LSF0101 - 1-Bit Auto-Bidirectional Level Translator | Texas Instruments
MPN: LSF0101 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.28 | $0.28 |
| 10 | $0.25 | $2.50 |
| 100 | $0.2 | $20.00 |
| 500 | $0.17 | $85.00 |
| 1,000 | $0.14 | $140.00 |
Drop-in alternatives for LSF0101 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LSF0101GX
✅ Drop-In📋 Reference alternative (not in catalog)
LSF0101 Maximum Ratings & Electrical Characteristics
| Channels | 1 |
| Function | Auto-bidirectional multi-voltage level translator |
| Applications Supported | Open-drain and push-pull |
| Max Up-Translation Data Rate | 100 MHz |
| Down-Translation Data Rate | >= 100 MHz |
| Load Condition | <= 30 pF capacitive load |
| I/O Tolerance | 5 V tolerant I/O pins (TTL compatible) |
| Direction Pin | Not required (auto direction) |
| Package | 6-X2SON (1x0.8 mm) |
| Mounting Type | Surface Mount |
| Supply Voltage Range (VREF_A / VREF_B) | [DATA_NEEDED: VREF operating range] |
| Operating Temperature | [DATA_NEEDED: operating temperature range] |
| Propagation Delay | [DATA_NEEDED: propagation delay] |
| RoHS Status | [DATA_NEEDED: RoHS status] |
| MSL Level | [DATA_NEEDED: MSL level] |
LSF0101 Pin Configuration
| Pin 1 | VREF_A — Reference voltage, side A (lower voltage domain) |
| Pin 2 | GND — Ground |
| Pin 3 | A — Channel A I/O (side A) |
| Pin 4 | EN — Enable / bias input (high = translation active) |
| Pin 5 | B — Channel B I/O (side B) |
| Pin 6 | VREF_B — Reference voltage, side B (higher voltage domain) |
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
LSF0101 is suitable for 6 applications: I2C Bus Level Shifting, PMBus Power System Management, Industrial Control Systems, Mobile and Wearable Devices, Automotive Body and Comfort Electronics, Test and Measurement Instrumentation.
I2C Bus Level Shifting
The LSF0101 is purpose-built for open-drain two-wire buses like I2C, where SDA changes direction asynchronously. Its auto-bidirectional pass-gate architecture handles this without a DIR pin, unlike buffered translators such as SN74LVC1T45. With support for 5 V tolerant I/O, it bridges a 1.8 V MCU to a 3.3 V or 5 V sensor transparently. Place the device close to the MCU side, size the reference-side bias resistor (typically 200 kohm per TI guidance) and pull-ups so rise times meet I2C standard-mode or fast-mode timing at your bus capacitance.
Recommended
PMBus Power System Management
PMBus controllers often run at 3.3 V while power regulators and hot-swap controllers use other domains. TI product documentation explicitly lists PMBus among the buses the LSF family supports without a DIR pin. The 100 MHz capability provides ample margin over the 400 kHz-class PMBus clock, so propagation delay is negligible. Use one LSF0101 per bus line, or the LSF0102/LSF0108 for multi-line buses, and verify pull-up values so open-drain rise times satisfy the PMBus timing specification at the deployed bus length and capacitance.
Recommended
Industrial Control Systems
Industrial PLCs and factory automation nodes frequently mix 1.8 V/2.5 V/3.3 V logic domains. The LSF0101's 5 V tolerant I/O and TTL compatibility allow legacy 5 V devices to interface with modern low-voltage MCUs. Its small 1x0.8 mm X2SON footprint fits dense IO modules. The auto-bidirectional architecture suits both polled sensor buses and push-pull control lines. In noisy industrial environments, keep traces short, add local decoupling on both voltage references, and consider TVS protection such as TPD4S012 on externally accessible lines.
Recommended
Mobile and Wearable Devices
Wearables and mobile accessories need level translation between a 1.8 V application processor and 3.3 V peripherals such as sensors or codecs in extremely constrained board space. The LSF0101's 1 x 0.8 mm X2SON package minimizes footprint, and its passive pass-gate design draws minimal quiescent power, important for battery-operated products. Because there is no direction control, the host does not spend GPIO overhead. Route the translated line directly with short stubs; at <= 30 pF load the 100 MHz capability comfortably covers I2C fast-mode-plus and SPI rates below 50 Mbps.
