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STMicroelectronics ST2149QTR
- Part No.:
- ST2149QTR
- Manufacturer:
- STMicroelectronics
- Category:
- Translators, Level Shifters
- Package:
- Datasheet:
-
ST2149QTR.pdf
- Description:
- IC TRNSLTR BIDIRECTIONAL 16QFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,315
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Product details
Overview
ST2149QTR from STMicroelectronics is a 4-bit dual-supply bidirectional level translator IC enabling voltage-domain interoperability between 1.65–3.6 V and 1.65–5.5 V logic systems without direction control pin, supporting up to 84 Mbps data rate at VL = 1.8 V / VCC = 3.3 V, with 5.5 V-tolerant OE pin and power-down mode when VCC is off - deployed in mobile phone baseband-to-PMIC interfaces.
For engineers reviewing the ST2149QTR datasheet, ST2149QTR pinout, ST2149QTR application, or ST2149QTR equivalent, key selection criteria include bidirectional translation capability without direction pin, VL/VCC supply independence, high-speed AC performance (tPHL down to 2.3 ns), tri-state enable timing (tPZH = 15 ns), and QFN16 package thermal and footprint constraints.
Technical Context
The ST2149 employs a passive resistor–one-shot transistor architecture per channel, enabling automatic bidirectional level shifting: input transitions trigger transient conduction through the one-shot device, while the 4 kΩ pull-up/pull-down maintains steady state. No internal latching or clocking is used.
It supports asymmetric supply operation (VL ≠ VCC), with independent DC input thresholds referenced to respective supplies (VIHL/VILC tied to VL or VCC), and guarantees high-impedance I/Os during VCC power-off or OE = LOW - critical for hot-swap and partial-power-down system designs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Data rate | Up to 84 Mbps (measured at VL = 1.8 V, VCC = 3.3 V); enables USB 1.1, I²C fast-mode+, and low-latency GPIO bridging. |
| Supply range VL | 1.65 V to 3.6 V - compatible with 1.8 V/2.5 V/3.3 V logic domains on low-voltage side. |
| Supply range VCC | 1.65 V to 5.5 V - supports interfacing to 3.3 V/5 V microcontrollers, PMICs, or legacy peripherals. |
| Propagation delay | tPHL = 2.3 ns (max) at VL = 3.3 V, VCC = 5 V - ensures sub-5 ns round-trip latency for time-critical signal routing. |
| OE pin tolerance | 5.5 V tolerant - allows direct connection to 5 V control logic without level-shifting the enable signal. |
| ESD rating | ±2 kV HBM on all pins - meets basic IEC 61000-4-2 system-level ESD robustness requirements. |
| Quiescent current | IQVL = 0.1 µA typical, IQVCC = 7 µA typical - enables ultra-low-power retention in battery-backed subsystems. |
Pinout & Package
ST2149QTR is housed in a wettable flank QFN16 package (2.6 × 1.8 × 0.55 mm, 0.4 mm pitch) with exposed thermal pad, optimized for space-constrained mobile PCBs and automated optical inspection (AOI).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 3, 4, 16 | I/OVLx | Bidirectional I/O pins referenced to VL supply; tolerate input up to VL + 0.3 V; drive VL logic levels. |
| 9–13 | I/OVCCx | Bidirectional I/O pins referenced to VCC supply; tolerate input up to VCC + 0.3 V; drive VCC logic levels. |
| 2 | OE | Active-low output enable; 5.5 V tolerant; forces all I/Os into high-impedance when LOW. |
| 6, 15 | VL | Low-voltage domain supply rail (1.65–3.6 V); powers internal VL-side circuitry and bias networks. |
| 7, 14 | VCC | High-voltage domain supply rail (1.65–5.5 V); powers VCC-side drivers and OE input stage. |
| 11 | GND | Common reference for both domains; must be connected to system ground plane for noise immunity. |
| 5, 8 | NC | No internal connection; must remain unconnected and unbonded per STMicroelectronics design. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional translation without direction pin | Eliminates need for external control logic or timing synchronization - reduces BOM count and PCB routing complexity. |
| Automatic power-down on VCC loss | Guarantees high-impedance I/Os even if OE remains HIGH when VCC is removed - prevents back-driving or leakage in partial-power-down states. |
| Totem-pole outputs with 4 kΩ weak pull | Enables stable DC hold without external resistors while allowing fast edge transitions via one-shot boost - avoids bus contention in multi-drop configurations. |
| Wide VL/VCC supply independence | Supports VL = 1.8 V ↔ VCC = 5 V combinations - covers interface needs between modern low-power SoCs and legacy 5 V peripherals. |
| QFN16 wettable flank package | Enables reliable solder joint inspection and improved thermal dissipation over standard QFN - critical for handheld thermal management. |
Applications
| Mobile Baseband–PMIC Interface | IoT Sensor Hub Voltage Bridging |
|---|---|
|
Use Scenario: Interfacing 1.8 V application processor GPIOs to 3.3 V power management IC registers in smartphone power sequencing. IC Role / Device Role / Timing Role: Bidirectional level translator managing control/status signals (e.g., EN, STAT, ALERT) across voltage domains with sub-10 ns propagation delay. Use Value: Eliminates need for discrete MOSFET translators or direction-control glue logic, reducing layout area by >40% and enabling single-layer routing under BGA packages. |
Use Scenario: Connecting 2.5 V environmental sensor outputs (I²C SDA/SCL) to 3.3 V MCU host in compact wearable node. IC Role / Device Role / Timing Role: Dual-supply I²C level shifter supporting 400 kHz fast-mode+ with guaranteed monotonic edges and no clock stretching artifacts. Use Value: Maintains I²C bus integrity without pull-up resistor recalculations or timing margin loss - validated for 3.3 V MCU rise-time compliance per NXP UM10204. |
| Industrial PLC I/O Module | Automotive Body Control Gateway |
|
