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STMicroelectronics TS3121AILT
- Part No.:
- TS3121AILT
- Manufacturer:
- STMicroelectronics
- Category:
- Comparators
- Package:
- -
- Datasheet:
-
TS3121AILT.pdf
- Description:
- RAIL-TO-RAIL, OPEN-DRAIN COMPARA
- Quantity:
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Inventory:3,000
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Product details
Overview
TS3121AILT from STMicroelectronics is a rail-to-rail input, open-drain single comparator qualified to AEC-Q100 Grade 1 (−40 °C to +125 °C), featuring 2 mV max input offset voltage at 25 °C, 70 μA typical supply current, 60 ns propagation delay (high-to-low, 100 mV overdrive), and operation from 1.7 V to 5.5 V supply. It serves as a precision voltage threshold detector in automotive overcurrent protection circuits.
For engineers reviewing the TS3121AILT datasheet, TS3121AILT pinout, TS3121AILT application, or TS3121AILT equivalent, this page delivers verified electrical specs, package mapping to SC70-5, functional safety documentation support, and validated alternatives for industrial and automotive sensor interface designs.
Technical Context
The TS3121AILT implements a high-speed CMOS comparator core with built-in hysteresis (1 mV), rail-to-rail input stage enabling full-supply-range sensing, and an open-drain output capable of sinking up to 140 mA while tolerating voltages exceeding VCC. Its internal architecture ensures guaranteed start-up within 15 µs after VCC exceeds 1.5 V.
Designed for harsh environments, it integrates ESD protection (4 kV HBM), operates across −40 °C to +125 °C, and achieves 70 dB CMRR and 80 dB SVR at 5 V supply - enabling stable performance in noisy power tool motor control and battery management systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 1.7 V to 5.5 V - supports direct connection to Li-ion, 3.3 V logic, and 5 V microcontroller I/O rails without level-shifting. |
| Input Offset Voltage | ≤ 2 mV at 25 °C (A-grade) - enables accurate detection of small differential signals (e.g., shunt-based current sensing down to ~10 mV). |
| Propagation Delay | 60 ns (tPHL, 100 mV overdrive, CL = 15 pF) - provides fast response for overcurrent fault shutdown in motor drivers. |
| Supply Current | 70 μA typical - allows continuous monitoring in always-on automotive subsystems with minimal battery drain. |
| Input Common-Mode Range | Rail-to-rail (−0.2 V to VCC+ + 0.2 V) - permits direct sensing of signals referenced to ground or VCC in single-supply systems. |
| Output Type | Open-drain - enables wired-OR configuration, flexible pull-up to higher voltage (e.g., 12 V), and safe interfacing with mixed-voltage logic. |
| ESD Tolerance | 4 kV HBM - meets automotive board-level robustness requirements without external protection diodes. |
Pinout & Package
TS3121AILT is housed in a 5-pin SC70-5 package (2.0 mm × 1.25 mm, 0.65 mm pitch), optimized for space-constrained automotive and industrial PCBs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OUT) | Open-drain output | Sinks current when IN+ > IN−; requires external pull-up; withstands voltages > VCC for mixed-rail interfacing. |
| 2 (VCC−) | Negative supply terminal | Ground reference for dual-supply operation; tied to GND in single-supply configurations. |
| 3 (IN+) | Non-inverting input | Accepts rail-to-rail analog input; used for threshold comparison against IN− in standard configurations. |
| 4 (IN−) | Inverting input | Accepts rail-to-rail analog input; commonly connected to sensed signal (e.g., shunt voltage) in overcurrent detection. |
| 5 (VCC+) | Positive supply terminal | Supplies internal circuitry; supports 1.7–5.5 V range; decoupling capacitor required near pin for stability. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q100 Grade 1 qualification | Validated for automotive powertrain and body electronics per stress test requirements (−40 °C to +125 °C). |
| Built-in 1 mV hysteresis | Eliminates oscillation on slow-moving or noisy input signals without external feedback components. |
| Guaranteed 15 µs start-up time | Ensures deterministic output state within defined window after power ramp, critical for fail-safe system initialization. |
| Rail-to-rail input with 70 dB CMRR | Accurately compares signals across full supply range while rejecting common-mode noise from shared ground paths. |
| Output pin withstands > VCC | Enables direct connection to 12 V bus or higher-voltage logic via external pull-up, simplifying level translation. |
Applications
| Automotive Overcurrent Protection | Industrial Motor Control |
|---|---|
|
Use Scenario: Monitoring shunt voltage in 12 V battery-fed DC motor drivers to detect stall or short-circuit faults. IC Role / Device Role / Timing Role: Precision voltage comparator triggering immediate shutdown via MCU interrupt or hardware latch. Use Value: 60 ns propagation delay enables sub-100 µs fault response, preventing MOSFET thermal runaway under overload. |
Use Scenario: Detecting phase current imbalance in 3-phase inverter gate driver feedback loops. IC Role / Device Role / Timing Role: High-speed comparator comparing sensed current against reference to initiate PWM blanking or fault flag assertion. Use Value: Rail-to-rail input and 2 mV offset enable accurate 50 mV shunt detection at 3.3 V logic supply, reducing BOM cost vs. instrumentation amplifiers. |
| Power Tool Battery Management | Automotive Body Controller Sensing |
|
Use Scenario: Real-time cell voltage monitoring in cordless drill battery packs during charge/discharge cycles. IC Role / Device Role / Timing Role: Low-power comparator detecting overvoltage/undervoltage thresholds to disable charging or cut load. Use Value: 70 μA supply current extends standby runtime; extended temperature range ensures reliability in hot tool housings. |
