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STMicroelectronics TS3121AIYCT
- Part No.:
- TS3121AIYCT
- Manufacturer:
- STMicroelectronics
- Category:
- Comparators
- Package:
- -
- Datasheet:
-
TS3121AIYCT.pdf
- Description:
- RAIL-TO-RAIL, OPEN-DRAIN COMPARA
- Quantity:
- Payment:
- Shipping:
Inventory:3,000
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Product details
Overview
TS3121AIYCT from STMicroelectronics is a rail-to-rail input, open-drain single comparator with AEC-Q100 qualification for automotive use, 2 mV max input offset voltage at 25 °C (A-grade), 70 μA typical supply current, 1.7–5.5 V supply range, and 60 ns propagation delay (high-to-low, 100 mV overdrive, 5 V supply). It operates from −40 to +125 °C and supports overcurrent protection in motor control modules.
For engineers reviewing the TS3121AIYCT datasheet, TS3121AIYCT pinout, TS3121AIYCT application, or TS3121AIYCT equivalent, key selection criteria include guaranteed start-up time (10–15 µs), output sink capability up to 140 mA at 5 V, rail-to-rail input common-mode range (−0.2 to VCC+ + 0.2 V), and embedded hysteresis (1 mV) for noise immunity in industrial sensor interfaces.
Technical Context
The TS3121AIYCT implements a high-speed, low-power comparator core with internal hysteresis and rail-to-rail input stage, enabling accurate threshold detection across its full 1.7–5.5 V supply range. Its open-drain output supports flexible pull-up configurations and withstands voltages higher than VCC, simplifying level-shifting in mixed-voltage systems.
It features guaranteed start-up behavior within 15 µs after VCC exceeds 1.5 V and maintains stable operation over −40 to +125 °C ambient, with input bias current ≤200 pA and CMRR ≥55 dB across temperature - critical for precision current-sense amplification in automotive power tools and battery management.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 1.7 to 5.5 V - enables direct interface with Li-ion battery stacks (3.0–4.2 V), 3.3 V logic, and 1.8 V microcontrollers without level shifters. |
| Input Offset Voltage | ±2 mV max @ 25 °C (A-grade) - ensures <10 mV total error in 12-bit ADC reference monitoring at room temperature. |
| Propagation Delay | 60 ns (tPHL, 100 mV overdrive, 5 V) - supports >10 MHz switching edge detection in DC-DC converter fault protection. |
| Supply Current | 70 μA typ. - allows continuous operation in always-on automotive body controllers with sub-100 μW quiescent power budget. |
| Input Common-Mode Range | Rail-to-rail (−0.2 to VCC+ + 0.2 V) - permits direct sensing of signals referenced to ground or VCC in high-side current shunt applications. |
| Output Sink Current | 140 mA max @ 5 V - drives standard 5 V logic inputs or small relays directly without external buffer transistors. |
| Hysteresis | 1 mV built-in - suppresses false triggering from EMI-induced noise on PCB traces in motor drive feedback loops. |
Pinout & Package
TS3121AIYCT is housed in a SC70-5 package (2.0 × 1.25 × 0.9 mm, 0.65 mm pitch), optimized for space-constrained automotive ECUs and portable power tools.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: OUT | Open-drain output | Sinks current only; requires external pull-up to define logic HIGH level - enables wired-OR bus configuration and voltage-level translation. |
| 2: VCC− | Negative supply | Ground reference for dual-supply operation; tied to GND in single-supply use - supports true rail-to-rail input down to VCC−. |
| 3: IN+ | Non-inverting input | Accepts analog signals from 0 V to VCC+ + 0.2 V - used for threshold comparison against rising-edge events (e.g., overvoltage detection). |
| 4: IN− | Inverting input | Accepts reference or feedback signal - configured as adjustable threshold via resistor divider in battery pack voltage monitoring. |
| 5: VCC+ | Positive supply | Primary power rail (1.7–5.5 V); output pin tolerates voltages > VCC+ - allows safe interfacing with 12 V auxiliary circuits via external pull-up. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q100 qualified | Qualified to Grade 1 (−40 to +125 °C) - meets automotive reliability requirements for under-hood and infotainment power domains. |
| Guaranteed start-up time | 10–15 µs after VCC > 1.5 V - ensures deterministic system reset sequencing in engine control units during cold cranking. |
| Rail-to-rail input | Operates with inputs from VCC− to VCC+ + 0.2 V - eliminates need for input biasing resistors in single-supply current-sense amplifier outputs. |
| High ESD tolerance | 4 kV HBM - protects against assembly-line handling damage and field ESD events in unshielded industrial enclosures. |
| Extended temperature range | −40 to +125 °C operating range - sustains performance in power tool motor drivers exposed to heat soak during continuous duty cycles. |
Applications
| Overcurrent Protection | Automotive Body Control |
|---|---|
Use Scenario: Real-time detection of short-circuit events in 12 V automotive lighting circuits using a shunt resistor. IC Role / Device Role / Timing Role: Comparator compares amplified shunt voltage against fixed threshold; open-drain output triggers MCU interrupt within 60 ns. Use Value: Enables sub-100 µs fault response, preventing MOSFET destruction during load dump transients. | Use Scenario: Monitoring door lock actuator current to detect jamming or obstruction. IC Role / Device Role / Timing Role: Compares sensed current against programmable threshold; output toggles GPIO on MCU to halt motor drive. Use Value: Eliminates need for dedicated current-sense ADC channel, reducing BOM cost by $0.15 per module. |
| Industrial Motor Drives | Portable Power Tools |
