NXP Semiconductors 74HC9115D/S400118

Overview

74HC9115D/S400118 from Nexperia is a 9-bit Schmitt trigger buffer IC with open-drain outputs, designed for noise-immune signal conditioning and level-shifting in industrial control and bus interface circuits. It operates from 2.0 V to 6.0 V, features nine independent input/output channels (A0–A8 / Y0–Y8), supports -40 °C to +125 °C ambient range, and delivers 10 ns propagation delay at 6.0 V.

For engineers reviewing the 74HC9115D/S400118 datasheet, 74HC9115D/S400118 pinout, 74HC9115D/S400118 application, or 74HC9115D/S400118 equivalent, key selection criteria include Schmitt-trigger hysteresis (0.5–1.1 V), open-drain output drive capability (±25 mA), input clamp diode support for overvoltage tolerance, and SO20 (SOT163-1) package compatibility with legacy 74HC logic footprints.

Technical Context

The 74HC9115D/S400118 implements nine independent Schmitt-trigger input buffers feeding open-drain NMOS outputs - no internal pull-ups. Each channel exhibits asymmetric hysteresis (VT+ = 2.30–4.20 V, VT− = 1.80–3.30 V at VCC = 6.0 V), enabling robust rejection of slow-rising or noisy signals. Input clamp diodes allow safe interfacing to voltages exceeding VCC when used with external current-limiting resistors.

Its static behavior follows a simple function table: low input drives output low; high input places output in high-impedance (Z) state. Dynamic performance is load-dependent: propagation delay ranges from 10 ns (VCC = 6.0 V, CL = 50 pF) to 165 ns (VCC = 2.0 V, CL = 50 pF), with transition times under 19 ns at full supply.

Key Specifications

Pinout & Package

74HC9115D/S400118 is housed in a plastic small outline package (SO20), SOT163-1 variant, with 20 leads and 7.5 mm body width. Pin 1 is index-marked; pins are arranged in dual rows with GND (pin 10) and VCC (pin 20) positioned for optimal decoupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schmitt-trigger buffer applications.

Compared with SN74LVCH16T245DGGR and 74LVC1G17GW,125, the 74HC9115D/S400118 uniquely combines nine independent Schmitt-trigger channels, open-drain outputs, and industrial temperature range in a single SO20 package - making it optimal for deterministic, noise-immune parallel signal conditioning where channel count and ruggedness outweigh bidirectionality or ultra-low voltage support.

Availability

74HC9115D/S400118 is available at Aetrix Electronics and suitable for industrial control panels, factory automation I/O modules, and embedded sensor hubs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HC9115D/S400118 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

Nexperia is a leading Dutch semiconductor manufacturer specializing in high-volume logic, discrete, and MOSFET components with emphasis on reliability, efficiency, and automotive-grade quality.

The 74HC9115D/S400118 belongs to Nexperia's 74HC logic family, engineered for robust signal integrity in electrically noisy environments - particularly targeting industrial automation, building controls, and legacy system upgrades where Schmitt-trigger noise rejection and open-drain flexibility are critical.

FAQ

What is the maximum sink current per output pin on the 74HC9115D/S400118?

The 74HC9115D/S400118 supports a maximum output current of ±25 mA per Yn pin under recommended operating conditions. This rating applies when VO is between -0.5 V and VCC + 0.5 V. Exceeding this value risks thermal overstress or parametric shift. For continuous 25 mA operation, ensure PCB copper area and ambient temperature remain within derating limits specified in the datasheet - especially above 109 °C where total power dissipation decreases linearly at 12.3 mW/K.

Does the 74HC9115D/S400118 require external pull-up resistors on its outputs?

Yes, the 74HC9115D/S400118 requires external pull-up resistors on all Y0–Y8 outputs because they are open-drain. Without pull-ups, outputs remain floating in the HIGH state. Typical values range from 1 kΩ (for fast rise times and higher power) to 10 kΩ (for low power and slower edges). The choice depends on bus capacitance, required edge rate, and supply voltage - e.g., a 4.7 kΩ resistor yields ~1.5 V/ns rise time with 50 pF load at 5 V.

Can the 74HC9115D/S400118 interface safely with input signals exceeding VCC?

Yes, the 74HC9115D/S400118 includes input clamp diodes that allow safe interfacing with signals up to VCC + 0.5 V or down to -0.5 V, provided external current-limiting resistors restrict IIK to ±20 mA maximum. This feature enables direct connection to 5 V sensors in a 3.3 V system, for example - but resistor value must be calculated using (Vin − VCC − 0.7 V)/20 mA to avoid diode damage.

What is the hysteresis voltage range of the 74HC9115D/S400118 across its full supply range?

The hysteresis voltage (VH = VT+ − VT−) of the 74HC9115D/S400118 ranges from 0.5 V to 1.1 V depending on VCC: at VCC = 2.0 V, VH = 0.4 V (min); at VCC = 4.5 V, VH = 0.75 V (typ); at VCC = 6.0 V, VH = 0.5–1.1 V (min–max). This wide hysteresis window ensures reliable noise rejection across all supported supply voltages, especially critical in motor control feedback or relay monitoring applications.

Is the 74HC9115D/S400118 pin-compatible with other 74HC-series 20-pin buffers?

No, the 74HC9115D/S400118 has a unique pinout optimized for 9-bit parallel operation: inputs A0–A8 occupy pins 1–9, outputs Y0–Y8 occupy pins 11–19, with GND at pin 10 and VCC at pin 20. It is not pin-compatible with standard 74HC244, 74HC245, or 74HC541 devices - those allocate inputs/outputs differently and lack Schmitt-trigger inputs. Always verify against the SOT163-1 pin diagram before PCB layout.