Nexperia USA Inc. HEF40373BT,652

Overview

HEF40373BT,652 from Nexperia is an 8-bit transparent latch IC with 3-state buffered outputs, designed for bus interface and data hold functions in digital systems. It features Schmitt-trigger hysteresis on the latch enable (E) input for noise immunity, operates across 5 V/10 V/15 V supply rails, and supports −40 °C to +85 °C ambient range. Its high-current outputs drive capacitive loads up to 50 pF with propagation delays as low as 36 ns (VDD = 15 V).

For engineers reviewing the HEF40373BT,652 datasheet, HEF40373BT,652 pinout, HEF40373BT,652 application, or HEF40373BT,652 equivalent, this device serves as a static CMOS octal latch for bidirectional bus isolation, address/data latching in microcontroller peripherals, and legacy TTL-compatible logic interfacing where 3-state control and wide-voltage operation are required.

Technical Context

The HEF40373BT,652 implements eight independent D-type transparent latches with synchronous enable control via the E input and global 3-state output control via EO. Each latch follows input data when E is HIGH and holds the last valid state on the HIGH-to-LOW transition of E, meeting set-up (10 ns min at VDD = 15 V) and hold (3 ns min) timing requirements.

Its output stage uses complementary MOS transistors with bipolar-assisted sourcing capability, enabling ±25 mA output clamping current and high-impedance OFF-state leakage < ±1.6 μA. The Schmitt-trigger E input provides 320 mV hysteresis, allowing robust operation with slow-rising signals and reducing susceptibility to ground bounce or EMI.

Key Specifications

Pinout & Package

HEF40373BT,652 is housed in a plastic small outline package (SO20), 20-pin, 7.5 mm body width (SOT163-1), with gull-wing leads and standard JEDEC MS-013 footprint compatibility.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal transparent latch applications.

Compared with HEF40373BT,652, the 74HC373 offers superior speed in low-voltage domains but sacrifices noise margin and voltage flexibility, while CD4099BE trades transparency for addressability-making HEF40373BT,652 uniquely suited for wide-supply, noise-prone bus latching where deterministic edge-triggered hold is unnecessary.

Availability

HEF40373BT,652 is available at Aetrix Electronics and suitable for industrial control panels, legacy bus interface modules, and microcontroller-based instrumentation requiring stable component supply across extended temperature and voltage ranges.

Supply support for HEF40373BT,652 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 specializing in high-performance logic, discrete, and MOSFET solutions, with manufacturing rooted in process reliability and automotive-grade quality systems.

The HEF40373BT,652 belongs to Nexperia's legacy CMOS logic family, engineered for backward compatibility with 4000-series devices while delivering enhanced noise immunity, wider voltage operation, and industrial temperature resilience.

FAQ

What is the minimum pulse width required on the E input to reliably latch data?

The minimum E pulse width is 10 ns at VDD = 15 V, 30 ns at VDD = 10 V, and 60 ns at VDD = 5 V, as specified in the datasheet's limiting values table. This ensures sufficient time for internal latch nodes to stabilize before the HIGH-to-LOW transition completes the capture window.

Can HEF40373BT,652 drive a 100 pF bus capacitance?

No - the datasheet specifies dynamic characteristics up to 50 pF load capacitance. At 100 pF, propagation delays increase significantly (e.g., tPHL extrapolates to ~100 ns at VDD = 15 V), and output transition times exceed guaranteed limits. External series termination or buffer staging is recommended for >50 pF loads.

Is the EO pin compatible with 3.3 V logic levels when VDD = 15 V?

Yes - the EO input threshold is referenced to VDD, with VIH ≥ 11.0 V and VIL ≤ 4.0 V at VDD = 15 V. A 3.3 V signal falls below VIL and will be interpreted as LOW, enabling 3.3 V microcontrollers to safely control the 15 V device's output state via open-drain or level-shifted interface.

Does HEF40373BT,652 require external pull-up resistors on unused inputs?

Yes - per datasheet Section 9 footnote [1], all unused inputs (D0–D7, E, EO) must be connected to VDD, VSS, or another driven input. Floating CMOS inputs cause increased supply current, potential oscillation, and ESD vulnerability; 10 kΩ pull-ups to VDD are commonly used for unconnected Dn or EO lines.