Renesas QS3VH257QG

Overview

QS3VH257QG from Renesas Electronics (formerly IDT) is a quad 2:1 multiplexer/demultiplexer bus switch with N-channel FET architecture, 4 Ω typical ON resistance, <0.2 ns propagation delay, 5 V tolerance in both ON/OFF states, and rail-to-rail analog switching (0–5 V). It serves as a high-bandwidth signal path selector in hot-swap-capable backplane interfaces.

For engineers reviewing the QS3VH257QG datasheet, QS3VH257QG pinout, QS3VH257QG application, or QS3VH257QG equivalent, key selection criteria include its LVTTL-compatible control inputs, 500 MHz bandwidth, -40°C to +85°C industrial temperature range, bidirectional zero-delay operation, and isolation under power-off conditions.

Technical Context

The QS3VH257QG implements four independent 2:1 analog switches controlled by a shared active-low Enable (E) and active-high Select (S) input. Each channel passes signals bidirectionally with no added ground bounce and exhibits flat R_ON across the full 0–5 V input range.

Its N-channel FET design eliminates parasitic diodes to V_CC, enabling true 5 V tolerance regardless of V_CC (2.3–3.6 V), isolation when unpowered, and no DC path to supply or ground - critical for live-insertion systems and mixed-voltage domain bridging.

Key Specifications

Pinout & Package

QS3VH257QG is packaged in a 16-pin QSOP (Green, RoHS-compliant) with 0.65 mm pitch and 5.3 mm × 10.2 mm body size.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2:1 analog mux/demux applications.

Compared with SN74CBT3257PWR and ADG732BRUZ, the QS3VH257QG uniquely combines 5 V I/O tolerance, sub-0.2 ns delay, and industrial temperature rating - making it the only option for robust hot-swap and ATM 155 Mbps applications requiring guaranteed signal integrity across voltage domains.

Availability

QS3VH257QG is available at Aetrix Electronics and suitable for hot-swappable backplane interfaces, ATM 155 Mbps switching, and mixed-voltage domain bridging requiring stable component supply and long-term industrial lifecycle support.

Supply support for QS3VH257QG 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, and infrastructure markets.

The QS3VH257QG belongs to Renesas' QuickSwitch® family of high-bandwidth bus switches, designed specifically for zero-delay signal routing in live-insertion systems, telecom switching fabrics, and mixed-voltage interface bridging.

FAQ

What is the maximum signal voltage the QS3VH257QG can pass while powered from 3.3 V?

The QS3VH257QG supports rail-to-rail analog switching from 0 V to 5 V regardless of V_CC level. When powered from 3.3 V, it safely passes 5 V signals in both ON and OFF states due to its N-channel FET architecture with no parasitic diode to V_CC. This enables direct interfacing with legacy 5 V peripherals without level-shifting circuitry - a key capability confirmed in the Absolute Maximum Ratings and DC Electrical Characteristics tables of the official QS3VH257QG datasheet.

Does the QS3VH257QG require external pull-up or pull-down resistors on its control inputs?

No, the QS3VH257QG does not require external biasing on S or E inputs. Its LVTTL-compatible control inputs have guaranteed VIH (2.0 V min at V_CC ≥ 2.7 V) and VIL (0.8 V max) thresholds, and input leakage is limited to ±1 μA across the industrial temperature range. Direct connection to FPGA or ASIC GPIOs meeting LVTTL logic levels is sufficient - verified in the DC Electrical Characteristics section of the QS3VH257QG datasheet.

Can the QS3VH257QG be used in analog audio signal routing applications?

Yes, the QS3VH257QG is suitable for analog audio routing due to its 4 Ω typical R_ON, flat resistance vs. voltage profile, 4 pF I/O capacitance, and rail-to-rail 0–5 V operation. These characteristics minimize insertion loss, harmonic distortion, and crosstalk in line-level (≤2 V_PP) audio paths. However, for microphone-level or high-fidelity DAC/ADC interfaces, dedicated audio switches with lower THD specifications may be preferred - as noted in the Applications section of the QS3VH257QG datasheet.

What is the thermal performance of the QS3VH257QG in continuous operation?

The QS3VH257QG has no specified thermal resistance (θ_JA) in its datasheet, but its quiescent ICCQ is only 2 mA (typ.) and dynamic supply current remains below 8 mA even at 20 MHz toggle frequency. With 4 Ω R_ON and typical load currents under 30 mA per channel, power dissipation stays well below 10 mW per switch - ensuring junction temperatures remain within the -40°C to +85°C industrial range without heatsinking. This is validated in the Power Supply Characteristics and DC Electrical Characteristics sections of the QS3VH257QG datasheet.

Is the QS3VH257QG pin-compatible with earlier IDT QS3VH257 variants in SOIC or TSSOP packages?

Yes, the QS3VH257QG (QSOP package) shares identical pinout, function table, and electrical behavior with the SOIC (QS3VH257PG) and TSSOP (QS3VH257DG) variants. All three share the same 16-pin configuration, terminal assignments, and logic mapping per the Pin Configuration diagram and Function Table in the QS3VH257QG datasheet. Package differences affect only mechanical footprint and thermal characteristics - not signal routing or interface compatibility.