Nexperia USA Inc. HEF40373BT,653

Overview

HEF40373BT,653 from Nexperia is an 8-bit transparent latch with 3-state buffered outputs in SO20 package, designed for bus interface isolation and data hold in digital systems. It features hysteresis on the latch enable (E) input for noise immunity, Schmitt-trigger action for tolerance to slow signal edges, and operates across 3 V to 15 V supply range with guaranteed performance from −40 °C to +85 °C. Used in industrial control backplanes and legacy microprocessor data buses.

For engineers reviewing the HEF40373BT,653 datasheet, HEF40373BT,653 pinout, HEF40373BT,653 application, or HEF40373BT,653 equivalent, key selection considerations include 3-state output timing (tPHZ/tPLZ ≤ 50 ns at 15 V), latch enable hysteresis (320 mV), static operation support, and compatibility with 5 V/10 V/15 V logic families in non-automotive embedded systems.

Technical Context

The HEF40373BT,653 implements eight independent D-type latches with shared E (latch enable) and EO (output enable) controls. Each latch follows input Dn when E is HIGH and holds data on the HIGH-to-LOW transition of E, meeting set-up (tsu = 10 ns min at 15 V) and hold (th = 3 ns min at 15 V) requirements.

Its 3-state outputs are driven by a dual-transistor (P-channel MOS + NPN bipolar) stage enabling high-current sinking (IOL = 30 mA at 15 V) and sourcing (IOH = −20 mA at 15 V), while hysteresis on E improves noise margin by 320 mV and supports slow-rising clock or control signals.

Key Specifications

Pinout & Package

HEF40373BT,653 is housed in a plastic small outline package (SO20, SOT163-1) with 20 leads, 7.5 mm body width, and standard 1.27 mm lead pitch. Pin 1 is marked by a bevelled corner or index notch per JEDEC MS-013.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal transparent latch with 3-state output applications.

Compared with HEF40373BT,653, the 74HC373PW,118 offers superior speed at lower voltages but sacrifices noise immunity and wide-supply flexibility, while CD4099BE replaces transparency with addressability-making it unsuitable for synchronous bus capture without added control logic.

Availability

HEF40373BT,653 is available at Aetrix Electronics and suitable for industrial PLC backplanes, legacy microprocessor bus interfaces, and test equipment signal routing requiring stable component supply across extended temperature and voltage ranges.

Supply support for HEF40373BT,653 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 delivering high-performance, reliable logic, discrete, and MOSFET solutions with focus on efficiency, reliability, and sustainability.

The HEF40373BT,653 belongs to Nexperia's legacy 4000B-series CMOS logic family, engineered for robust operation in industrial control, instrumentation, and retro-computing applications where wide supply range and noise immunity are critical.

FAQ

What is the minimum supply voltage required for guaranteed operation of HEF40373BT,653?

The HEF40373BT,653 is specified down to 3 V per Table 5 (Recommended Operating Conditions). At 3 V, static parameters including VIH (≥2.1 V), VIL (≤0.9 V), VOH (≥2.9 V), and VOL (≤0.15 V) remain valid across −40 °C to +85 °C, and dynamic timing (e.g., tPHL ≤ 300 ns) is maintained with appropriate load capacitance derating.

Can HEF40373BT,653 drive a 100 pF bus capacitance reliably at 15 V?

Yes. The output stage delivers 30 mA sink and 20 mA source current at 15 V, and dynamic characteristics (Table 7) specify propagation delays extrapolated up to CL = 100 pF. Measured tTHL/tTLH increase linearly with CL (Figure 10), remaining within 30 ns at 15 V/100 pF - well within typical industrial bus timing margins.

Is the E input truly Schmitt-triggered, and how does that affect system design?

Yes - the E input incorporates Schmitt-trigger action with 320 mV hysteresis (Table 9), confirmed in Section 1 (General Description) and Table 6 (Static Characteristics). This allows reliable operation with slow-rising enable signals (e.g., from RC networks or mechanical switches) and rejects noise spikes smaller than ±160 mV, eliminating need for external debounce or filtering in harsh environments.

Does HEF40373BT,653 support hot insertion or live bus swapping?

No. While its 3-state outputs (enabled by EO) allow safe bus disconnection during steady-state operation, the device lacks Ioff protection or power-off isolation. Applying VDD before VSS or inserting into a live bus with mismatched supply sequencing may cause latch-up or excessive current per Absolute Maximum Ratings (Table 4), so hot-swap use requires external protection circuitry.