NXP Semiconductors 74HCT9115D,118

Overview

74HCT9115D,118 from Nexperia is a nine-channel non-inverting Schmitt trigger buffer with open-drain N-channel MOSFET outputs, designed for noise-immune signal conditioning and level shifting in 5 V digital systems. It features 9 independent input/output pairs, Schmitt-trigger inputs with 0.44 V typical hysteresis at 5 V, propagation delay of 18 ns (typ) at VCC = 4.5 V, and operates across −40 °C to +125 °C. It is used in industrial sensor interface circuits where slow or noisy signals require clean digital conversion.

For engineers reviewing the 74HCT9115D,118 datasheet, 74HCT9115D,118 pinout, 74HCT9115D,118 application, or 74HCT9115D,118 equivalent, key selection criteria include open-drain output compatibility with mixed-voltage buses, Schmitt-trigger noise immunity for low-slew-rate inputs, level-shifting capability up to VOmax, and guaranteed operation over extended temperature range without external hysteresis components.

Technical Context

The 74HCT9115D,118 implements nine independent non-inverting Schmitt-trigger buffers using high-speed Si-gate CMOS technology compliant with JEDEC Standard No. 7A and TTL-compatible input thresholds. Each channel accepts standard 5 V TTL-level inputs (VIH = 2.0 V min, VIL = 0.8 V max) and delivers open-drain outputs capable of sinking ≥4 mA at VOL ≤ 0.4 V.

Its Schmitt-trigger inputs provide 0.44 V typical hysteresis (VT+ = 1.2 V, VT− = 0.76 V at VCC = 4.5 V), enabling reliable digitization of slowly rising/falling analog or mechanical switch signals. The absence of internal VCC clamping diodes allows output voltage translation between 0–5.5 V domains when paired with external pull-ups.

Key Specifications

Pinout & Package

74HCT9115D,118 is housed in a 20-pin SO20 (Small Outline) package per JEDEC MS-013, 7.5 mm body width, 1.27 mm pitch. Pin 10 is GND; Pin 20 is VCC; Pins 1–9 are inputs A0–A8; Pins 11–19 are outputs Y0–Y8 (Y0 = Pin 11, Y8 = Pin 19).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HCT9115D,118, the 74HCT14D,653 offers fewer channels and inverted outputs, limiting direct substitution in 9-signal non-inverting paths; the SN74LVTH162244DGGR lacks Schmitt inputs and open-drain capability, making it unsuitable for noise rejection or level translation - both require redesign rather than drop-in replacement.

Availability

74HCT9115D,118 is available at Aetrix Electronics and suitable for industrial sensor interfaces, legacy system upgrades, wired-OR bus implementations, and level-shifting I/O expanders requiring stable component supply across extended temperature ranges.

Supply support for 74HCT9115D,118 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 global semiconductor expert focused on high-volume, high-reliability discrete, logic, and power MOSFET solutions for automotive, industrial, and computing markets.

The 74HCT9115D,118 belongs to Nexperia's 74HCT logic family, engineered for robust noise immunity and seamless integration into 5 V TTL-compatible systems requiring Schmitt-trigger signal conditioning and flexible output interfacing.

FAQ

What is the maximum output sink current specification for the 74HCT9115D,118?

The 74HCT9115D,118 guarantees a minimum output sink current of 4 mA per channel at VOL ≤ 0.4 V when VCC = 4.5 V and Tamb = 25 °C. This rating ensures reliable driving of standard TTL loads and compatibility with common pull-up resistor values (e.g., 10 kΩ to 5 V yields ~0.5 mA). Absolute maximum sink current is limited by total package power dissipation and thermal derating above 25 °C.

Does the 74HCT9115D,118 support level shifting between 5 V and 3.3 V logic domains?

Yes, the 74HCT9115D,118 supports level shifting because its open-drain outputs are not clamped to VCC. When Yn is pulled up to 3.3 V (instead of VCC), the 74HCT9115D,118 can safely drive 3.3 V logic inputs while accepting 5 V TTL-level inputs on A0–A8. This configuration avoids overvoltage stress and eliminates need for external translators - confirmed by Nexperia's application guidance for mixed-voltage bus interfacing.

Is the 74HCT9115D,118 pin-compatible with the 74HC9115D variant?

Yes, the 74HCT9115D,118 is pin-compatible with the 74HC9115D variant - both share identical SO20 pinout, terminal functions, and logic behavior. The key difference lies in input threshold compatibility: 74HCT9115D,118 uses TTL-compatible thresholds (VIH = 2.0 V min), while 74HC9115D requires CMOS-level inputs (VIH ≈ 0.7 × VCC). Electrical substitution is possible only if source logic meets the respective input voltage requirements.

What is the typical hysteresis voltage of the 74HCT9115D,118 at 5 V supply?

The typical hysteresis voltage (VT+ − VT−) of the 74HCT9115D,118 is 0.44 V at VCC = 4.5 V, with VT+ = 1.2 V and VT− = 0.76 V. At VCC = 5.5 V, hysteresis increases to 0.8 V max. This wide hysteresis band provides strong noise immunity against glitches up to ±220 mV on input signals, making the 74HCT9115D,118 ideal for mechanical switch debouncing and slow RC waveforms.

Can the 74HCT9115D,118 be used without external pull-up resistors?

No, the 74HCT9115D,118 cannot produce a valid HIGH logic level without external pull-up resistors on Y0–Y8 outputs. Its open-drain structure only sinks current; the output floats in the OFF state (high-impedance). A pull-up resistor to a defined voltage rail (e.g., 3.3 V or 5 V) is mandatory to establish a logic HIGH. Typical values range from 1 kΩ (for speed) to 10 kΩ (for low power), depending on bus capacitance and rise-time requirements.