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STMicroelectronics TS3121IYCT
- Part No.:
- TS3121IYCT
- Manufacturer:
- STMicroelectronics
- Category:
- Comparators
- Package:
- 5-TSSOP, SC-70-5, SOT-353
- Datasheet:
-
TS3121IYCT.pdf
- Description:
- RAIL-TO-RAIL, OPEN-DRAIN COMPARA
- Quantity:
- Payment:
- Shipping:
Inventory:3,000
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Product details
Overview
TS3121IYCT from STMicroelectronics is a rail-to-rail input, open-drain single comparator with 60 ns propagation delay, 2 mV max offset voltage (A-grade), 70 μA typical supply current, and operation from 1.7 to 5.5 V. It features built-in hysteresis (1 mV), power-on reset capability (P-version), and AEC-Q100 qualification for automotive use in overcurrent protection circuits.
For engineers reviewing the TS3121IYCT datasheet, TS3121IYCT pinout, TS3121IYCT application, or TS3121IYCT equivalent, this device supports high-speed, low-power threshold detection in space-constrained industrial and automotive systems requiring guaranteed start-up time, extended temperature operation (–40 °C to +125 °C), and robust ESD tolerance (4 kV HBM).
Technical Context
The TS3121IYCT implements a precision comparator core with rail-to-rail input stage enabling full common-mode range (–0.2 V to VCC+ + 0.2 V) and open-drain output capable of sinking up to 140 mA at 5 V while tolerating output voltages exceeding VCC. Its internal hysteresis (1 mV) eliminates oscillation near threshold without external components.
It operates across 1.7–5.5 V supply and delivers stable performance over –40 °C to +125 °C, with input offset drift as low as 3 µV/°C and CMRR ≥55 dB. The device guarantees ≤15 µs start-up time and exhibits low input bias current (5–200 pA) and high PSRR (≥58 dB), making it suitable for battery-powered and noise-sensitive sensing nodes.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Propagation delay | 60 ns typ. - enables fast response in overcurrent fault detection and timing-critical window comparators. |
| Input offset voltage | 2 mV max @ 25 °C (A-grade) - ensures accurate threshold setting in precision voltage monitoring applications. |
| Supply current | 70 μA typ. - supports ultra-low-power operation in always-on battery-backed systems. |
| Supply voltage range | 1.7 to 5.5 V - compatible with single-cell Li-ion, 3.3 V logic, and 5 V legacy rails without level shifting. |
| Operating temperature | –40 °C to +125 °C - validated for under-hood automotive and industrial motor control environments. |
| ESD tolerance | 4 kV HBM - provides robust handling during PCB assembly and field deployment in noisy environments. |
| Output type | Open-drain - allows wired-OR configuration, flexible pull-up voltage selection (up to 6 V), and interface with mixed-voltage logic. |
Pinout & Package
TS3121IYCT is housed in a SC70-5 package (2.0 mm × 1.25 mm, 0.65 mm pitch), optimized for high-density PCB layouts in automotive and portable equipment.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OUT) | Open-drain output | Sinks current when IN+ > IN−; requires external pull-up; withstands voltages > VCC for level translation. |
| 2 (VCC−) | Negative supply | Ground reference terminal; supports true rail-to-rail input down to –0.2 V relative to this pin. |
| 3 (IN+) | Non-inverting input | Accepts input signals from –0.2 V to VCC+ + 0.2 V; low bias current (5 pA typ.) minimizes loading on high-Z sources. |
| 4 (IN−) | Inverting input | Same common-mode range as IN+; differential hysteresis (1 mV) suppresses noise-induced chatter. |
| 5 (VCC+) | Positive supply | Supplies internal circuitry; supports 1.7–5.5 V operation; thermal resistance 205 °C/W (SC70-5). |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail input stage | Enables direct sensing of signals near ground or supply rails without attenuation or clamping diodes. |
| Built-in 1 mV hysteresis | Eliminates need for external positive feedback resistors in noisy environments like motor drives or power tools. |
| AEC-Q100 qualified | Validated for automotive Grade 1 (–40 °C to +125 °C) including stress testing per JESD47, ensuring reliability in safety-critical ECUs. |
| Low 70 μA supply current | Reduces quiescent power in always-on fault monitors-e.g., <1.8 µW at 2.5 V-extending battery life in portable diagnostics. |
| Output pin voltage tolerance | Withstands up to 6 V at OUT pin independent of VCC, enabling direct interface with 5 V logic or higher-voltage bus monitoring. |
Applications
| Overcurrent Protection | Automotive Body Control Module |
|---|---|
|
Use Scenario: Real-time detection of excessive current in 12 V automotive power distribution networks using shunt resistor feedback. IC Role / Device Role / Timing Role: Comparator compares amplified shunt voltage against programmable threshold; open-drain output triggers MCU interrupt or latch circuit within 60 ns. Use Value: Enables sub-millisecond fault response with guaranteed start-up time and AEC-Q100 reliability for ISO 16750-compliant designs. |