Use Scenario: Window comparator implementation for door lock actuator position feedback using potentiometer wiper voltage. IC Role / Device Role / Timing Role: Dual-threshold detection (via two TS3121AILT units) confirming mechanical end-stop position before motor deactivation. Use Value: AEC-Q100 qualification and 4 kV HBM ESD rating ensure robustness against automotive harness-induced transients. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar single comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TS3021ILT | Push-pull output (no external pull-up needed); 35 ns tPHL; 100 μA ICC - higher speed but no VCC-overvoltage tolerance. | Preferred where logic-level compatibility with 3.3 V MCU GPIO is required and mixed-voltage interfacing is unnecessary. | Select TS3021ILT when faster response and simplified output loading outweigh need for open-drain flexibility. |
| TS880IYLT | Lower ICC (35 μA typ.); same SC70-5 package; 100 ns tPHL; 3 mV VIO - lower power but slower and less precise. | Suitable for non-critical wake-up or status monitoring where microamp-level quiescent current dominates design priority. | Choose TS880IYLT only when ultra-low power is mandatory and 60 ns timing or 2 mV offset are not required. |
Compared with TS3121AILT, TS3021ILT trades open-drain versatility for speed and push-pull simplicity, while TS880IYLT sacrifices performance for ultra-low ICC - making TS3121AILT the optimal balance for AEC-Q100-compliant, precision, high-reliability threshold detection.
Availability
TS3121AILT is available at Aetrix Electronics and suitable for automotive overcurrent protection, industrial motor control, and power tool battery management requiring stable component supply across extended temperature and lifecycle demands.
Supply support for TS3121AILT 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 specializing in automotive, industrial, and power management solutions, with broad portfolio certification to AEC-Q100 and ISO 26262.
The TS3121 series belongs to ST's precision analog comparators product line, engineered specifically for high-reliability automotive and industrial sensing applications demanding low offset, fast response, and extended temperature operation.
FAQ
What is the maximum sink current capability of TS3121AILT at 125 °C?
At +125 °C and VCC = 5 V, TS3121AILT guarantees a minimum sink current of 45 mA (typ. 70 mA) with VOL ≤ 50 mV at 1 mA load. This is sufficient to directly drive optocoupler LEDs or low-power logic inputs in high-temperature automotive zones without external buffering.
Does TS3121AILT require external hysteresis for stable operation?
No. TS3121AILT integrates 1 mV of internal hysteresis, eliminating the need for external positive feedback resistors. This built-in feature prevents chatter on slowly varying or noisy inputs - confirmed by characterization data across −40 °C to +125 °C and all supply voltages (1.8 V to 5.5 V).
Can TS3121AILT operate with a single 1.8 V supply?
Yes. TS3121AILT is fully specified down to 1.7 V supply, including rail-to-rail input operation, 78 μA typical ICC, and 160 ns tPHL (100 mV overdrive) at 1.8 V. Input common-mode range extends to −0.2 V, supporting ground-referenced sensing in ultra-low-voltage systems.
Is functional safety documentation available for TS3121AILT?
Yes. STMicroelectronics provides functional safety documentation (including FMEDA reports and safety manuals) for TS3121AILT to support ISO 26262 ASIL-B system-level development. These documents are accessible through ST's official automotive support portal upon NDA registration.
TS3121AILT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- -
- Series:
- *
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- -
- Number of Elements:
- -
- Output Type:
- -
- Voltage - Supply, Single/Dual (±):
- -
- :
- -
- Voltage - Input Offset (Max):
- -
- Current - Input Bias (Max):
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- Current - Output (Typ):
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- Current - Quiescent (Max):
- -
- CMRR, PSRR (Typ):
- -
- Propagation Delay (Max):
- -
- Hysteresis:
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- Operating Temperature:
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- Grade:
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- Qualification:
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TS3121AILT FAQ
1.How can I place an order for TS3121AILT through Aetrix?
Please submit a Request for Quotation (RFQ) for TS3121AILT 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 TS3121AILT reliable?
The price and inventory of TS3121AILT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS3121AILT is usually 5 days.
3.What payment methods are accepted for TS3121AILT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS3121AILT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS3121AILT?
TS3121AILT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS3121AILT 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 TS3121AILT?
For technical support, including TS3121AILT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS3121AILT requirements.
6.How does Aetrix verify that TS3121AILT is sourced from the original manufacturer or authorized distributors?
All TS3121AILT 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 TS3121AILT meets industry standards.
7.What is the process for return or replacement of TS3121AILT?
All TS3121AILT units undergo pre-shipment inspection (PSI). If there is an issue with TS3121AILT, 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 TS3121AILT part is unused and in its original packaging.
Return procedure for TS3121AILT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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