Recommended
Automotive Body and Comfort Electronics
Automotive modules mix 3.3 V microcontroller IO with 5 V sensor and actuator interfaces. TI's automotive-qualified LSF0102-Q1 and related LSF variants extend this translation family to AEC-Q environments, indicating the architecture's suitability. For single-line needs, the LSF0101 architecture provides the same 100 MHz, auto-bidirectional behavior for LIN-adjacent control lines, sensor serial interfaces, and local I2C buses. Confirm qualification requirements; use the Q1 variants where AEC-Q100 compliance is mandated, and add series resistors plus TVS on harness-connected lines.
Recommended
Test and Measurement Instrumentation
Bench instruments and probes frequently need to interface logic analyzers or host controllers operating at different voltages than the device under test. The LSF0101's >= 100 MHz down-translation at 30 pF supports fast capture and stimulus lines, while its passive architecture adds minimal edge distortion compared to buffered translators. For push-pull signals it works directly; for open-drain protocols it auto-detects direction. Verify probe loading stays below the 30 pF guideline, and place the translator at the instrument connector to limit stub reflections.
Recommended
Recommended Products Summary
Engineering reference data for LSF0101 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LSF0101GX | LSF0102-Q1 | TXS0102-Q1 |
|---|---|---|---|---|
| Brand | Texas Instruments | Nexperia | Texas Instruments | Texas Instruments |
| Package | 6-X2SON (1x0.8 mm) | XSON-6 (near-identical) | VSSOP-8 - different | VSSOP-8 - different |
| Channels | 1 | 1 | 2 | 2 |
| Architecture | Pass-gate, auto-bidirectional, no DIR pin | Pass-gate, auto-bidirectional, no DIR pin | Pass-gate, auto-bidirectional | Buffered, auto-direction |
| Max Data Rate | 100 MHz up / >= 100 MHz down @ 30 pF | 100 MHz up / >= 100 MHz down @ 30 pF | 100 MHz class (LSF family) | 24 Mbps (much lower) |
| I/O Tolerance | 5 V tolerant (TTL compatible) | 5 V tolerant | 5 V tolerant | 5 V tolerant |
| I2C / Open-Drain Support | Yes (native, no DIR pin) | Yes (native) | Yes (native) | Yes (auto-direction) |
| Automotive Grade | No (standard grade) | No | Yes (Q1) | Yes (Q1) |
Key Differentiators
- Auto-bidirectional without DIR pin (vs SN74LVC1T45DCKR)
- 100 MHz class speed (vs TXS0102-Q1)
- Ultra-small 1x0.8 mm footprint (vs LSF0102-Q1)
Design Notes
The 6-X2SON (1 x 0.8 mm) footprint has 0.4 mm-class pitch and an exposed pad per TI package guidelines. Use 4-mil or finer traces, solder-mask-defined pads, and inspect with X-ray or AOI due to low standoff. Place the LSF0101 within a few millimeters of the bus connector or host side to minimize stub length, keeping total load at or below the 30 pF condition tied to the 100 MHz specification.
LSF translation quality depends on the reference-side bias network: VREF_B must be the higher of the two domain voltages, and the EN pin is biased from the low side reference through a resistor (TI LSF app guidance uses roughly 200 kohm). Decouple both VREF pins with 100 nF ceramic capacitors placed within 2 mm. An undersized or missing bias resistor raises the effective switch resistance and degrades rise time on open-drain buses.
On I2C/SMBus lines, rise time is set by pull-up resistance against total bus capacitance, not by the translator speed. Calculate pull-ups per RC rise-time budget: for fast-mode 300 ns rise at 100 pF, pull-ups around 2 to 3 kohm are typical. The LSF0101 switch adds series resistance, so include its on-resistance in the calculation and re-verify at maximum expected capacitance.
Compliance Information
Compliance data not present in provided web results; verify on TI.com quality pages. Automotive grade is available in the LSF0102-Q1 family variant.
