Renesas IDTQS3257S18

Overview

IDTQS3257S18 from Renesas Electronics is a high-speed CMOS quad 2:1 multiplexer/demultiplexer with TTL-compatible control inputs, 5Ω typical ON resistance, zero propagation delay, and industrial temperature range (–40°C to +85°C). It enables bidirectional signal routing in video/audio switching, bus funneling, and hot-swap interfaces.

For engineers reviewing the IDTQS3257S18 datasheet, IDTQS3257S18 pinout, IDTQS3257S18 application, or IDTQS3257S18 equivalent, key selection criteria include its 5Ω switch R_ON, undervoltage clamp diodes on all I/O, V_CC-independent logic thresholds, and compatibility with 74F257/74FCT257 families in S1 package.

Technical Context

The IDTQS3257S18 implements four independent bidirectional analog switches using enhanced N-channel FETs with no inherent body diode to V_CC, enabling true rail-to-rail signal pass without forward conduction. Its control logic accepts TTL-level inputs (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V) and drives outputs into high-impedance state when disabled.

Each channel supports DC switch voltages from –0.5 V to +7 V across all terminals except V_CC, and exhibits <0.25 ns intrinsic propagation delay due to low R_ONC_IN time constant (C_IN ≤ 9 pF per channel), making it suitable for high-fidelity signal routing where timing integrity is critical.

Key Specifications

Pinout & Package

Package: S1 - 16-pin small outline IC (SOIC), RoHS-compliant, green molding compound.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74FCT257S18 and SN74CBT3257DBR, the IDTQS3257S18 delivers superior transient immunity, guaranteed industrial temperature performance, and lower intrinsic delay-making it optimal for mission-critical signal routing where reliability and timing transparency are non-negotiable.

Availability

IDTQS3257S18 is available at Aetrix Electronics and suitable for video switching, hot-swap interfaces, and industrial bus funneling requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for IDTQS3257S18 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 IoT applications.

The IDTQS3257S18 belongs to Renesas' QuickSwitch® family of high-speed bus switches, engineered specifically for low-latency, low-distortion signal routing in industrial control, test equipment, and multimedia systems.

FAQ

What is the maximum allowable input voltage on I/O pins of the IDTQS3257S18?

The IDTQS3257S18 supports DC input voltages from –0.5 V to +7 V on all switch and control pins except V_CC. This wide range accommodates undershoot transients down to –3 V (AC pulse ≤20 ns) and enables reliable voltage translation between 5 V and 3.3 V domains without external clamping. The device's integrated undershoot clamp diodes protect against negative excursions, making the IDTQS3257S18 robust in electrically noisy industrial environments.

Does the IDTQS3257S18 require external pull-up or pull-down resistors on its control inputs?

No, the IDTQS3257S18 does not require external biasing on its E (Enable) or S (Select) inputs. Its TTL-compatible control thresholds (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V) allow direct connection to standard 5 V logic outputs. Input leakage current is limited to ±1 μA, ensuring stable logic states without external resistors. This simplifies PCB layout and reduces BOM count in systems using the IDTQS3257S18 for bus switching or signal routing.

Can the IDTQS3257S18 be used for bidirectional 5 V to 3.3 V level translation?

Yes, the IDTQS3257S18 supports true bidirectional voltage translation between 5 V and 3.3 V logic domains. Its 5 Ω R_ON, rail-to-rail signal pass capability, and absence of body diodes to V_CC eliminate directionality constraints. When used with appropriate series termination, the IDTQS3257S18 maintains signal integrity for protocols like UART, SPI, or I²C without added propagation delay-making it ideal for mixed-voltage system interconnects.

What is the thermal performance of the IDTQS3257S18 at maximum operating temperature?

The IDTQS3257S18 is characterized for continuous operation from –40°C to +85°C with a maximum power dissipation of 0.5 W at T_A = 85°C. Its quiescent supply current is only 3 μA, and dynamic current scales linearly with toggle frequency (0.25 mA/MHz). With proper PCB copper pour and minimal trace length, the IDTQS3257S18 remains within safe junction temperature limits even in densely packed industrial modules.

Is the IDTQS3257S18 pin-compatible with standard 74-series logic devices?

Yes, the IDTQS3257S18 is pin-compatible with the 74F257, 74FCT257, and 74ALS/AS/LS257 quad 2:1 multiplexers in the S1 package. Pin assignments for I0A–I1D, YA–YD, S, E, V_CC, and GND match exactly, enabling drop-in replacement without PCB modification. However, the IDTQS3257S18 offers superior electrical performance-including lower R_ON, zero ground bounce, and integrated clamps-making it a functional and mechanical upgrade over legacy logic-based muxes.