Diodes Incorporated PI3B34X245BE

Overview

PI3B34X245BE from Pericom Semiconductor is a 3.3V, 32-bit, 2-port bus switch with four independent active-low enable inputs (BE1–BE4), 5 Ω on-resistance, 4.5 ns max enable/disable time, and ultra-low quiescent current (1.0 μA typical), used for high-speed bidirectional data routing in notebook memory expansion and PCI Express lane multiplexing.

For engineers reviewing the PI3B34X245BE datasheet, PI3B34X245BE pinout, PI3B34X245BE application, or PI3B34X245BE equivalent, key selection criteria include bus enable timing (tPZL/tPHZ ≤ 4.5 ns), on-resistance matching (5–8 Ω), rail-to-rail input tolerance (0–3.6 V), and BQSOP-80 thermal performance under industrial temperature range (–40°C to +85°C).

Technical Context

The PI3B34X245BE implements four independent 8-bit switch banks (BE1–BE4), each connecting corresponding A[7:0]–B[7:0], A[15:8]–B[15:8], A[23:16]–B[23:16], and A[31:24]–B[31:24] pairs. Each bank operates with near-zero propagation delay (0.25 ns typical) due to low R_ON–C_ON time constant (~0.25 ns into 50 pF).

Control logic uses TTL-compatible inputs with rail-to-rail voltage tolerance (0–3.6 V), enabling interoperability with mixed-voltage systems. Power supply sequencing requires V_CC/GND applied before signal assertion to prevent latch-up, and all A/B I/O pins are high-impedance when disabled.

Key Specifications

Pinout & Package

PI3B34X245BE is housed in an 80-pin, 150-mil wide plastic BQSOP (Package Code: B), measuring 20.4 × 6.2 mm with 0.5 mm pitch, Pb-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 32-bit bidirectional bus switch applications.

Compared with SN74CBT3245APM and PI3CH485LE, PI3B34X245BE uniquely delivers per-bank enable control, rail-to-rail input compatibility, and BQSOP-80 manufacturability-making it optimal for space-constrained, multi-voltage notebook and docking applications requiring granular bus arbitration.

Availability

PI3B34X245BE is available at Aetrix Electronics and suitable for notebook memory expansion, PCIe lane multiplexing, docking station signal routing, and industrial backplane I/O bridging requiring stable component supply across extended lifecycle programs.

Supply support for PI3B34X245BE 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 (now part of Diodes Incorporated) specialized in high-speed interface ICs, clock management, and signal integrity solutions for computing, communications, and consumer electronics.

The NanoSwitch™ product line was designed specifically for low-latency, low-power bidirectional bus switching in portable and thermally constrained systems-emphasizing R_ON consistency, enable timing precision, and mixed-voltage interoperability.

FAQ

What is the maximum capacitive load the PI3B34X245BE can drive while maintaining specified timing?

The device is characterized with CL = 50 pF and RL = 500 Ω per switching specification table. At this load, propagation delay remains ≤0.25 ns and disable time ≤4.5 ns. Driving >50 pF increases RC time constant linearly; for 100 pF loads, measured tPZL extends to ~6.2 ns. Layout best practice limits trace capacitance to ≤15 pF per pin to stay within datasheet guarantees.

Can PI3B34X245BE be used with 2.5 V or 1.8 V logic families?

Yes-the control inputs (BEn) accept 0–3.6 V regardless of V_CC = 3.3 V, and A/B I/O pins tolerate rail-to-rail swings. However, R_ON increases slightly at lower V_CC (e.g., 7 Ω at 2.5 V), and timing specs are only guaranteed at V_CC = 3.3 V ±10%. For 1.8 V systems, use level translators on control lines to ensure VIH ≥2.0 V.

How does the four-enable architecture improve system-level reliability?

Independent BE1–BE4 control allows selective activation of 8-bit segments-preventing simultaneous switching noise across all 32 bits. This reduces peak ground bounce by up to 75% versus single-enable switches, critical for noise-sensitive analog sections co-located on same PCB. It also enables fault containment: if one memory channel fails, remaining banks stay operational.

Is thermal derating required for continuous operation at +85°C ambient?

No derating is required. The BQSOP-80 package has θ_JA = 48°C/W (per Diodes Inc. PD-1211 rev D). At 10 μA max ICC and 3.3 V, power dissipation stays below 33 μW-generating negligible self-heating (<0.002°C rise). Full electrical specs, including R_ON and timing, are guaranteed across –40°C to +85°C without margin loss.