NXP Semiconductors 74HCT273DB,118

Overview

74HCT273DB,118 from Nexperia is an octal positive-edge-triggered D-type flip-flop with asynchronous master reset (MR), designed for synchronous data latching in digital logic systems. It operates at 4.5 V to 5.5 V, delivers 16 ns typical propagation delay (CP to Qn) at VCC = 4.5 V, supports -40 °C to +125 °C industrial temperature range, and features TTL-compatible inputs for direct interfacing with legacy logic families. It is used in address/data register staging, bus interface synchronization, and control state retention in microcontroller peripheral interfaces.

For engineers reviewing the 74HCT273DB,118 datasheet, 74HCT273DB,118 pinout, 74HCT273DB,118 application, or 74HCT273DB,118 equivalent, this device is selected when precise edge-triggered storage with guaranteed reset behavior, low-power CMOS operation, and robust noise immunity are required in 20-pin SOIC-based digital control paths - especially where TTL-level input compatibility and wide supply tolerance simplify mixed-logic system integration.

Technical Context

The 74HCT273DB,118 implements eight independent D-type flip-flops sharing a common clock (CP) and active-low master reset (MR). Its TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5 V) ensure reliable interfacing with 5 V TTL outputs without level-shifting. The device uses standard CMOS silicon with clamp diodes on all inputs, enabling safe operation with current-limiting resistors when driven from voltages exceeding VCC.

It exhibits deterministic timing: set-up time (tsu) of 12 ns and hold time (th) of 3 ns at VCC = 4.5 V/CL = 50 pF, and maximum operating frequency of 30 MHz under those conditions. All outputs switch with matched transition times (tt = 7–15 ns) and drive ±4.0 mA loads while maintaining VOH ≥ 3.98 V and VOL ≤ 0.26 V.

Key Specifications

Pinout & Package

74HCT273DB,118 is supplied in a plastic small outline package (SO20, SOT163-1) with 20 leads and 7.5 mm body width. Pin 1 is marked by a notch or dot; the package is lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type flip-flop applications.

Compared with SN74HCT273N and 74HCT374PW,118, the 74HCT273DB,118 provides optimal balance of compact SO20 packaging, pure latch functionality, and industrial temperature support - making it preferred for cost-sensitive, high-reliability register applications where tri-state capability or through-hole mounting are unnecessary.

Availability

74HCT273DB,118 is available at Aetrix Electronics and suitable for microcontroller bus interfaces, industrial I/O expansion, memory address latching, and digital control state storage requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HCT273DB,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 delivering high-performance, reliable logic, analog, and MOSFET solutions optimized for efficiency and miniaturization in industrial, automotive, and consumer applications.

The 74HCT273DB,118 belongs to Nexperia's 74HCT logic family - engineered for seamless interoperability between TTL and CMOS systems while maintaining low power consumption and robust noise immunity in harsh environments.

FAQ

What is the maximum clock frequency supported by the 74HCT273DB,118?

The 74HCT273DB,118 supports a maximum clock frequency of 30 MHz at VCC = 4.5 V and CL = 50 pF, as specified in the dynamic characteristics table. At VCC = 5.0 V with reduced load (CL = 15 pF), it achieves up to 36 MHz. These values assume proper signal integrity, adequate decoupling, and adherence to set-up/hold timing margins.

Can the 74HCT273DB,118 operate reliably at 3.3 V supply?

No - the 74HCT273DB,118 is specified only for 4.5 V to 5.5 V operation. Its TTL-compatible inputs require VIH ≥ 2.0 V, which is met at 5 V, but at 3.3 V the input threshold compliance degrades and output drive falls outside guaranteed specifications. For 3.3 V systems, use the 74LVC273 or 74ALVC273 instead.

How does the master reset (MR) interact with the clock signal?

The MR input is asynchronous and dominant: when MR is LOW, all Qn outputs force LOW immediately, overriding any ongoing clock activity or data input states. MR has no dependency on CP timing - it takes effect as soon as the input crosses its VIL threshold, with typical MR→Qn propagation delay of 23 ns at VCC = 4.5 V.

Is the 74HCT273DB,118 pin-compatible with the 74HC273DB,118?

Yes - both share identical pinout, package (SO20/SOT163-1), and functional diagram. However, the 74HC273DB,118 uses CMOS-level inputs (VIH = 3.15 V min at VCC = 4.5 V), whereas the 74HCT273DB,118 uses TTL-level inputs (VIH = 2.0 V min). Swapping them may cause logic misreads if driving sources lack sufficient voltage swing.