NXP Semiconductors 74LVT126DB,118

Overview

74LVT126DB,118 from Nexperia is a 3.3 V quad non-inverting buffer with 3-state outputs, designed for bus interface applications in mixed-voltage systems. It features bus-hold inputs (eliminating external pull-ups), IOFF partial power-down protection, and 5.5 V-tolerant inputs. Each buffer delivers ±32 mA/±64 mA (LOW/HIGH) drive into 5 V buses, operating across -40 °C to +85 °C.

For engineers reviewing the 74LVT126DB,118 datasheet, 74LVT126DB,118 pinout, 74LVT126DB,118 application, or 74LVT126DB,118 equivalent, key selection criteria include 3-state timing (tPZH ≤ 5.4 ns @ 3.3 V), overvoltage input tolerance, bus-hold current specs (IBHL = 75–150 μA), and SO14 package compatibility with legacy 74-series footprints.

Technical Context

The 74LVT126DB,118 implements BiCMOS logic architecture to achieve high-speed propagation (tPLH/tPHL ≤ 3.9 ns @ 3.3 V) while maintaining TTL-level compatibility and 5 V bus interfacing capability. Its IOFF circuit actively disables outputs during power-down, blocking backflow current when VCC = 0 V and VI/VO = 0–4.5 V.

Bus-hold functionality maintains valid logic states on unused inputs without external resistors-IBHL = 75–150 μA at VI = 0.8 V and IBHH = −75 to −150 μA at VI = 2.0 V (VCC = 3 V). Input clamping voltage (VIK = −1.2 to −0.9 V) and ESD robustness (HBM > 2000 V, CDM > 1000 V) support live insertion and harsh industrial environments.

Key Specifications

Pinout & Package

74LVT126DB,118 is packaged in SO14 (SOT108-1): plastic small outline, 14-lead, 3.9 mm body width, standard 1.27 mm lead pitch. Pin 1 is index-marked; pin 7 = GND; pin 14 = VCC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 3-state buffer applications.

Compared with 74LVT126DB,118, the 74LVT125DB,118 offers identical performance with inverted logic - useful in differential or complemented bus designs - while the SN74LVC126APW trades off IOFF, bus-hold, and drive strength for lower cost and broader low-voltage compatibility, limiting its use in industrial hot-swap or mixed-voltage environments.

Availability

74LVT126DB,118 is available at Aetrix Electronics and suitable for industrial backplane interfaces, hot-swappable module control, legacy system voltage translation, and high-density logic interface applications requiring stable component supply, long-term lifecycle assurance, and SO14 footprint compatibility.

Supply support for 74LVT126DB,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 focused on high-volume, high-reliability logic, analog, and MOSFET solutions for automotive, industrial, and consumer markets.

The 74LVT series targets high-speed, mixed-voltage bus interface applications - specifically engineered for 3.3 V systems interfacing with 5 V infrastructure while supporting hot-swap, partial power-down, and bus-hold requirements.

FAQ

What is the maximum input voltage the 74LVT126DB,118 can tolerate while powered at 3.3 V?

The device accepts input voltages up to +5.5 V regardless of VCC level - confirmed by Table 4 (VI max = +7.0 V under clamping conditions) and Table 5 (VI max = +5.5 V under recommended operation). This enables safe interfacing with 5 V logic without external level shifters or clamping diodes.

Does the 74LVT126DB,118 support live insertion when VCC is unpowered?

Yes - its IOFF circuitry actively disables outputs and limits power-off leakage current to ±100 μA when VCC = 0 V and I/O pins are biased from 0 V to 4.5 V (Table 6). This prevents damaging backflow current, satisfying JEDEC JESD78 Class II latch-up requirements (>500 mA) and enabling true hot-swap capability.

How does bus-hold functionality eliminate the need for external pull-up resistors?

Each input has integrated bus-hold circuitry that sources or sinks 75–150 μA to maintain the last-valid logic state: IBHL holds LOW inputs near 0 V; IBHH holds HIGH inputs near VCC. This eliminates external 10 kΩ resistors on unused pins - verified in Table 6 and Section 1 General Description.

What is the worst-case 3-state disable time (tPLZ) for the 74LVT126DB,118 at 3.3 V?

The maximum tPLZ (LOW-to-OFF-state propagation delay) is 5.5 ns at VCC = 3.3 V ± 0.3 V and Tamb = −40 °C to +85 °C, per Table 7. This ensures rapid bus release during dynamic reconfiguration, minimizing contention windows in multi-master systems.