Overview of onsemi 74LVX4245MTCX

The onsemi 74LVX4245MTCX is an octal (8-bit) dual supply translating transceiver with 3-state outputs, designed for bidirectional voltage-level translation and data interfacing between devices operating at different voltage levels. It belongs to the LVX (Low Voltage eXtended) logic family and is ideally suited for applications that require data flow between two buses with differing power supplies, such as interfacing between 5 V and 3.3 V logic systems.

Functional Description

The 74LVX4245MTCX serves as a voltage level translator and octal bus transceiver. It can be used to transfer data between buses A and B, where A and B may be operating at different voltage levels. The direction of data flow is determined by the DIR (direction) pin, and the output enable (OE) pin controls the tri-state outputs. Each side of the transceiver is powered by a separate VCCA and VCCB supply rail, enabling true bidirectional level shifting.

* Translation Direction: A to B or B to A (controlled by DIR pin)
* Bus Width: 8-bit (octal)
* Output Enable: Active-low OE pin to enable or disable outputs
* Tri-State Outputs: Yes, when OE is high
* Dual Supply Operation: VCCA and VCCB can be independently powered

Key Electrical Specifications

The device supports a wide range of operating voltages and logic compatibility, enabling seamless interface between different logic families.

* VCCA Supply Voltage Range: 2.0 V to 3.6 V
* VCCB Supply Voltage Range: 3.0 V to 5.5 V
* Input Voltage Range: 0 V to 5.5 V (on both A and B side inputs)
* Output Voltage Range: 0 V to VCC (respective side)
* Input High Voltage (VIH):

* VCCA side: ≥ 0.7 × VCCA
* VCCB side: ≥ 2.0 V (for 5 V system)
* Input Low Voltage (VIL):

* VCCA side: ≤ 0.3 × VCCA
* VCCB side: ≤ 0.8 V

Drive and Load Characteristics

The 74LVX4245MTCX is capable of driving moderate capacitive and resistive loads with robust noise margins. It supports symmetrical output drive and can source or sink current, making it suitable for interfacing with various system buses.

* Output Drive Capability: ±24 mA at 5 V
* Maximum Load Capacitance: ~70 pF recommended for optimal signal integrity
* Output Leakage Current: ±1 µA (max, in high-impedance state)

Switching and Timing Characteristics

With its fast switching speed and low propagation delay, the device enables efficient operation in high-speed systems while maintaining logic integrity during level translation.

* Propagation Delay (tpd):

* 3 ns typical at 5 V, CL = 50 pF
* Output Transition Time (tTLH/tTHL):

* < 4 ns typical at 5 V
* Maximum Operating Frequency: ~100 MHz for standard loads

Power Characteristics

The 74LVX4245MTCX is designed to consume minimal static and dynamic power, especially when inputs are not switching or when outputs are disabled.

* Quiescent Supply Current (ICCT): < 10 µA per input
* ICC (Static Supply Current): ~20 µA typical
* Input Diode Clamp Current: ±20 mA max (with overvoltage)
* ESD Protection: >2 kV (Human Body Model)

Control Logic

The device features simple yet effective control logic for data direction and output enable functionality.

* DIR (Direction Control):

* High: Data flows from A → B
* Low: Data flows from B → A
* OE (Output Enable, active-low):

* Low: Enables outputs
* High: Outputs are in high-impedance (Hi-Z) state

This logic configuration enables easy interfacing with microcontrollers or FPGAs for managing data flow between system components.

Package and Mounting

The 74LVX4245MTCX is supplied in a TSSOP-24 package, which offers a compact footprint suitable for dense circuit boards in embedded systems.

* Package Type: TSSOP-24 (Thin Shrink Small Outline Package)
* Package Dimensions: Approx. 7.8 mm × 6.4 mm
* Pin Count: 24
* Mounting Style: Surface-mount technology (SMT)
* Moisture Sensitivity Level (MSL): Level 1
* RoHS Compliance: Yes

Thermal and Environmental Characteristics

The component is robust across a wide temperature range, making it suitable for consumer, industrial, and communication-grade systems.

* Operating Temperature Range: –40°C to +85°C
* Storage Temperature Range: –65°C to +150°C
* Thermal Resistance (θJA): ~100°C/W typical for TSSOP-24

Typical Applications

* Mixed-voltage communication between 3.3 V and 5 V systems
* Level translation for microcontrollers and peripheral interfaces
* Data buffers and bus isolation in embedded systems
* Consumer electronics and industrial automation
* Memory module interfaces and I/O expansion

Summary

The onsemi 74LVX4245MTCX is a robust, high-speed, dual-supply voltage translator and transceiver that enables bidirectional communication between buses operating at different logic levels. With flexible control, low power consumption, and fast switching, it is a dependable choice for systems requiring seamless voltage level interfacing across a variety of digital platforms. Its compact TSSOP-24 package and wide temperature range support make it ideal for integration into space- and performance-sensitive applications.