Renesas QS3VH384QG8

Overview

QS3VH384QG8 from Renesas Electronics (formerly IDT) is a 10-bit, high-bandwidth bus switch with N-channel FET architecture, rail-to-rail 0–5 V analog/digital signal switching, 4 Ω typical ON resistance, and 500 MHz bandwidth. It operates from 2.3 V to 3.6 V VCC and supports hot-swapping in Ethernet LAN switches and ATM systems.

For engineers reviewing the QS3VH384QG8 datasheet, QS3VH384QG8 pinout, QS3VH384QG8 application, or QS3VH384QG8 equivalent, key selection criteria include bidirectional zero-delay data flow, 5 V tolerance in both ON/OFF states, industrial temperature range (–40°C to +85°C), and independent dual-bank enable control (1OE/2OE) for flexible bus partitioning.

Technical Context

The QS3VH384QG8 implements two independent 5-bit switch banks (A0–A4/B0–B4 and A5–A9/B5–B9), each controlled by dedicated LVTTL-compatible OE inputs. Its N-channel FET design eliminates parasitic diodes to VCC, enabling true isolation under power-off conditions and no DC path to VCC or GND.

It delivers rail-to-rail analog switching (0–5 V), flat RON vs. VIN characteristics, excellent channel-to-channel RON matching, and low I/O capacitance (4 pF typical in OFF state). Propagation delay is under 250 ps, dominated only by RC time constant of RON and load capacitance-not internal logic.

Key Specifications

Pinout & Package

QS3VH384QG8 is packaged in 24-pin QSOP (Green, lead-free), with 0.635 mm pitch and 8.65 mm × 3.9 mm body size.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3384CPWR and PI3CHD384LEX, the QS3VH384QG8 uniquely combines 5 V tolerance in both ON/OFF states, undershoot clamps on all pins, and industrial temperature qualification-making it the only option qualified for zero-downtime hot-swap systems operating across wide ambient ranges.

Availability

QS3VH384QG8 is available at Aetrix Electronics and suitable for Fast Ethernet LAN switches, ATM 25/155 Mbps infrastructure, hot-swappable I/O cards, and low-distortion analog multiplexing requiring stable component supply and long-term industrial-grade availability.

Supply support for QS3VH384QG8 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

Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and connectivity solutions for automotive, industrial, infrastructure, and IoT applications.

The QS3VH384QG8 belongs to Renesas' QuickSwitch® bus switch family, designed specifically for high-bandwidth, low-latency signal routing in hot-pluggable and mixed-voltage communications systems.

FAQ

What is the maximum signal voltage the QS3VH384QG8 can switch while powered from 3.3 V?

The QS3VH384QG8 supports rail-to-rail switching from 0 V to 5 V on all A/B I/O pins, regardless of VCC being 2.5 V or 3.3 V. This 5 V tolerance applies in both ON and OFF states, enabling safe interfacing with 5 V peripherals without level shifters or clamping circuits. The device achieves this through its N-channel FET structure with no parasitic diode to VCC, and built-in undershoot clamp diodes protect against transients down to –3 V.

Does the QS3VH384QG8 require external pull-up or pull-down resistors on its OE inputs?

No, the QS3VH384QG8 does not require external biasing on 1OE or 2OE inputs. Its LVTTL-compatible control inputs have guaranteed VIH (2.0 V min at VCC = 2.7–3.6 V) and VIL (0.8 V max), and input leakage is ±1 μA over temperature-low enough to be driven directly by standard FPGA or ASIC GPIOs. Internal design ensures clean, noise-immune enable/disable transitions without external resistors.

How does the QS3VH384QG8 achieve near-zero propagation delay?

The QS3VH384QG8 achieves under 250 ps propagation delay by eliminating active logic in the signal path: it uses pure N-channel FET switches with no series gate driver or buffering. Delay arises solely from the RC time constant of RON (~4 Ω) and load capacitance (e.g., 50 pF → ~0.2 ns). Since this is far smaller than typical driver rise/fall times, the QS3VH384QG8 adds negligible latency-making it ideal for timing-critical interconnects where deterministic delay matters.

Can the QS3VH384QG8 be used to replace mechanical relays in analog signal paths?

Yes, the QS3VH384QG8 is explicitly positioned as a mechanical relay replacement in low-distortion analog applications. Its 4 Ω RON, flat RON vs. VIN curve, 4 pF OFF capacitance, and rail-to-rail 0–5 V operation deliver THD <–80 dBc at 10 kHz-meeting precision instrumentation requirements. Unlike relays, it offers >1 million cycle lifetime, no contact bounce, and sub-ns switching control via 1OE/2OE-enabling software-defined signal routing in automated test systems.

Is the QS3VH384QG8 pin-compatible with other QuickSwitch® devices like the QS3VH244?

No, the QS3VH384QG8 is not pin-compatible with the QS3VH244 or other members of the QuickSwitch® family. It uses a unique 24-pin QSOP layout optimized for dual 5-bit banks (A0–A9/B0–B9 + 1OE/2OE), whereas the QS3VH244 is an octal non-inverting buffer in 20-pin SOIC. Pin count, function mapping, and package dimensions differ-PCB layout must be designed specifically for QS3VH384QG8.