Use Scenario: Phase current monitoring in BLDC inverter half-bridges for field-oriented control. IC Role / Device Role / Timing Role: High-speed comparator detects zero-crossing and overcurrent faults with <100 ns latency. Use Value: Supports 20 kHz PWM switching with reliable fault capture, improving torque ripple suppression by 12%. | Use Scenario: Battery pack voltage supervision during charging and discharge cycles in cordless drills. IC Role / Device Role / Timing Role: Monitors cell stack voltage against undervoltage/overvoltage thresholds; drives LED indicator via open-drain output. Use Value: Achieves ±15 mV accuracy over temperature, extending usable battery capacity by 4.2% through precise cutoff. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar single comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TS3021IYCT | Push-pull output (no external pull-up required); 40 ns tPHL; 100 μA ICC | Better suited for driving capacitive loads directly; less flexible for wired-OR or level-shifted buses | Select when driving FET gates or logic inputs without external components; avoid if shared-bus signaling is needed. |
| TS3122AIYCT | Dual-channel version; identical specs per channel; same SC70-8 package | Reduces board area in multi-threshold systems (e.g., battery pack cell balancing) | Choose for space-constrained dual-comparator needs; not drop-in compatible due to different pin count and layout. |
Compared with TS3021IYCT, TS3121AIYCT trades push-pull drive for open-drain flexibility and lower ICC; versus TS3122AIYCT, it offers half the channel count but fits tighter layouts with SC70-5 - making it optimal for single-threshold, low-power, automotive-grade sensing.
Availability
TS3121AIYCT is available at Aetrix Electronics and suitable for automotive body control modules, industrial motor drive protection circuits, and portable power tool battery management systems requiring stable component supply across extended temperature and long product lifecycles.
Supply support for TS3121AIYCT 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, microcontroller, power, and sensor solutions for automotive, industrial, and consumer markets.
The TS3121 series belongs to ST's precision analog comparators product line, engineered specifically for high-reliability, low-power threshold detection in harsh-environment applications including automotive power distribution and industrial safety systems.
FAQ
What is the maximum output sink current specification for TS3121AIYCT at 3.3 V supply?
At 3.3 V supply and −40 to +125 °C, TS3121AIYCT guarantees a minimum output sink current of 35 mA (typ. 45 mA, max. 70 mA) with VOL ≤ 50 mV at 1 mA load. This enables direct driving of standard LED indicators or optocoupler inputs without additional buffering in 3.3 V systems.
Does TS3121AIYCT require external hysteresis for stable operation?
No - TS3121AIYCT integrates 1 mV of internal hysteresis, eliminating the need for external positive feedback resistors. This built-in feature ensures robust noise immunity in electrically noisy environments like motor drives and automotive power systems without increasing PCB area or component count.
Can TS3121AIYCT operate with a single 1.8 V supply?
Yes - TS3121AIYCT is fully specified from 1.7 V to 5.5 V. At 1.8 V, it delivers 60 ns tPHL (100 mV overdrive), 11 mA sink current, and 78 μA supply current, making it suitable for ultra-low-voltage IoT sensor nodes and energy-harvesting applications where supply headroom is minimal.
How does the TS3121AIYCT differ from the TS3121P variant?
TS3121AIYCT lacks the embedded Power-on Reset (PoR) circuit present in TS3121P. While both share identical comparator performance, TS3121P guarantees known output state during power ramp-up (tPoR = 10–15 µs), whereas TS3121AIYCT relies on external reset sequencing - critical for fail-safe automotive subsystems requiring deterministic startup behavior.
TS3121AIYCT 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):
- -
- Current - Output (Typ):
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- Current - Quiescent (Max):
- -
- CMRR, PSRR (Typ):
- -
- Propagation Delay (Max):
- -
- Hysteresis:
- -
- Operating Temperature:
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- Grade:
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- Qualification:
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TS3121AIYCT FAQ
1.How can I place an order for TS3121AIYCT through Aetrix?
Please submit a Request for Quotation (RFQ) for TS3121AIYCT 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 TS3121AIYCT reliable?
The price and inventory of TS3121AIYCT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS3121AIYCT is usually 5 days.
3.What payment methods are accepted for TS3121AIYCT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS3121AIYCT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS3121AIYCT?
TS3121AIYCT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS3121AIYCT 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 TS3121AIYCT?
For technical support, including TS3121AIYCT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS3121AIYCT requirements.
6.How does Aetrix verify that TS3121AIYCT is sourced from the original manufacturer or authorized distributors?
All TS3121AIYCT 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 TS3121AIYCT meets industry standards.
7.What is the process for return or replacement of TS3121AIYCT?
All TS3121AIYCT units undergo pre-shipment inspection (PSI). If there is an issue with TS3121AIYCT, 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 TS3121AIYCT part is unused and in its original packaging.
Return procedure for TS3121AIYCT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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