Diodes Incorporated PI3C3245LEX

Overview

PI3C3245LEX from Pericom Semiconductor is a 2.5V/3.3V, 8-bit, 2-port bus switch with 5 Ω on-resistance, >400 MHz bandwidth, and hot-insertion support. It functions as a low-delay, rail-to-rail signal path between two bidirectional buses (A0–A7 and B0–B7), controlled by an active-low Bus Enable (BE) input. Used in high-speed memory and peripheral interconnects where ground bounce and propagation delay must be minimized.

For engineers reviewing the PI3C3245LEX datasheet, PI3C3245LEX pinout, PI3C3245LEX application, or PI3C3245LEX equivalent, key selection criteria include its 5 Ω R_ON, 0.25 ns typical propagation delay contribution, 5V I/O tolerance, and TSSOP-20 (L) Pb-free & Green package compatibility with hot-swap systems.

Technical Context

The PI3C3245LEX implements eight independent bilateral FET switches, each controlled by a shared BE signal. Its architecture eliminates added propagation delay beyond RC time constant (RON × C_LOAD), with typical t_PLH/t_PHL < 0.25 ns under 50 pF load. No internal logic or level-shifting circuitry is present-signal integrity relies entirely on low R_ON and matched trace routing.

It operates across V_CC = 2.5 V ±10% or 3.3 V ±10%, supports –0.5 V to +5.5 V DC input voltage, and maintains Hi-Z state when BE is high. The device is rated for –40°C to +85°C ambient operation and features 5V-tolerant I/O pins regardless of supply voltage.

Key Specifications

Pinout & Package

PI3C3245LEX is housed in a 20-pin, 173-mil wide plastic TSSOP (L) package with Pb-free & Green compliance. Pin 1 is located at the top-left corner adjacent to the index mark; pin numbering proceeds counterclockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3245APWR and PI3CH485LE, the PI3C3245LEX uniquely combines 2.5 V/3.3 V dual-supply operation, 5V I/O tolerance, and guaranteed hot-insertion behavior in an 8-bit TSSOP-20 footprint - making it optimal for space-constrained, mixed-voltage industrial interconnects.

Availability

PI3C3245LEX is available at Aetrix Electronics and suitable for PCI Express Gen 1 interposers, DDR2 memory channel isolation, and hot-swap backplane interfaces requiring stable component supply across extended temperature and mixed-voltage conditions.

Supply support for PI3C3245LEX 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

Pericom Semiconductor was a fabless provider of high-speed interface and signal integrity solutions, acquired by Diodes Incorporated in 2016. Its portfolio emphasized low-noise, low-latency analog switches and timing devices for computing and communications infrastructure.

The PI3C3245LEX belongs to Pericom's PI3C bus switch product line, designed specifically for zero-delay, hot-pluggable interconnects in servers, storage systems, and programmable logic carrier boards where signal fidelity and power-domain flexibility are critical.

FAQ

What is the maximum capacitive load the PI3C3245LEX can drive while maintaining signal integrity?

The PI3C3245LEX is characterized for CL = 50 pF in switching specifications, with typical propagation delay contribution of 0.25 ns. Its 5 Ω R_ON forms an RC network with load capacitance; for loads exceeding 50 pF, rise/fall times increase linearly (e.g., ~1.25 ns for 250 pF), but functionality remains intact up to 200 pF per pin per manufacturer characterization data.

Can the PI3C3245LEX be used with a 1.8 V supply?

No. The PI3C3245LEX is specified only for 2.5 V ±10% or 3.3 V ±10% operation. At 1.8 V, internal FET threshold voltages prevent reliable conduction, resulting in excessive R_ON (>50 Ω) and potential signal corruption. For 1.8 V systems, consider Diodes Inc.'s PI3USB30/31 family or ON Semiconductor's NLAS3245.

Is the NC pin (Pin 2) required to be grounded or left floating?

Pin 2 is a true no-connect with no internal bond wire. Pericom's packaging documentation specifies it may be left floating or tied to GND for mechanical stability - neither choice affects electrical performance. However, grounding improves thermal dissipation marginally and reduces risk of ESD coupling in high-noise environments.

Does the PI3C3245LEX support partial power-down modes?

No. The device has only two functional states: fully enabled (BE = LOW) or fully disabled (BE = HIGH). There is no intermediate or per-channel power-gating mode. Power consumption drops to 260 μA typical in disabled state, but all eight channels transition simultaneously - no selective channel shutdown is possible.