Texas Instruments SN74LV540APWR

Overview

SN74LV540APWR from Texas Instruments is an octal inverting buffer/driver with 3-state outputs, designed for bus line driving and memory address register buffering in 2 V to 5.5 V systems. It features dual active-low output enables (OE1/OE2), supports mixed-mode voltage operation, provides Ioff for partial-power-down mode, and delivers ≤8.5 ns propagation delay at 5 V - enabling reliable signal isolation in industrial and medical data interfaces.

For engineers reviewing the SN74LV540APWR datasheet, SN74LV540APWR pinout, SN74LV540APWR application, or SN74LV540APWR equivalent, this device is selected for low-ringing bus interface tasks requiring 3-state control, overvoltage-tolerant inputs (up to 5.5 V), and stable operation across –40°C to 125°C ambient conditions.

Technical Context

The SN74LV540APWR implements eight independent inverting buffers, each with a two-input AND gate logic structure for 3-state control: outputs enter high-impedance when either OE1 or OE2 is high. Its CMOS design ensures balanced drive strength (±16 mA at 5 V), while slow edge rates minimize output ringing and undershoot/overshoot - confirmed by VOHV >2.3 V and VOLP <0.8 V at 3.3 V.

Input voltage tolerance extends to 5.5 V regardless of VCC, enabling down-translation from higher-voltage domains. The Ioff feature guarantees isolation between powered and unpowered sections, preventing current backflow when VCC = 0 V - critical for hot-swap and power sequencing in multi-rail systems.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.50 mm × 4.40 mm body, 0.65 mm pitch, exposed pad optional, RoHS-compliant NIPDAU finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC540APWR and 74ACT540SCX, the SN74LV540APWR uniquely balances 2–5.5 V operation, 5.5 V input tolerance, and Ioff - making it the sole option for new designs requiring interoperability across voltage domains and safe power sequencing.

Availability

SN74LV540APWR is available at Aetrix Electronics and suitable for industrial transport control, patient monitoring interface, and wireless infrastructure baseband applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LV540APWR 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 delivering analog and embedded processing solutions, with over 90 years of innovation in precision analog, power management, and logic devices.

The SN74LV540APWR belongs to TI's LV family of low-voltage logic ICs, engineered specifically for mixed-signal systems requiring robust noise immunity, wide supply range, and seamless integration across heterogeneous voltage domains.

FAQ

What is the maximum propagation delay of the SN74LV540APWR at 3.3 V operation?

The SN74LV540APWR has a maximum propagation delay (tpd) of 9.5 ns at VCC = 3.3 V, CL = 15 pF, and TA = –40°C to 125°C. This value is specified in Section 6.7 of the datasheet and reflects worst-case timing under full industrial temperature range - critical for verifying setup/hold margins in synchronous bus designs using the SN74LV540APWR.

Does the SN74LV540APWR support partial-power-down mode, and how is it implemented?

Yes, the SN74LV540APWR supports partial-power-down mode via its Ioff feature. When VCC = 0 V, Ioff limits input/output leakage to ≤5 µA, preventing current backflow between powered and unpowered sections. This behavior is guaranteed across –40°C to 125°C and is explicitly tested per JEDEC JESD78, ensuring safe operation during power sequencing in systems using the SN74LV540APWR.

Can the SN74LV540APWR interface directly with 5 V logic inputs while operating at 3.3 V VCC?

Yes, the SN74LV540APWR accepts input voltages up to 5.5 V regardless of VCC level - including when VCC = 3.3 V. This overvoltage tolerance is specified in Section 6.3 (VI absolute max = 7 V) and validated in mixed-mode operation testing, allowing direct connection to 5 V microcontrollers or FPGAs without external level shifters in designs using the SN74LV540APWR.

What is the recommended bypass capacitor for the VCC pin of the SN74LV540APWR?

Texas Instruments recommends a 0.1 µF ceramic capacitor placed adjacent to the VCC pin (Pin 20) of the SN74LV540APWR. This value is specified in Section 9.3 for single-supply devices and minimizes high-frequency switching noise. For optimal performance, mount the capacitor with shortest possible trace length and connect directly to the local ground plane - a practice validated in layout guidelines for the SN74LV540APWR.

How does the dual output-enable architecture of the SN74LV540APWR improve system-level bus control?

The SN74LV540APWR features two independent active-low output enables (OE1 and OE2). Either high disables all eight outputs - enabling flexible bus arbitration: OE1 can control one functional group (e.g., sensor interface), OE2 another (e.g., display control), or both used together for full isolation. This architecture reduces external logic count and improves fault containment in systems built around the SN74LV540APWR.