TXB0108PWR - 8-Bit Bidirectional Level Shifter 100Mbps | TI
MPN: TXB0108PWR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.55 | $0.55 |
| 10 | $0.44 | $4.40 |
| 100 | $0.32 | $32.00 |
| 500 | $0.25 | $125.00 |
| 1,000 | $0.18 | $180.00 |
Drop-in alternatives for TXB0108PWR β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
TXB0108QPWRQ1
β Drop-Inβ In Stock
$0.68 / Unit
View Datasheet βTXS0108EPWR
β Drop-Inβ In Stock
$0.42 / Unit
View Datasheet βTXS0108EQPWRQ1
β Drop-Inβ In Stock
$0.39 / Unit
View Datasheet βNTS0108BQ/PW
β Drop-Inπ Reference alternative (not in catalog)
TXB0108PWR Maximum Ratings & Electrical Characteristics
| Function | 8-Bit Bidirectional Voltage-Level Translator |
| Direction Control | Auto-direction sensing (no DIR pin) |
| A Port Supply (VCCA) | 1.2 V to 3.6 V |
| B Port Supply (VCCB) | 1.65 V to 5.5 V |
| Supply Constraint | VCCA <= VCCB |
| Max Data Rate | 100 Mbps |
| Channels | 8 |
| ESD Protection | +/-15 kV (HBM) |
| VCC Isolation | Yes - outputs Hi-Z if either VCC at GND |
| Operating Temperature | -40C to +85C |
| Package | TSSOP-20 (PW) |
| Mounting Type | Surface Mount |
| Driver Type | Push-pull CMOS only (internal 4 kOhm series resistors) |
| Ioff Support | Yes (partial-power-down) |
| RoHS Status | Compliant |
TXB0108PWR Pin Configuration
| Pin 1 | A1 β A-port data 1 (1.2V-3.6V domain) |
| Pin 2 | VCCA β A-port supply, 1.2V to 3.6V |
| Pin 3 | GND β Ground |
| Pin 4 | A2 β A-port data 2 |
| Pin 5 | A3 β A-port data 3 |
| Pin 6 | A4 β A-port data 4 |
| Pin 7 | A5 β A-port data 5 |
| Pin 8 | A6 β A-port data 6 |
| Pin 9 | A7 β A-port data 7 |
| Pin 10 | A8 β A-port data 8 |
| Pin 11 | B8 β B-port data 8 (1.65V-5.5V domain) |
| Pin 12 | B7 β B-port data 7 |
| Pin 13 | B6 β B-port data 6 |
| Pin 14 | B5 β B-port data 5 |
| Pin 15 | B4 β B-port data 4 |
| Pin 16 | B3 β B-port data 3 |
| Pin 17 | B2 β B-port data 2 |
| Pin 18 | OE β Output enable, active high; tie low to Hi-Z all outputs |
| Pin 19 | VCCB β B-port supply, 1.65V to 5.5V |
| Pin 20 | B1 β B-port data 1 |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
TXB0108PWR is suitable for 6 applications: Microcontroller-to-Sensor Interface, SD Card Level Shifting, UART/SPI Signal Translation, FPGA Configuration and IO Expansion, Industrial Automation Control Boards, Automotive Electronics (via Q1 variant).
Microcontroller-to-Sensor Interface
The TXB0108PWR is ideal for connecting a 1.8V MCU (A port) to 3.3V sensors (B port) because its A port accepts 1.2V-3.6V supplies and its auto-direction sensing removes DIR-pin firmware overhead. Placed directly on the SPI or I2C-adjacent data lines, it delivers up to 100 Mbps for push-pull signals. Since the device only supports push-pull drivers, I2C pins should instead route through the TXS0108E; digital SPI, UART, and GPIO lines benefit from the one-shot edge acceleration and +/-15 kV ESD robustness against handling transients.
Recommended
SD Card Level Shifting
SD/SDIO interfaces frequently require 1.8V-to-3.3V or 3.3V-to-1.8V translation between host controller and card. The TXB0108PWR's 100 Mbps rate comfortably covers high-speed SD clock and data lines, while its eight channels map naturally onto CMD plus four data lines with spare capacity. The one-shot architecture preserves fast clock edges, and the VCC isolation feature puts all outputs in Hi-Z if either rail collapses - protecting the card during hot-insertion. Keep trace capacitance below ~70 pF to retain full timing margin.
