Diodes Incorporated PI5C3861QE

Overview

PI5C3861QE from Pericom Semiconductor is a 10-bit, 2-port bus switch IC with 5 Ω on-resistance, active-low Bus Enable (BE) control, and 24-pin QSOP package. It provides bidirectional signal routing between Bus A (A0–A9) and Bus B (B0–B9), supports 5 V operation, delivers near-zero propagation delay (0.25 ns), and draws only 0.2 μA quiescent current - used in notebook I/O expansion and low-power peripheral switching.

For engineers reviewing the PI5C3861QE datasheet, PI5C3861QE pinout, PI5C3861QE application, or PI5C3861QE equivalent, key selection criteria include on-resistance matching, BE-controlled high-impedance isolation, 50 pF load-compatible timing, and Pb-free QSOP packaging compliance for portable embedded systems.

Technical Context

The PI5C3861QE implements ten independent analog/digital MOSFET transmission gates controlled by a single active-low BE input. Each switch exhibits matched on-resistance (5 Ω typ. at V_CC = 4.5 V, I_ON = 48 mA) and negligible propagation delay - limited only by RC time constant of R_ON and load capacitance (e.g., ~0.25 ns for 50 pF).

It operates over –40°C to +85°C ambient, accepts 4.5–5.5 V supply, guarantees TTL-compatible input thresholds (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V), and maintains high-impedance state (I_OZ ≤ ±1 μA) when disabled - eliminating ground bounce and signal contention in shared-bus architectures.

Key Specifications

Pinout & Package

PI5C3861QE is housed in a 24-pin, 150-mil wide plastic QSOP (Quad Small Outline Package) with 0.635 mm pitch, Pb-free and RoHS-compliant (Green) construction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit bus switch applications.

Compared with SN74CBT3384APW and 74LVC1G3157GW, PI5C3861QE offers the lowest on-resistance (5 Ω) in a single 24-pin QSOP, enabling tighter voltage margins and lower system-level jitter - critical for notebook and industrial backplane designs demanding signal fidelity and compact layout.

Availability

PI5C3861QE is available at Aetrix Electronics and suitable for notebook I/O expansion, industrial PLC backplane multiplexing, and embedded display interface switching requiring stable component supply, long-term lifecycle support, and Pb-free manufacturing compliance.

Supply support for PI5C3861QE 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-performance interface, timing, and signal integrity solutions, acquired by Diodes Incorporated in 2016; its legacy bus switch portfolio remains widely deployed in computing and industrial systems.

The PI5C3861QE belongs to Pericom's low-voltage CMOS bus switch product line, engineered specifically for zero-delay, low-power signal routing in portable and space-constrained embedded platforms.

FAQ

What is the maximum capacitive load the PI5C3861QE can drive while maintaining specified timing?

The PI5C3861QE is characterized for CL = 50 pF and RL = 500 Ω, delivering 0.25 ns propagation delay. Its 5 Ω R_ON forms an RC network with load capacitance; for loads up to 100 pF, delay increases linearly but remains under 0.5 ns. Signal integrity beyond 100 pF depends on source drive strength and trace impedance matching - not guaranteed by datasheet specs.

Can PI5C3861QE operate reliably at 3.3 V supply?

No. The PI5C3861QE is specified only for 4.5–5.5 V operation. At 3.3 V, R_ON rises significantly (>15 Ω), VIH/VIL thresholds become non-TTL compliant, and BE control may fail to fully disable switches. For 3.3 V systems, consider Diodes' PI3CHD3245 or ON Semiconductor's NLAS3245 as functional alternatives.

Is the NC pin on PI5C3861QE required to be grounded or left floating?

The NC pin is internally unconnected and must be left floating per datasheet guidance. Grounding it may introduce unintended parasitic coupling or violate package thermal design rules. Layout best practice recommends keeping NC pins un-routed and clear of copper pour to avoid EMI coupling or solder wicking during reflow.

Does PI5C3861QE support hot-swap or live-insertion applications?

Yes - its high-impedance disable state (I_OZ ≤ ±1 μA), rail-to-rail input tolerance (–0.5 V to +7.0 V), and absence of power-on reset or sequencing requirements make it suitable for hot-swap I/O domains. However, external series resistors and TVS diodes are still recommended on A/B lines to limit inrush current and ESD stress during insertion.