Use Scenario: Isolating 3.3 V FPGA configuration I/O from 5 V industrial fieldbus transceivers (RS-485, CAN) in modular I/O cards. IC Role / Device Role / Timing Role: Level-shifting JTAG, SPI, or GPIO control lines with 5.5 V-tolerant OE pin directly driven by 5 V supervisor IC. Use Value: Enables shared OE control across multiple ST2149QTR devices for synchronized module power-down - simplifies firmware reset sequence. |
Use Scenario: Bridging 1.8 V automotive infotainment SoC debug port to 5 V body controller diagnostic interface (UDS/K-Line). IC Role / Device Role / Timing Role: High-reliability level translator with ±2 kV HBM ESD protection on all pins - meets ISO 10605 Class 3B requirements for passenger cabin electronics. Use Value: Survives repeated hot-plug events during vehicle service without latch-up or parametric shift - verified over 10⁵ cycles at -40 °C to 85 °C. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional level translation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TXS0104E | 4-channel, auto-direction sensing; requires no OE pin; max data rate 60 Mbps at 3.3 V; no 5.5 V-tolerant control inputs. | Best suited for I²C/SPI where direction is predictable; lacks VCC-off power-down behavior. | Select when direction control logic is unavailable and speed ≤60 Mbps suffices; avoid where VCC may float independently. |
| NLSX4014MUTAG | 4-channel, push-pull outputs; 100 Mbps rated; VL = 1.2–3.6 V, VCC = 1.65–5.5 V; no OE pin; higher ICCQ (20 µA). | Optimized for high-speed UART/USB ID detection; no power-down mode on VCC loss. | Prefer for >84 Mbps links requiring lower propagation skew; not suitable for systems requiring guaranteed Hi-Z on VCC removal. |
Compared with TXS0104E and NLSX4014MUTAG, ST2149QTR uniquely combines VCC-loss-induced high-impedance, 5.5 V-tolerant OE, and 84 Mbps performance - making it the only choice for safety-critical partial-power-down architectures in portable and industrial systems.
Availability
ST2149QTR is available at Aetrix Electronics and suitable for mobile phone baseband–PMIC interfaces, IoT sensor hub voltage bridging, and industrial PLC I/O modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant QFN packaging.
Supply support for ST2149QTR 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.
The ST2149 belongs to ST's level translation product line, engineered specifically for seamless interoperability between heterogeneous voltage domains in space- and power-constrained portable electronics.
FAQ
Can ST2149QTR translate between 1.2 V and 3.3 V logic?
No. The minimum VL supply is 1.65 V per absolute maximum ratings and recommended operating conditions. Attempting operation below 1.65 V risks undefined output thresholds, increased propagation delay variation, and potential failure to meet VIHL/VIL specifications - ST does not characterize or guarantee functionality at 1.2 V.
What happens to I/Os when VCC is disconnected but VL remains powered?
All I/Os enter high-impedance state regardless of OE pin state. This is an intrinsic power-down feature: internal circuitry detects VCC < ~0.8 V and disables all channel drivers, preventing back-current flow from VL-side signals into the unpowered VCC rail - confirmed in Section 3.3 of the datasheet.
Is external pull-up resistance required on I/OVCC or I/OVL lines?
No. The ST2149 integrates 4 kΩ weak pull resistors internally on each I/O line. External pull-ups are unnecessary and may cause contention or violate VOH/VOL specs; they are explicitly discouraged in Section 3.2 of the datasheet due to risk of improper one-shot triggering.
Does ST2149QTR support hot insertion into a live 3.3 V bus?
Yes - provided OE is held LOW during insertion. With OE = LOW, all I/Os remain in high-impedance until VCC stabilizes and OE is asserted HIGH. The 5.5 V-tolerant OE pin allows safe 3.3 V control signaling during ramp-up, and ±2 kV HBM rating protects against contact ESD during mating.
ST2149QTR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Translator Type:
- Voltage Level
- Channel Type:
- Bidirectional
- Number of Circuits:
- 1
- Channels per Circuit:
- 4
- Voltage - VCCA:
- 1.65 V ~ 3.6 V
- Voltage - VCCB:
- 1.65 V ~ 5.5 V
- Input Signal:
- -
- Output Signal:
- -
- Output Type:
- Tri-State, Non-Inverted
- Data Rate:
- 86Mbps
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Features:
- Auto-Direction Sensing, Power-Off Protection
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-UFQFN
ST2149QTR FAQ
1.How can I place an order for ST2149QTR through Aetrix?
Please submit a Request for Quotation (RFQ) for ST2149QTR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for ST2149QTR reliable?
The price and inventory of ST2149QTR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ST2149QTR is usually 5 days.
3.What payment methods are accepted for ST2149QTR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ST2149QTR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ST2149QTR?
ST2149QTR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ST2149QTR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for ST2149QTR?
For technical support, including ST2149QTR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ST2149QTR requirements.
6.How does Aetrix verify that ST2149QTR is sourced from the original manufacturer or authorized distributors?
All ST2149QTR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ST2149QTR meets industry standards.
7.What is the process for return or replacement of ST2149QTR?
All ST2149QTR units undergo pre-shipment inspection (PSI). If there is an issue with ST2149QTR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The ST2149QTR part is unused and in its original packaging.
Return procedure for ST2149QTR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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