Recommended
UART/SPI Signal Translation
For mixed-voltage communication links, the TXB0108PWR translates UART TX/RX and SPI MOSI/MISO/SCK/CS signals between 1.8V, 2.5V, 3.3V, and 5V domains. The 100 Mbps capability far exceeds typical UART baud rates and covers SPI clocks up to tens of MHz. Auto-direction sensing means each channel adapts automatically to data direction without MCU intervention. Designers must ensure both ends drive push-pull; a pull-down on unused channels avoids floating-node oscillation, since the internal 4 kOhm resistors leave lines weakly biased.
Recommended
FPGA Configuration and IO Expansion
FPGAs and CPLDs commonly run at 1.8V core-bank voltages while peripherals demand 3.3V signaling. The TXB0108PWR bridges eight such signals per device, and multiple units scale to wider buses. The +/-15 kV ESD rating protects front-panel and connector-adjacent lines, while the Ioff partial-power-down feature ensures Hi-Z outputs when FPGA banks are unpowered - preventing back-powering. Its 100 Mbps speed covers configuration clocks and general-purpose banks; heavy bus loads above 70 pF should be buffered for timing margin.
Recommended
Industrial Automation Control Boards
Industrial controllers mix 5V legacy logic with modern 3.3V or 1.8V processors. The TXB0108PWR's wide B-port range (1.65V-5.5V) and -40C to +85C temperature rating suit factory-floor environments, while auto-direction sensing simplifies bidirectional control and status lines without firmware direction management. The VCC isolation feature guarantees Hi-Z outputs during brownouts of either rail, a key requirement in multi-supply industrial panels. Designers should note its weak drive (internal 4 kOhm) makes it unsuitable for long cables or high-fanout loads; use it for short board-level traces.
Recommended
Automotive Electronics (via Q1 variant)
The automotive-qualified TXB0108QPWRQ1 shares the TXB0108PWR die and TSSOP-20 footprint, allowing one PCB design to serve both standard and AEC-Q100 builds. Automotive ECUs frequently translate between 1.8V/3.3V MCUs and 5V sensors or actuators; the +/-15 kV ESD protection adds robustness against load-dump-adjacent transients on connectorized lines. Designers must respect the push-pull-only requirement and the VCCA <= VCCB rail-order constraint, applying proper power-sequencing so the low-voltage rail never exceeds the B-port rail during crank profiles.
Recommended
Recommended Products Summary
Engineering reference data for TXB0108PWR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TXB0108QPWRQ1 | TXS0108EPWR | NTS0108BQ/PW | TXB0104PWR |
|---|---|---|---|---|---|
| Package | TSSOP-20 (PW) | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-14 (PW) - different |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | NXP Semiconductors | Texas Instruments |
| Max Data Rate | 100 Mbps | 100 Mbps | ~60 Mbps | 100 Mbps | 100 Mbps (4 ch) |
| Open-Drain Support | No (push-pull only) | No | Yes | No | No |
| AEC-Q100 | No | Yes | No (Q1 variant exists) | No | No (Q1 variant exists) |
| ESD Protection (HBM) | +/-15 kV | +/-15 kV | +/-15 kV | [DATA_NEEDED] | +/-15 kV |
| Channels | 8 | 8 | 8 | 8 | 4 |
| A Port Range | 1.2V to 3.6V | 1.2V to 3.6V | 1.2V to 3.6V | 1.2V to 3.6V | 1.2V to 3.6V |
Key Differentiators
- 100 Mbps auto-direction translation (vs TXS0108EPWR)
- No direction pin needed (vs SN74LVC8T245QPWRQ1)
- Automotive drop-in upgrade path (vs TXB0108QPWRQ1)
Design Notes
The TXB0108 supports push-pull (totem-pole) CMOS drivers only. Its internal 4 kOhm series resistors cannot sink open-drain currents, so I2C and wired-OR buses will fail. Per TI E2E guidance, use the pin-compatible TXS0108E for open-drain or pull-up topologies, accepting a lower ~60 Mbps data rate. Also ensure VCCA <= VCCB at all times, including power sequencing, to avoid latch-up.
Total load capacitance per channel should stay below approximately 70 pF. The one-shot edge accelerators fight the internal 4 kOhm resistors, and heavy capacitive loads stretch rise times, reducing the effective data rate well below the 100 Mbps maximum. Keep traces short, avoid stubs, and for bus loads beyond 70 pF consider the direction-controlled SN74LVC8T245 family, which has real output drivers.
Place 0.1uF ceramic decoupling capacitors within 2-3 mm of both VCCA and VCCB pins with short returns to a solid ground plane. The one-shot transients draw fast current spikes during each edge acceleration. Unused channels should not float: tie unused A-side inputs to GND or VCCA through a pull resistor, since the weak internal bias can permit oscillation on open lines.
Compliance Information
RoHS compliant per TI product page. AEC-Q100 qualification available on the TXB0108QPWRQ1 variant.
