Renesas QS3244SOG8

Overview

QS3244SOG8 from Renesas Electronics is an 8-bit high-speed CMOS bus switch with TTL-compatible inputs, 5Ω ON resistance, zero propagation delay, and industrial temperature range (–40°C to +85°C). It functions as a bidirectional signal path controller for hot-swappable backplanes and voltage-level isolated data buses.

For engineers reviewing the QS3244SOG8 datasheet, QS3244SOG8 pinout, QS3244SOG8 application, or QS3244SOG8 equivalent, key selection criteria include its 5Ω switch R_ON, dual independent enable control (1G/2G), ±1μA off-state leakage, undershoot clamp diodes on all I/Os, and compatibility with 74FCT244/74F244 logic families.

Technical Context

The QS3244SOG8 implements eight independent N-channel FET switches with no inherent body diode to V_CC, enabling true bidirectional signal flow without forward-bias risk. Each channel features undriven Hi-Z isolation when disabled and supports DC switching up to ±7V across A/Y terminals.

Its dual enable architecture (1G and 2G) allows independent control of two 4-bit groups (1A1–1Y4 and 2A1–2Y4), matching the functional partitioning of 74'244 drivers. Switch turn-on/off delays are specified at 0.5–5.6 ns, with propagation delay bounded only by RC time constant (R_ON × C_L) rather than internal logic.

Key Specifications

Pinout & Package

QS3244SOG8 is packaged in a 20-pin QSOP (Quarter Size Outline Package), RoHS-compliant and green-processed, with 0.65 mm lead pitch and JEDEC MO-137AC footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74FCT244SOG8 and SN74CBT3244PWR, the QS3244SOG8 uniquely delivers zero propagation delay, true bidirectionality without direction pins, and integrated undershoot clamps - making it optimal for high-integrity hot-swap and low-jitter clock gating where signal transparency is mandatory.

Availability

QS3244SOG8 is available at Aetrix Electronics and suitable for hot-swappable backplane interfaces, voltage-translated data buses, and low-power system isolation requiring stable component supply across industrial temperature ranges.

Supply support for QS3244SOG8 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 QS3244SOG8 belongs to Renesas' QuickSwitch® bus switch product line, engineered specifically for high-speed, low-latency signal routing in hot-plug, level-translation, and power-gated systems.

FAQ

What is the maximum allowable voltage on A/Y pins of the QS3244SOG8?

The QS3244SOG8 supports DC voltages from –0.5 V to +7 V on all A and Y pins, independent of V_CC. This enables safe operation during hot-swap events with transient undershoot down to –3 V (AC, ≤20 ns pulse width), thanks to integrated clamp diodes. The specification is validated across the full industrial temperature range.

Does the QS3244SOG8 require external pull-up or pull-down resistors on its enable pins?

No, the QS3244SOG8 does not require external biasing on 1G or 2G pins. Its control inputs have ±1 μA max leakage over temperature, and logic thresholds are TTL-compatible (V_IL ≤ 0.8 V, V_IH ≥ 2 V). Direct connection to MCU GPIO or logic gates is sufficient; no pull resistors are needed for stable enable/disable operation.

Can the QS3244SOG8 be used for clock signal switching without introducing jitter?

Yes, the QS3244SOG8 is suitable for clock gating because it introduces no added propagation delay beyond the RC time constant of its 5Ω R_ON and load capacitance - typically <0.25 ns at 50 pF. With zero ground bounce and no internal logic, it preserves clock edge integrity and minimizes jitter accumulation in synchronous systems.

Is the QS3244SOG8 pin-compatible with standard SOIC-20 packages?

QS3244SOG8 uses a QSOP-20 package (JEDEC MO-137AC), which has a 0.65 mm lead pitch and smaller body than standard SOIC-20 (1.27 mm pitch). It is not mechanically pin-compatible with SOIC-20 footprints. However, it shares identical pin numbering and function mapping with SOIC- and TSSOP-packaged variants of the same device family.

What is the thermal performance of the QS3244SOG8 at maximum ambient temperature?

At TA = +85°C, the QS3244SOG8 has a maximum power dissipation of 0.5 W. Its thermal resistance (θ_JA) in QSOP-20 is approximately 120°C/W, resulting in a junction temperature rise of ~60°C above ambient - well within the 150°C max storage limit. No heatsink is required for typical bus-switching duty cycles.