Diodes Incorporated 74HCT164T14-13

Overview

74HCT164T14-13 from Diodes Incorporated is an 8-bit serial-in/parallel-out edge-triggered shift register with asynchronous master reset, TTL-compatible inputs, Schmitt-trigger input action, and dual serial data inputs (DSA/DSB) logically ANDed for flexible enable/data control. It operates from 4.5V to 5.5V, delivers 4mA output drive at V_CC = 4.5V, and supports up to 55MHz clock frequency at 4.5V - used in PC peripheral interface expansion and optical drive control logic.

For engineers reviewing the 74HCT164T14-13 datasheet, 74HCT164T14-13 pinout, 74HCT164T14-13 application, or 74HCT164T14-13 equivalent, key selection considerations include its asynchronous MR pin behavior, dual-input serial gating logic, guaranteed setup/hold timing (12ns/4ns at 4.5V), TSSOP-14 package thermal profile, and HCT-family noise immunity in mixed-signal board environments.

Technical Context

The device implements eight cascaded D-type flip-flops with positive-edge clock (CP) triggering and asynchronous active-low master reset (MR). Serial data enters Q0 only when both DSA and DSB meet setup/hold requirements relative to CP's rising edge; their logical AND enables conditional data loading without external gates.

Each stage drives a buffered parallel output (Q0–Q7), with outputs capable of sourcing/sinking ±4mA at V_CC = 4.5V and exhibiting CMOS-level power consumption (<160μA ICC max over temperature). Input hysteresis (Schmitt trigger) ensures robust noise rejection on clock and data lines in electrically noisy systems.

Key Specifications

Pinout & Package

TSSOP-14 package: 4.9mm × 4.4mm body, 0.65mm pitch, exposed pad not present, moisture sensitivity level MSL3, rated for reflow peak ≤260°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit serial-in/parallel-out shift register applications.

Compared with SN74HCT164N and 74HC164PW, the 74HCT164T14-13 uniquely combines TSSOP-14 thermal efficiency, Schmitt-trigger noise immunity, and integrated asynchronous reset - making it optimal for space-constrained, electrically noisy industrial control applications requiring guaranteed startup state.

Availability

74HCT164T14-13 is available at Aetrix Electronics and suitable for PC peripheral interface expansion, optical drive control logic, and LED display driver applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HCT164T14-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The 74HCT164 belongs to Diodes' HCT logic family - engineered for TTL-compatible operation at 5V with CMOS power efficiency and enhanced noise immunity, targeting legacy system upgrades and mixed-voltage board interfaces.

FAQ

Can the 74HCT164T14-13 operate reliably at 3.3V?

No. The 74HCT164T14-13 is specified only for 4.5V to 5.5V operation. At 3.3V, VIH and VOH thresholds fall outside guaranteed logic levels, and propagation delay increases beyond specification. For 3.3V systems, consider the 74LVC164 or SN74LV164A, which are characterized down to 1.65V.

What happens if DSA and DSB are left floating?

Leaving DSA or DSB floating violates the recommended operating condition that unused inputs be tied to V_CC or GND. Floating inputs may oscillate due to noise, causing unintended data shifts or increased ICC. Always tie unused serial inputs to V_CC to disable that path and ensure predictable AND-gated behavior.

Is the MR pin truly asynchronous, and does it affect CP timing?

Yes. MR is fully asynchronous: asserting MR LOW immediately forces Q0–Q7 to LOW regardless of CP state or timing. Recovery requires MR to be HIGH for ≥16ns before the next CP rising edge (t_rec), but MR assertion itself imposes no minimum pulse width beyond standard logic low duration (≥10ns).

Does the TSSOP-14 package require special PCB layout considerations?

Yes. The 0.65mm pitch demands controlled-impedance routing, solder mask defined pads, and stencil aperture reduction (80% area ratio) to prevent bridging. Per Diodes AP02001, use 0.45mm X and 1.45mm Y pad dimensions with 0.65mm spacing; place 100nF ceramic decoupling capacitor within 5mm of V_CC and GND pins.