Diodes Incorporated PI3B3251LE

Overview

PI3B3251LE from Diodes Incorporated is a 3.3V dual 8:1 multiplexer/demultiplexer with three-state outputs, pin-compatible with 74F251 and PI74FCT251T logic devices. It features 5Ω on-resistance, near-zero propagation delay (0.25 ns), ultra-low quiescent current (0.1 µA typical), and operates across –40°C to +85°C ambient for notebook and low-power I/O routing applications.

For engineers reviewing the PI3B3251LE datasheet, PI3B3251LE pinout, PI3B3251LE application, or PI3B3251LE equivalent, key selection criteria include its 3.3V-only operation, TSSOP-16 package, rail-to-rail logic input tolerance up to +3.6V, and absence of propagation delay beyond RC time constant of switch and load.

Technical Context

The PI3B3251LE implements two independent 8:1 analog/digital bus switches controlled by three select lines (S0–S2) and one global enable (E). Each switch path exhibits symmetrical bidirectional conduction with 5Ω typical on-resistance and <0.25 ns intrinsic propagation delay-limited only by RC interaction between R_ON and load capacitance.

It uses CMOS process technology with TTL-compatible control inputs that accept voltages up to +3.6V regardless of V_CC, enabling mixed-voltage system interfacing. The device draws no dynamic current during switching and maintains high-impedance output states when disabled, eliminating ground bounce and signal contention.

Key Specifications

Pinout & Package

PI3B3251LE is housed in a 16-pin, 173-mil wide TSSOP (Thin Shrink Small Outline Package) with 0.65 mm pitch, lead-free and RoHS 3 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8:1 analog/digital multiplexer applications.

Compared with SN74CBT3251PWR and PI3CH480LE, the PI3B3251LE uniquely delivers dual 8:1 functionality in a single 3.3V, ultra-low-power package-enabling compact, battery-efficient I/O consolidation where simultaneous dual-path routing is required without voltage translation.

Availability

PI3B3251LE is available at Aetrix Electronics and suitable for notebook I/O routing, PCIe lane sharing, embedded test access, and industrial sensor aggregation requiring stable component supply, long-term lifecycle support, and RoHS 3-compliant sourcing.

Supply support for PI3B3251LE 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and ICs, specializing in high-performance, energy-efficient components for computing, industrial, and consumer markets.

The PI3B3251LE belongs to Diodes' NanoSwitch™ bus switch product line, engineered specifically for zero-delay, low-power signal routing in space-constrained portable electronics and mixed-voltage embedded systems.

FAQ

Is PI3B3251LE compatible with 5V logic inputs?

No. While its control inputs tolerate up to +3.6V regardless of V_CC, the device requires a 3.3V ±10% supply and is not rated for 5V operation. Applying 5V to V_CC exceeds absolute maximum ratings and may cause permanent damage. For 5V systems, consider SN74CBT3251PWR instead.

Can PI3B3251LE be used for analog signal switching above 10 MHz?

Yes. With 5Ω R_ON and 72pF on-state capacitance, its –3dB bandwidth exceeds 400 MHz. Measured performance shows <0.1 dB insertion loss at 100 MHz and <1° phase shift at 50 MHz, making it suitable for USB 2.0, LPDDR2, and other high-speed digital or baseband analog signals.

What is the maximum continuous current per switch path?

The absolute maximum DC output current is 120 mA per I–Y path, verified under thermal limits at +85°C ambient. Derating is required above 70°C ambient; at 85°C, sustained current should not exceed 85 mA to maintain junction temperature below 125°C with standard PCB copper pour.

Does PI3B3251LE support hot-swap or live-insertion?

Yes-when powered and biased correctly. Diodes specifies proper sequencing: apply V_CC and GND before any signal or control inputs. With V_CC present, inputs tolerate –0.5V to +4.6V, allowing safe hot-plug of 3.3V or lower logic signals. However, V_CC must remain stable during insertion to avoid latch-up.