TXB0108PWR - 8-Bit Bidirectional Level Shifter 100Mbps | TI
MPN: TXB0108PWR ✓ Hoạt độngTXB0108PWR Tóm tắt
A voltage-level translator is a logic IC that enables communication between devices operating at different supply voltages, such as a 1.8V microcontroller and a 3.3V or 5V peripheral. It sits in the hierarchy of logic ICs under level shifters (translators), which are essential in multi-voltage digital systems alongside buffers and bus transceivers. The TXB0108PWR uses auto-direction sensing, eliminating the need for a direction control pin and reducing firmware complexity.
Key features include auto-direction sensing, +/-15-kV ESD protection (HBM), a 100 Mbps maximum data rate, and a VCC isolation feature: if either VCC input is at GND, all outputs enter the high-impedance state, enabling partial-power-down operation with Ioff support. The device operates from -40C to +85C.
Technically, the TXB0108 uses a one-shot architecture that accelerates low-to-high transitions to achieve 100 Mbps. It is designed for push-pull (totem-pole) CMOS drivers only; for open-drain buses such as I2C, TI recommends the TXS0108E. Output drive is intentionally weak (internal 4 kOhm series resistors), so heavy capacitive loads above ~70 pF reduce achievable speed.
Typical applications include 1.8V-to-3.3V microcontroller-to-sensor interfaces, SD card level shifting, UART/SPI signal translation, and FPGA configuration buses. The 100 Mbps capability suits high-speed SPI and UART links.
Design tip: ensure VCCA <= VCCB, drive all eight channels push-pull, and place 0.1uF decoupling capacitors close to both VCCA and VCCB pins with short traces for signal integrity.
Bộ thay thế dễ dàng lắp đặt cho TXB0108PWR — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với TXB0108PWR (cùng hình factor và footprint) — khác nhau ở Operating Temperature, Direction Control, Output Type, Translator Type, Package.
TXB0108QPWRQ1
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →TXB0108PWRG4
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TXS0108EQPWRQ1
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →NXB0108PW
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
TXB0108PWR Tỷ lệ tối đa & tính chất điện
| Bits per Channel | 8 |
| Kênh | 8 |
| Translator Type | Bidirectional voltage-level translator, auto-direction sensing |
| A Port Voltage Range | 1.2 V to 3.6 V |
| B Port Voltage Range | 1.65 V to 5.5 V |
| Max Data Rate | 100 Mbps |
| ESD Protection | +/-15 kV (HBM) |
| Kiểu đầu ra | Push-pull, 3-state |
| VCC Isolation | Yes - outputs high-impedance if either VCC at GND |
| Nhiệt độ hoạt động | -40C to +85C |
| Hộp | TSSOP-20 (PW) |
| Kiểu lắp đặt | Surface Mount |
| Internal Series Resistance | 4 kOhm |
| Latch-Up Performance | Exceeds 100 mA per JESD 78, Class II |
| Driver Type | Push-pull (totem-pole) CMOS only; not for open-drain buses |
| Trạng thái RoHS | Compliant |
Cấu hình chân TXB0108PWR
| Chân 1 | VCCA — A-port supply, 1.2V to 3.6V |
| Chân 2 | A1 — A-port data I/O 1 |
| Chân 3 | A2 — A-port data I/O 2 |
| Chân 4 | A3 — A-port data I/O 3 |
| Chân 5 | A4 — A-port data I/O 4 |
| Chân 6 | GND — Ground |
| Chân 7 | B4 — B-port data I/O 4 |
| Chân 8 | B3 — B-port data I/O 3 |
| Chân 9 | B2 — B-port data I/O 2 |
| Chân 10 | B1 — B-port data I/O 1 |
| Chân 11 | NC — No connect |
| Chân 12 | NC — No connect |
| Chân 13 | NC — No connect |
| Chân 14 | B5 — B-port data I/O 5 |
| Chân 15 | B6 — B-port data I/O 6 |
| Chân 16 | B7 — B-port data I/O 7 |
| Chân 17 | B8 — B-port data I/O 8 |
| Chân 18 | A8 — A-port data I/O 8 |
| Chân 19 | A7 — A-port data I/O 7 |
| Chân 20 | NC — No connect |
Ứng dụng tiêu biểu
TXB0108PWR phù hợp cho 6 Áp dụngs: MCU-to-Sensor Level Shifting (1.8V to 3.3V), SD Card Interface Level Translation, UART Signal Translation, FPGA Configuration and I/O Bank Translation, Mixed-Voltage Industrial Control Boards, Portable and Battery-Powered Devices.
MCU-to-Sensor Level Shifting (1.8V to 3.3V)
The TXB0108PWR fits 1.8V microcontroller-to-3.3V sensor interfaces because its A port accepts 1.2V-3.6V and its B port 1.65V-5.5V, matching common logic levels exactly. Auto-direction sensing means no firmware-managed DIR pin on point-to-point links such as SPI or sensor data lines. Place the device between the 1.8V MCU and 3.3V sensor rails with 0.1uF decoupling on both VCCA and VCCB; its 100 Mbps rating comfortably covers typical SPI clocks of 10-50 MHz, though keep trace lengths short due to the internal 4 kOhm series resistors.
