Nexperia USA Inc. 74HCT193DB-Q100J

Overview

74HCT193DB-Q100 from Nexperia is a presettable synchronous 4-bit binary up/down counter with TTL-compatible inputs, asynchronous master reset (MR), asynchronous parallel load (PL), and dual terminal count outputs (TCU/TCD). It operates from 4.5 V to 5.5 V across −40 °C to +125 °C, supports automotive-grade timing control in engine management and body electronics, and features edge-triggered CPU/CPD clocks with predictable state transitions on LOW-to-HIGH edges.

For engineers reviewing the 74HCT193DB-Q100 datasheet, 74HCT193DB-Q100 pinout, 74HCT193DB-Q100 application, or 74HCT193DB-Q100 equivalent, this device delivers deterministic bidirectional counting, cascading capability via active-low TCU/TCD outputs, and AEC-Q100 Grade 1 qualification for under-hood and ADAS subsystems requiring robust digital timing functions.

Technical Context

The 74HCT193DB-Q100 implements four edge-triggered D-type flip-flops with synchronous counting logic gated by CPU and CPD inputs-only one clock may be HIGH at any time to ensure unambiguous direction control. Its asynchronous PL and MR inputs override all clock activity, enabling immediate preset or zero-clear independent of clock phase.

Terminal count outputs TCU and TCD are active-LOW and replicate the respective clock waveform at terminal states (1111 for TCU, 0000 for TCD), allowing direct connection to higher-order stage clocks without external logic. The device uses standard CMOS fabrication with TTL-level input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5–5.5 V) and exhibits propagation delays as low as 15 ns (CPU to Qn, VCC = 4.5 V, 25 °C).

Key Specifications

Pinout & Package

74HCT193DB-Q100 is supplied in SO16 (SOT109-1) package: plastic small outline, 16 leads, 3.9 mm body width, gull-wing leads, JEDEC MS-012 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-bit synchronous up/down counter applications.

Compared with 74HC193DB-Q100 and SN74LS193N, the 74HCT193DB-Q100 uniquely balances TTL-level input compatibility, AEC-Q100 Grade 1 reliability, and low-power CMOS efficiency-making it optimal for new automotive designs requiring drop-in replaceability with legacy 74LS logic while meeting modern thermal and longevity requirements.

Availability

74HCT193DB-Q100 is available at Aetrix Electronics and suitable for engine control units, transmission control modules, and ADAS radar subsystems requiring stable component supply with guaranteed automotive-grade traceability and long-term lifecycle support.

Supply support for 74HCT193DB-Q100 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 logic, discrete, and MOSFET solutions, with leadership in automotive-qualified components.

The 74HCT193DB-Q100 belongs to Nexperia's AEC-Q100-qualified HC/HCT logic family, engineered specifically for automotive signal conditioning, timing, and control functions where deterministic behavior and extended temperature operation are mandatory.

FAQ

What is the minimum pulse width required on CPU or CPD for reliable counting?

The minimum HIGH or LOW pulse width on CPU or CPD is 10 ns at VCC = 4.5 V (−40 °C to +85 °C), per Table 9. This ensures proper internal flip-flop triggering without race conditions. Shorter pulses risk metastability or missed counts, especially in noisy automotive environments where signal integrity must be preserved through proper PCB layout and termination.

Can TCU and TCD be used simultaneously to drive separate higher-order counters?

Yes-TCU and TCD are electrically independent, active-LOW outputs that can concurrently drive different downstream stages. For example, TCU may clock an up-counter for speed accumulation while TCD clocks a down-counter for timeout monitoring. Each output replicates its associated clock edge at terminal state, enabling fully autonomous multistage operation without external gating logic.

How does the device behave if both CPU and CPD are held HIGH?

If both CPU and CPD are HIGH simultaneously, the counter enters an undefined state per the function table: no count action occurs, but outputs remain latched at their last valid value. This condition violates the "only one clock HIGH" requirement and must be avoided in design-use combinational logic or MCU firmware to enforce mutual exclusion between CPU and CPD activation.

Is the parallel load function truly asynchronous with respect to clock edges?

Yes-the PL input is fully asynchronous: when PL is driven LOW, D0–D3 appear on Q0–Q3 within tpd (max 69 ns at VCC = 4.5 V, −40 °C to +125 °C), regardless of CPU/CPD state or timing. This allows immediate reinitialization mid-operation, such as correcting encoder drift in real time without waiting for clock alignment or reset sequencing.