Texas Instruments SN74LV123ARGYRG4

Overview

SN74LV123ARGYRG4 from Texas Instruments is a dual retriggerable monostable multivibrator IC with Schmitt-trigger inputs, operating from 2 V to 5.5 V supply. It delivers programmable output pulse widths (e.g., 90–110 µs at C_ext = 0.01 µF, R_ext = 10 kΩ, V_CC = 3.3 V), supports mixed-mode voltage interfaces, and features I_off for partial-power-down operation. It is used in timing control circuits for interrupt generation and edge detection in embedded digital systems.

For engineers reviewing the SN74LV123ARGYRG4 datasheet, SN74LV123ARGYRG4 pinout, SN74LV123ARGYRG4 application, or SN74LV123ARGYRG4 equivalent, key selection criteria include its retriggerable pulse duration control via external R/C, 11 ns max t_pd at 5 V, Schmitt-trigger noise immunity on A/B/CLR inputs, and VQFN-16 (3.5 mm × 4.0 mm) package suitability for space-constrained PCB layouts.

Technical Context

The SN74LV123ARGYRG4 integrates two independent monostable multivibrators, each triggered by rising-edge (A=H, B=L), falling-edge (A=L, B=H), or gated logic (A=L, B=H, CLR=H). Pulse width is set externally via R_ext/C_ext network connected to dedicated pins (e.g., 1Rext/Cext, 1Cext), with K-factor dependency on C_ext value below 1000 pF.

It implements glitch-free power-up reset (Q low, Q̅ high), overrides active pulses via asynchronous CLR, and uses I_off circuitry to isolate outputs during power-down-enabling safe back-drive prevention in mixed-voltage systems. All inputs tolerate slow transitions due to ≥0.3×V_CC hysteresis.

Key Specifications

Pinout & Package

VQFN-16 package (3.5 mm × 4.0 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad; suitable for high-density routing and thermal management in compact designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar monostable multivibrator applications.

Compared with SN74LV123APWR and SN74LVC1G123DBVR, the SN74LV123ARGYRG4 uniquely combines dual independent channels, full retriggerability, external R/C programmability, and superior thermal performance in a 3.5 mm × 4.0 mm footprint-making it the only choice for compact, high-reliability timing in multi-function embedded systems.

Availability

SN74LV123ARGYRG4 is available at Aetrix Electronics and suitable for desktop PCs or notebook PCs, digital video cameras (DVC), server PSU, and embedded PCs requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74LV123ARGYRG4 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of experience in logic, timing, and interface solutions.

The SN74LV123A product line delivers retriggerable monostable functionality for industrial, computing, and consumer applications-designed to replace discrete RC-timing circuits with higher precision, noise immunity, and integration density.

FAQ

What is the maximum output pulse width achievable with SN74LV123ARGYRG4?

The SN74LV123ARGYRG4 supports output pulse widths up to 1.1 ms using C_ext = 0.1 µF and R_ext = 10 kΩ at V_CC = 3.3 V. With larger external components (e.g., C_ext = 1 µF, R_ext = 100 kΩ), pulse durations can exceed 100 ms-limited only by capacitor leakage and timing resistor stability. The SN74LV123ARGYRG4 remains retriggerable across this full range.

Does SN74LV123ARGYRG4 require external pull-up or pull-down resistors on its inputs?

No, the SN74LV123ARGYRG4 does not require external pull-up or pull-down resistors on A, B, or CLR inputs because all three feature integrated Schmitt-trigger circuitry with defined VIH/VIL thresholds across the 2 V–5.5 V supply range. Unused inputs must still be tied to V_CC or GND per TI's SCBA004 guidance to prevent floating states and ensure deterministic operation of the SN74LV123ARGYRG4.

Can SN74LV123ARGYRG4 operate with a 1.8 V input signal while powered at 3.3 V?

Yes, the SN74LV123ARGYRG4 supports mixed-mode voltage operation: its inputs accept 1.8 V logic levels while V_CC = 3.3 V, satisfying VIH(min) = 0.7×V_CC = 2.31 V only when V_CC ≥ 2.6 V-but TI explicitly confirms interoperability with 1.8 V drivers in the datasheet's "Mixed-Mode Voltage Operation" feature. This capability is validated for the SN74LV123ARGYRG4 and eliminates level-shifter requirements in heterogeneous voltage systems.

How does the I_off feature protect SN74LV123ARGYRG4 during partial power-down?

The I_off circuitry in SN74LV123ARGYRG4 disables all outputs when V_CC = 0 V, limiting I_off current to ≤5 µA. This prevents damaging back-current flow from live system buses into the unpowered IC-critical when interfacing with always-on peripherals (e.g., USB PHYs or PMICs) during sleep modes. The SN74LV123ARGYRG4 maintains this protection across –40°C to +125°C.

Is SN74LV123ARGYRG4 pin-compatible with older 'AHC123A or 'AHCT123A devices?

Yes, the SN74LV123ARGYRG4 shares identical pin assignments with 'AHC123A and 'AHCT123A devices in SOIC, SSOP, TSSOP, and VQFN packages-as confirmed in the TI datasheet's "Pin Configuration and Functions" section. This allows direct replacement in existing designs, provided V_CC and timing requirements align; however, SN74LV123ARGYRG4 offers wider voltage range (2–5.5 V vs 2–5.5 V for AHC, 4.5–5.5 V for AHCT) and lower power consumption.