Được đề xuất
SD Card Interface Level Translation
SD cards in SDIO mode traditionally use 2.7-3.6V signaling while newer low-voltage MCUs run at 1.8V; the TXB0108PWR bridges this with its 1.2V-3.6V A port and 1.65V-5.5V B port. Its 100 Mbps capability supports the 50 MHz default SDIO clock (parallel data across 8 channels covers CMD plus 4 data lines plus spares). Designers should keep SDIO traces matched and short since the one-shot edge accelerators lose speed above roughly 70 pF of trace and pin capacitance, and VCCA must not exceed VCCB.
Được đề xuất
UART Signal Translation
UART links between a 1.8V/2.5V processor and a 3.3V or 5V peripheral are a classic TXB0108PWR use case: each of the 8 channels is bidirectional with auto-direction sensing, so RX/TX pairs map directly without control logic. UART rates of 115.2 kbps to 4 Mbps are far below the 100 Mbps ceiling, leaving generous margin even with moderate load capacitance. Because both sides are push-pull CMOS, the TXB's 4 kOhm internal series resistors pose no issue; avoid adding pull-ups for this application and reserve TXS0108E for open-drain variants.
Được đề xuất
FPGA Configuration and I/O Bank Translation
FPGA banks operating at 1.8V frequently need to talk to 3.3V flash, configuration PROMs, or legacy peripherals; the TXB0108PWR's 8-bit width and VCC isolation make it a natural fit. If either rail powers down, outputs go high-impedance, enabling partial-power-down designs with Ioff support so floating buses do not back-power the FPGA. SPI configuration clocks of 10-50 MHz fall well within the 100 Mbps limit. Tie OE low during power-up sequencing to keep the bus tri-stated until both supplies stabilize.
Được đề xuất
Mixed-Voltage Industrial Control Boards
Industrial controllers often mix 5V legacy I/O with modern 1.8V/3.3V processors. The TXB0108PWR translates between these domains with +/-15-kV HBM ESD robustness, valuable in factory environments with handling and cable discharge events. Its -40C to +85C industrial temperature range and latch-up performance exceeding 100 mA per JESD 78 Class II suit harsh conditions. Designers should enforce VCCA <= VCCB in power sequencing and use the OE pin for clean power-up; the TSSOP-20 footprint enables compact, dense control-board layouts.
Được đề xuất
Portable and Battery-Powered Devices
Battery-powered products routinely combine a low-voltage (1.8V) low-power MCU with 3.3V displays, memory cards, and radios. The TXB0108PWR supports partial-power-down via its VCC isolation feature: when either rail collapses, all 8 outputs enter high-impedance, preventing leakage into the sleeping domain. Quiescent current is low enough for portable designs, and the small TSSOP-20 body fits compact layouts. Keep capacitive loading on each channel under ~70 pF to preserve signal edges, and drive channels push-pull CMOS for best speed.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho TXB0108PWR — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | TXB0108QPWRQ1 | TXB0108PWRG4 | TXS0108EQPWRQ1 | NXB0108PW |
|---|---|---|---|---|---|
| Package | TSSOP-20 (PW) | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same | TSSOP-20 (PW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | NXP Semiconductors |
| Bits / Channels | 8 | 8 | 8 | 8 | 8 |
| 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 |
| B Port Range | 1.65V to 5.5V | 1.65V to 5.5V | 1.65V to 5.5V | 1.65V to 5.5V | 1.65V to 5.5V |
Bảo phân biệt quan trọng
- Auto-direction sensing eliminates a DIR pin (vsSN74LVC8T245)
- 100 Mbps speed via one-shot edge accelerators (vsTXS0108EQPWRQ1)
- VCC isolation with Ioff support (vsNXB0108PW)
Ghi chú thiết kế
Place 0.1uF ceramic decoupling capacitors as close as possible to both VCCA (pin 1) and VCCB pins with short, low-inductance returns to GND. The one-shot edge-rate accelerators draw fast transient currents during transitions; inadequate decoupling causes ground bounce and false direction switching. Keep all eight channel traces short and matched-length for parallel buses like SDIO, since trace and pin capacitance above roughly 70 pF per channel degrades the achievable data rate due to the internal 4 kOhm series resistors.
The most common design error is using the TXB0108 on open-drain buses such as I2C. The auto-direction sensing and 4 kOhm series resistors produce contention with pull-up-based signaling; TI explicitly recommends the TXS0108E for open-drain applications. Also enforce VCCA <= VCCB at all times including power sequencing - tie OE low until both rails stabilize to keep outputs in high-impedance during startup, then release OE to enable translation.
Load each channel with a pure push-pull CMOS receiver and minimize capacitive loading. Avoid connecting multiple receivers in a multi-drop arrangement - the weak 4 kOhm internal drivers are designed for point-to-point links only. For longer buses or heavy loads, use the SN74LVC8T245 family instead, which offers strong output drive and a controlled direction pin. The +/-15-kV HBM ESD rating helps during assembly and handling but does not replace system-level TVS protection on external connectors.
Thông tin tuân thủ
RoHS compliant per TI product page; the PWR suffix indicates lead-free finish. Automotive AEC-Q100 variant is TXB0108QPWRQ1. Other compliance values not stated in provided data.
