to 5.5 V - deployed in PCIe Gen3 signal routing, FPGA I/O expansion, and legacy parallel bus isolation.

For engineers reviewing the CBT3257AD,112 datasheet, CBT3257AD,112 pinout, CBT3257AD,112 application, or CBT3257AD,112 equivalent, key selection criteria include guaranteed 5 V operation, sub-5 ns switching latency, SO16 package compatibility with industrial temperature range (-40 °C to +85 °C), and overvoltage-tolerant OE/S inputs enabling direct interface with mixed-voltage logic domains.

Technical Context

The CBT3257AD implements four independent bidirectional analog switches controlled by a common select (S) line and global output enable (OE). Each switch connects one A-port terminal to either B1 or B2 based on S state when OE is LOW; all switches disable to high-impedance when OE is HIGH.

Its architecture uses NMOS pass transistors with integrated level-shifting for control inputs, enabling 5.5 V overvoltage tolerance on OE and S while operating from a 4.5–5.5 V VCC supply. Static characteristics include ±1 μA input leakage and 3 μA max ICC, supporting low-power system-level signal gating without loading source drivers.

Key Specifications

Pinout & Package

CBT3257AD,112 is supplied in SO16 (SOT109-1) package: plastic small outline, 16 leads, 3.9 mm body width, 1.27 mm lead pitch, JEDEC MS-012 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad SPDT bus switch applications.

Compared with SN74CBT3257PWR and 74LVC1G3157GW, CBT3257AD,112 uniquely balances quad-channel integration, 5 V operation, sub-7 Ω R_ON, and nanosecond switching - making it optimal for compact, high-speed industrial bus routing where timing predictability and voltage compatibility are non-negotiable.

Availability

CBT3257AD,112 is available at Aetrix Electronics and suitable for PCIe lane routing, FPGA I/O expansion, and legacy parallel bus isolation requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for CBT3257AD,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 focused on high-volume, high-reliability essential semiconductors - delivering robust logic, analog, and MOSFET solutions for industrial, computing, and consumer applications.

The CBT3257AD,112 belongs to Nexperia's advanced bus switch product line, engineered specifically for low-latency, low-distortion signal routing in 5 V digital systems where timing precision and voltage interoperability are critical.

FAQ

Is CBT3257AD,112 compatible with 3.3 V control logic?

No - CBT3257AD,112 requires VCC = 4.5–5.5 V and specifies VIH ≥ 2.0 V and VIL ≤ 0.8 V, but its control inputs are overvoltage-tolerant up to 5.5 V. Driving OE and S from 3.3 V logic is acceptable only if VCC is 5 V and the 3.3 V driver meets the 2.0 V VIH minimum; however, full 5 V logic is recommended for guaranteed noise margin and timing performance.

Can unused A or B terminals be left floating?

No - all A and B terminals must be terminated to a defined voltage (VCC or GND) when not actively driven, per Nexperia's recommended operating conditions. Floating terminals increase susceptibility to ESD-induced latch-up and may cause unpredictable switching behavior due to capacitive coupling or noise pickup on high-impedance nodes.

What is the maximum continuous current per switch channel?

The absolute maximum continuous switch current is 128 mA per channel, as specified in Table 4 (Limiting Values). However, for reliable operation within recommended conditions, the static characteristics table confirms R_ON is characterized at 30 mA (max 7 Ω) and 64 mA (max 7 Ω), indicating 30–64 mA is the practical design limit for maintaining low distortion and thermal stability.

Does CBT3257AD,112 support hot-swap or live-insertion?

Yes - its overvoltage-tolerant OE and S inputs (rated to 5.5 V independent of VCC), combined with latch-up immunity exceeding 100 mA and ESD protection >2000 V HBM, enable safe operation during hot-swap events. However, VCC must be stable before asserting OE LOW; sequencing control logic to assert OE only after VCC reaches 4.5 V ensures robust startup behavior.