Texas Instruments 74LVC1G123DCURE4

Overview

74LVC1G123DCURE4 from Texas Instruments is a single retriggerable monostable multivibrator with Schmitt-trigger inputs, designed for 1.65 V to 5.5 V operation. It delivers programmable output pulse durations (ns to ms range) via external R/C network, supports mixed-mode voltage translation, and features glitch-free power-up reset and Ioff for partial-power-down protection. It is used in switch debouncing, timing control, and edge-sensitive event conditioning in consumer digital systems.

For engineers reviewing the 74LVC1G123DCURE4 datasheet, 74LVC1G123DCURE4 pinout, 74LVC1G123DCURE4 application, or 74LVC1G123DCURE4 equivalent, this page provides verified functional identity, validated VSSOP-8 pin mapping, confirmed retriggerable monostable behavior, real-world timing constraints (e.g., 8 ns max tpd at 3.3 V), and two technically documented alternative parts with explicit functional and application differences.

Technical Context

The 74LVC1G123DCURE4 implements a CMOS-based retriggerable monostable architecture where output pulse width is determined by external Rext and Cext components connected to dedicated timing pins (Rext/Cext and Cext). Triggering occurs on either rising edge at B (with A low), falling edge at A (with B high), or rising edge at CLR (with A low and B high).

Schmitt-trigger inputs on A and B provide ≥0.3 V hysteresis at 3.3 V, enabling jitter-free response to slow-rising/falling signals. The device supports down-translation from 5.5 V inputs to VCC levels as low as 1.65 V and includes Ioff circuitry that disables outputs during power-down to prevent back-drive current.

Key Specifications

Pinout & Package

74LVC1G123DCURE4 is packaged in an 8-pin VSSOP (DCU) with nominal body size 2.30 mm × 2.00 mm and 0.5 mm pitch. This ultra-thin, leaded package supports automated assembly and offers superior thermal resistance (RθJA = 227°C/W) versus SSOP.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G123DBVR and MC74VHC1G123DTT1G, the 74LVC1G123DCURE4 uniquely combines VSSOP-8 pin integrity with full Ioff support, 2000 V HBM ESD, and 8 ns propagation speed - making it the only option qualified for retriggerable timing in thermally constrained, hot-pluggable, or safety-aware embedded systems.

Availability

74LVC1G123DCURE4 is available at Aetrix Electronics and suitable for switch debouncing, power-on reset sequencing, edge-sensitive event capture, and variable-duration pulse generation requiring stable component supply across industrial, consumer, and computing platforms.

Supply support for 74LVC1G123DCURE4 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 focused on analog, embedded processing, and connectivity technologies, serving industrial, automotive, and communications markets with high-reliability silicon solutions.

The SN74LVC1G123 product line delivers compact, low-power retriggerable monostables for precise hardware timing in space- and power-constrained digital systems - targeting mechanical interface conditioning and deterministic event synchronization.

FAQ

What is the minimum external timing capacitor value supported by the 74LVC1G123DCURE4?

The 74LVC1G123DCURE4 supports external timing capacitors down to 10 pF, as validated in TI's switching characteristics tables (Section 5.8) and typical application curves (Figure 8-2). At 10 pF with Rext = 1 kΩ and VCC = 3.3 V, the device achieves output pulse durations as short as ~100 ns - sufficient for high-speed edge conditioning and narrow pulse generation in the 74LVC1G123DCURE4 design.

Can the 74LVC1G123DCURE4 operate with a 1.65 V supply voltage while maintaining full timing accuracy?

Yes - the 74LVC1G123DCURE4 is fully specified from 1.65 V to 5.5 V per Section 5.3 of the datasheet. At 1.65 V, propagation delay increases to 18.5 ns (max, CL = 15 pF), and output drive strength reduces to ±4 mA, but all timing functions including retriggering, CLR override, and Schmitt-trigger hysteresis remain operational and characterized across –40°C to +125°C for the 74LVC1G123DCURE4.

Does the 74LVC1G123DCURE4 require external pull-up resistors on its A, B, or CLR inputs?

No - the 74LVC1G123DCURE4 does not require external pull-ups on A, B, or CLR. Its inputs are CMOS-compatible with defined VIH/VIL thresholds across VCC range (e.g., VIH = 0.65×VCC min at 1.65 V), and all unused inputs must be tied to VCC or GND per TI application report SCBA004. External pull-ups add unnecessary leakage and noise sensitivity - the 74LVC1G123DCURE4 operates reliably with direct GPIO or switch connections.

How does the Ioff feature of the 74LVC1G123DCURE4 protect against back-drive current?

The Ioff circuitry in the 74LVC1G123DCURE4 actively disables all outputs when VCC = 0 V, limiting Ioff current to ±10 µA (Section 5.5). This prevents current from flowing backward into the unpowered IC from externally driven buses or powered peripherals - a critical safeguard during live insertion, partial power-down, or system-level power sequencing where subsystems power up/down asynchronously. This behavior is guaranteed across temperature for the 74LVC1G123DCURE4.

What is the maximum duty cycle achievable with the 74LVC1G123DCURE4 in retriggerable mode?

The 74LVC1G123DCURE4 supports up to 100% duty cycle in retriggerable mode, as explicitly stated in its Features section and validated by functional testing in TI's characterization lab. Continuous retriggering - e.g., applying periodic pulses to A or B faster than the programmed pulse width - sustains Q high indefinitely, enabling use as a gated oscillator or latched enable signal without external feedback, a capability confirmed for the 74LVC1G123DCURE4.