Texas Instruments TXB0304RSVR

Overview

TXB0304RSVR from Texas Instruments is a 4-bit bidirectional voltage translator with automatic direction sensing, designed for level-shifting between asymmetric I/O domains (e.g., 1.2 V ↔ 3.3 V). It supports fully independent supply rails (VCCA and VCCB from 0.9 V to 3.6 V), delivers ≤30 ns propagation delay at 1.8 V–3.6 V operation, consumes ≤5 μA per supply, and features VCC isolation and I_off partial-power-down protection. It is used in mixed-voltage microcontroller interfaces, FPGA I/O bridging, and portable system interconnects.

For engineers reviewing the TXB0304RSVR datasheet, TXB0304RSVR pinout, TXB0304RSVR application, or TXB0304RSVR equivalent, key selection criteria include bidirectional auto-sensing capability, 16-pin UQFN (2.6 mm × 1.8 mm) package compatibility, high-impedance OE control referenced to VCCA, and support for push-pull CMOS-not open-drain-signaling.

Technical Context

The TXB0304RSVR implements a passive-direction-detection architecture: no external direction control signal is required. Its I/O cells use edge-triggered one-shot circuits to dynamically enable PMOS/NMOS drive transistors during transitions, achieving low output impedance (5 Ω typical at VCCO ≥1.8 V) without latch-up risk. The device operates across full rail asymmetry-VCCA and VCCB may differ by up to 2.7 V-and maintains functional integrity during power sequencing due to VCC isolation logic.

It is explicitly incompatible with open-drain buses (e.g., I²C, 1-Wire) due to weak DC drive strength and absence of bus contention management. External pull-up/pull-down resistors must exceed 20 kΩ to avoid compromising VOH/VOL; design validation requires checking VIH/VIL margins against both source and sink voltage domains.

Key Specifications

Pinout & Package

TXB0304RSVR is housed in a 16-pin UQFN (RSV) package measuring 2.60 mm × 1.80 mm with 0.4 mm pitch and wettable flank terminations. The package supports automated optical inspection (AOI) and provides thermal performance of R_θJA = 131.7°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional voltage translation applications.

Compared with TXS0104RUTR and SN74AVC4T245RTER, TXB0304RSVR uniquely combines automatic direction detection, VCC isolation, and ultra-low quiescent current-making it optimal for compact, low-power, mixed-rail embedded systems where GPIO count and power budget are constrained.

Availability

TXB0304RSVR is available at Aetrix Electronics and suitable for mobile processor interface, FPGA-to-MCU bridging, and USB-C power delivery negotiation requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for TXB0304RSVR 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, embedded processing, and connectivity technologies, with over 50 years of innovation in precision analog and low-power digital solutions.

The TXB0304RSVR belongs to TI's TXB-series bidirectional voltage translators, engineered specifically for seamless, low-overhead level shifting in space-constrained, multi-voltage embedded systems-emphasizing automatic direction sensing and robust partial-power-down behavior.

FAQ

What is the maximum supported data rate for TXB0304RSVR under typical conditions?

The TXB0304RSVR supports up to 140 Mbps when operating with VCCA and VCCB ≥1.8 V and a 15 pF load. At lower voltages (e.g., 1.2 V), the maximum rate drops to 90 Mbps (CL = 30 pF) or 100 Mbps (CL = 50 pF). These values are measured per TI SCES831G Rev G and reflect actual switching performance-not theoretical limits-under defined test conditions.

Can TXB0304RSVR be used for I²C level translation?

No, TXB0304RSVR is not suitable for I²C. Its weak DC drive strength and lack of open-drain support cause bus contention and violate I²C electrical specifications. For I²C, TI recommends the TXS0104 series. TXB0304RSVR is strictly intended for push-pull CMOS interfaces such as GPIO, SPI, or parallel control lines.

How does the /OE pin on TXB0304RSVR function, and what is its voltage reference?

The /OE pin on TXB0304RSVR is active-low and referenced to VCCA. When pulled low, it places all A- and B-port I/Os into high-impedance state. To ensure safe power-up behavior, TI recommends tying /OE to GND via a pull-down resistor whose value depends on the driving source's current-sinking capability-typically 10 kΩ to 100 kΩ.

Does TXB0304RSVR support asymmetric supply voltages, and what is the maximum allowable difference?

Yes, TXB0304RSVR fully supports asymmetric operation: VCCA and VCCB may differ by up to 2.7 V (e.g., VCCA = 0.9 V, VCCB = 3.6 V). The device maintains correct logic translation and output drive regardless of which rail is higher, provided both remain within 0.9 V–3.6 V and meet recommended operating conditions per SCES831G Section 6.3.

What thermal performance can be expected from the TXB0304RSVR in its RSV package?

In the 16-pin RSV UQFN package, TXB0304RSVR has a junction-to-ambient thermal resistance (R_θJA) of 131.7°C/W under standard JEDEC JESD51-7 conditions. With proper PCB copper pour and two GND vias, real-world thermal rise remains below 15°C at full 10 μA ICCA+ICCB-making it suitable for thermally constrained modules without heatsinking.