Renesas QS34X245Q3G8

Overview

QS34X245Q3G8 from Renesas Electronics is a 32-bit high-speed CMOS bus switch with flow-through pinout, zero propagation delay, 5Ω typical ON-resistance at 5V, and industrial temperature range (–40°C to +85°C), used for hot-swappable 32-bit data path isolation and voltage translation between 5V and 3.3V domains.

For engineers reviewing the QS34X245Q3G8 datasheet, QS34X245Q3G8 pinout, QS34X245Q3G8 application, or QS34X245Q3G8 equivalent, key selection criteria include bidirectional switching capability, TTL-compatible control inputs, undershoot clamp diodes on all I/Os, and MilliPaQ™ 80-pin package compatibility for dense PCB layouts.

Technical Context

The QS34X245Q3G8 implements 32 independent N-channel FET switches with no inherent body diode to V_CC, enabling true bidirectional signal flow without DC blocking. Each switch is controlled by one of four independent OE pins (OE1–OE4), allowing segmented bus enable/disable per 8-bit group.

It operates with V_CC = 5.0V ±5%, supports DC input voltages from –0.5V to +7V, and delivers pass voltage ≥3.7V at V_IN = V_CC = 5V. Switch turn-on/off delays are specified up to 5.6ns and 5.2ns respectively, while propagation delay is effectively zero-limited only by RC time constant of R_ON and load capacitance.

Key Specifications

Pinout & Package

QS34X245Q3G8 is housed in an 80-pin MilliPaQ™ package - a fine-pitch, thermally enhanced, surface-mount solution with exposed thermal pad and flow-through pin arrangement minimizing signal crosstalk and routing complexity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3245APM and PI3CH400QE, the QS34X245Q3G8 uniquely combines 32-bit density, integrated undershoot protection, and zero-delay performance in a single industrial-grade package - making it optimal for space-constrained, hot-pluggable backplane designs requiring full-width isolation.

Availability

QS34X245Q3G8 is available at Aetrix Electronics and suitable for hot-swapping, voltage translation, and bus isolation applications requiring stable component supply, long-term industrial lifecycle support, and RoHS-compliant packaging.

Supply support for QS34X245Q3G8 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 QS34X245Q3G8 belongs to Renesas' QuickSwitch® MultiWidth™ bus switch family, engineered specifically for high-density, low-latency signal routing in industrial computing and modular system architectures.

FAQ

What is the operating voltage range for QS34X245Q3G8?

The QS34X245Q3G8 operates with a nominal V_CC of 5.0V ±5%, supporting industrial applications from –40°C to +85°C. Its absolute maximum ratings allow DC input voltages from –0.5V to +7V on all terminals except V_CC, and it tolerates AC pulses down to –3V for ≤20ns. This wide margin ensures robustness in noisy or transient-prone environments where the QS34X245Q3G8 is deployed.

Does QS34X245Q3G8 support bidirectional signal flow?

Yes, the QS34X245Q3G8 supports fully bidirectional signal flow between its A and B ports. Each of the 32 channels uses an enhanced N-channel FET with no inherent body diode to V_CC, eliminating unidirectional conduction paths. This architecture allows seamless data transfer in either direction - for example, from a 5V processor to a 3.3V peripheral or vice versa - without requiring direction-control logic, making the QS34X245Q3G8 ideal for flexible bus topologies.

How many independent enable controls does QS34X245Q3G8 provide?

The QS34X245Q3G8 provides four independent active-low Output Enable inputs: OE1, OE2, OE3, and OE4. Each controls a distinct 8-bit segment (OE1 → A0–A7/B0–B7, OE2 → A8–A15/B8–B15, etc.), enabling granular power and signal gating. This segmentation allows partial bus isolation - for instance, disabling only memory-mapped I/O while keeping control registers active - a capability central to the QS34X245Q3G8's role in modular system design.

Is QS34X245Q3G8 compatible with 3.3V logic control signals?

No, the QS34X245Q3G8 requires TTL-compatible control inputs: V_IH ≥ 2.0V and V_IL ≤ 0.8V under 5V V_CC. While it can translate data between 5V and 3.3V domains on its A/B ports, its OE pins are not 3.3V-tolerant for logic-high recognition. Driving OE directly from a 3.3V microcontroller may result in undefined behavior; a level shifter or buffer is recommended. This constraint is explicitly defined in the QS34X245Q3G8's DC electrical characteristics table.

What package type is used for QS34X245Q3G8?

The QS34X245Q3G8 is packaged in an 80-pin MilliPaQ™ - a proprietary Renesas surface-mount package featuring a flow-through pinout, fine pitch, and exposed thermal pad. It is RoHS-compliant, green-processed, and optimized for high-density PCB layouts with minimal signal stubs. The MilliPaQ™ footprint differs from standard QFP or TSSOP packages, so the QS34X245Q3G8 requires dedicated land pattern design per Renesas' packaging documentation.