Renesas QS3VH2245PAG

Overview

QS3VH2245PAG from Renesas Electronics (formerly IDT) is an 8-bit high-bandwidth bus switch IC with N-channel FET architecture, 25Ω typical ON resistance, 1.35ns max propagation delay at 3.3V, and 5V-tolerant I/Os operating from 2.3V–3.6V VCC. It enables bidirectional rail-to-rail signal switching (0–5V) with no added ground bounce, ideal for hot-swap interfaces in telecom backplanes.

For engineers reviewing the QS3VH2245PAG datasheet, QS3VH2245PAG pinout, QS3VH2245PAG application, or QS3VH2245PAG equivalent, key selection criteria include its LVTTL-compatible OE control, 4pF typical I/O capacitance, -40°C to +85°C industrial temperature range, and QSOP-20 green package compatibility with high-speed data isolation requirements.

Technical Context

The QS3VH2245PAG implements eight independent N-channel FET switches with no parasitic diode to VCC, enabling true power-off isolation and eliminating DC paths to VCC or GND. Its charge-pump-assisted gate drive supports 5V signal pass-through even when VCC = 2.5V or 3.3V.

Switching is controlled solely by a single active-low Output Enable (OE) input compatible with LVTTL logic levels. Propagation delay is dominated by RC time constant (RON × CL), not internal logic - resulting in near-zero added delay and minimal signal distortion across all eight channels.

Key Specifications

Pinout & Package

QS3VH2245PAG is housed in a 20-pin QSOP (Green) package, 7.2mm × 4.4mm body, 0.65mm pitch. Pin 1 is top-left corner (notch-marked), with NC on Pin 1 and GND on Pin 10.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74CBT3245APWR and PI3CH485LE, the QS3VH2245PAG uniquely combines 5V I/O tolerance, power-off isolation, and industrial temperature rating - making it the only option among the three qualified for hot-swap backplane and mixed-voltage analog-digital interface designs.

Availability

QS3VH2245PAG is available at Aetrix Electronics and suitable for hot-swap backplane interfaces, low-distortion analog routing, and ATM switching nodes requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for QS3VH2245PAG 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 QS3VH2245PAG belongs to Renesas' QuickSwitch® bus switch product line, engineered specifically for high-fidelity, low-latency signal routing in live-insertion and mixed-voltage system architectures.

FAQ

What is the maximum signal voltage the QS3VH2245PAG can pass when VCC = 3.3V?

The QS3VH2245PAG can pass signals from 0V to 5V regardless of VCC level - including when VCC = 3.3V. This is enabled by its internal charge pump that biases the N-channel FET gates above the signal rail. The device maintains 5V tolerance on all A/B I/O pins in both ON and OFF states, supporting interoperability between 3.3V logic and legacy 5V peripherals without external level shifters. This capability is explicitly confirmed in the Absolute Maximum Ratings table and Functional Description section of the official datasheet.

Does the QS3VH2245PAG require external pull-up or pull-down resistors on the OE pin?

No, the QS3VH2245PAG does not require external biasing on the OE pin. Its OE input is LVTTL-compatible with guaranteed VIH ≥ 2.0V and VIL ≤ 0.8V at VCC = 2.7–3.6V, allowing direct connection to standard CMOS or FPGA outputs. Internal circuitry ensures clean threshold detection without floating-state risk. The datasheet specifies ±1μA max input leakage current, confirming stable logic interpretation across temperature and voltage extremes - so OE may be driven actively high/low without external resistors.

Can the QS3VH2245PAG be used to isolate power domains during system sleep mode?

Yes, the QS3VH2245PAG supports safe power-domain isolation during sleep mode. Its N-channel FET structure has no parasitic diode to VCC, and IOFF leakage is specified at ±1μA when VCC = 0V and VIN/VOUT = 0–5V. This ensures no DC path exists between powered and unpowered sections, preventing backfeed or unintended wake-up. The device remains functional as long as OE is held high (disabled), maintaining >10⁹Ω off-state impedance - a key feature validated in the "Isolation under power-off conditions" statement in the Features section.

What is the thermal performance of the QS3VH2245PAG in continuous operation?

The QS3VH2245PAG is characterized for continuous operation from -40°C to +85°C ambient, with no derating required within this industrial temperature range. Its maximum power dissipation is limited by ICCQ (4mA max) and dynamic switching current (ICCD ≤ 12mA at 20MHz OE toggle). Thermal resistance θJA for the QSOP-20 package is approximately 120°C/W, yielding <1.5°C junction rise above ambient at full load - well within silicon limits. No heatsink or airflow is needed for typical bus-switching duty cycles.

How does the QS3VH2245PAG compare to mechanical relays in hot-swap applications?

The QS3VH2245PAG replaces mechanical relays by delivering nanosecond switching (tPZL/tPLZ < 9ns), zero contact wear, and silent operation - while adding 5V tolerance, 4pF capacitance, and integrated undershoot protection. Unlike relays, it requires no coil drive circuitry or debounce logic, reduces PCB area by >95%, and achieves MTBF >10⁹ hours. Its bidirectional, low-ROn behavior matches relay performance for signal integrity, but with superior reliability and integration density - as highlighted in the Applications section's "Replaces mechanical relay" bullet.