Use Scenario: Window monitoring of battery voltage and sensor supply rails in door module ECUs operating across cold-crank (6.5 V) to load-dump (18 V) conditions. IC Role / Device Role / Timing Role: Dual-threshold detection (via external resistors) flags undervoltage/overvoltage events; rail-to-rail inputs track rails down to 1.7 V. Use Value: Eliminates external level shifters and reduces BOM count by supporting direct 3.3 V MCU interface with 4 kV HBM ESD robustness. |
| Industrial Motor Starter | Power Tool Battery Management |
|
Use Scenario: Monitoring phase current in BLDC motor drivers to initiate shutdown before IGBT thermal runaway occurs. IC Role / Device Role / Timing Role: High-speed comparator detects overcurrent spikes; open-drain output pulls gate driver enable low within 60 ns propagation delay. Use Value: Prevents destructive failure by reacting faster than typical microcontroller ADC sampling cycles (≥10 µs), leveraging guaranteed 15 µs start-up time. |
Use Scenario: Cell voltage balancing and pack-level overvoltage cutoff in cordless drill battery packs (18–21 V nominal, 25.2 V max). IC Role / Device Role / Timing Role: Compares scaled cell voltage against reference; low 70 μA ICC extends shelf-life of stored tools without compromising response speed. Use Value: Reduces PCB area via SC70-5 footprint and avoids external hysteresis components, lowering total solution cost by ~$0.12 per unit at volume. |
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); 30 ns propagation delay; 100 μA ICC. | Better suited for driving LEDs or logic directly; less flexible for mixed-voltage interfacing. | Select when board space permits larger SOT23-5 and push-pull drive simplifies layout. |
| TS3011IYCT | Higher speed (25 ns typ.); 120 μA ICC; same SC70-5 package; no built-in hysteresis. | Requires external hysteresis resistors; better for ultra-fast timing but increases component count. | Choose for sub-30 ns response where power budget allows +50 μA and design can accommodate external feedback. |
Compared with TS3121IYCT, TS3021ILT trades open-drain flexibility for simpler drive capability, while TS3011IYCT prioritizes speed over power efficiency and integrated hysteresis-making TS3121IYCT optimal for low-power, noise-immune, space-constrained automotive and industrial sensing.
Availability
TS3121IYCT is available at Aetrix Electronics and suitable for automotive body control modules, industrial motor starters, and power tool battery management systems requiring stable component supply across extended temperature and long product lifecycles.
Supply support for TS3121IYCT 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 such as automotive powertrain and industrial automation.
FAQ
What is the maximum output sink current for TS3121IYCT at 5 V supply?
At VCC = 5 V and T = 25 °C, TS3121IYCT guarantees a minimum sink current of 100 mA (typ. 140 mA) with VOL ≤ 45 mV at 1 mA load. Full datasheet specifications confirm 70 mA min. across –40 °C to +125 °C, enabling direct drive of small relays or optocouplers without buffering.
Does TS3121IYCT include built-in hysteresis, and how is it implemented?
Yes-TS3121IYCT integrates 1 mV of internal hysteresis, defined as the voltage difference between rising and falling input trip points. This is achieved via on-chip feedback and requires no external components, reducing design complexity and PCB area in noisy applications like motor current sensing.
Can TS3121IYCT operate from a 1.8 V supply, and what is its performance at that voltage?
Yes-TS3121IYCT is fully specified from 1.7 V to 5.5 V. At 1.8 V, it maintains 60 ns propagation delay (typ.), 78 μA supply current (max), and 36 mV VOL at 1 mA sink, with input common-mode range extending from –0.2 V to 2.0 V, supporting modern ultra-low-voltage IoT sensor nodes.
Is TS3121IYCT pin-compatible with other variants in the TS3121 family?
Yes-TS3121IYCT (A-grade), TS3121IYDT (standard grade), and TS3121PYCT (P-version with Power-on Reset) share identical SC70-5 pinout and footprint. Only functional differences (offset voltage, PoR) exist; no layout changes are required when upgrading between grades.
TS3121IYCT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- 5-TSSOP, SC-70-5, SOT-353
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- General Purpose
- Number of Elements:
- 1
- Output Type:
- Open-Drain, Rail-to-Rail
- Voltage - Supply, Single/Dual (±):
- 1.7V ~ 5V
- :
- 6mV @ 5V
- Voltage - Input Offset (Max):
- 50pA @ 5V
- Current - Input Bias (Max):
- 140mA @ 5V
- Current - Output (Typ):
- 125µA
- Current - Quiescent (Max):
- 70dB CMRR, 80dB PSRR
- CMRR, PSRR (Typ):
- 135ns
- Propagation Delay (Max):
- 1mV
- Hysteresis:
- -40°C ~ 125°C
- Operating Temperature:
- Automotive
- Grade:
- AEC-Q100
- Qualification:
- Surface Mount
- :
- SOT-323-5
TS3121IYCT FAQ
1.How can I place an order for TS3121IYCT through Aetrix?
Please submit a Request for Quotation (RFQ) for TS3121IYCT 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 TS3121IYCT reliable?
The price and inventory of TS3121IYCT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS3121IYCT is usually 5 days.
3.What payment methods are accepted for TS3121IYCT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS3121IYCT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS3121IYCT?
TS3121IYCT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS3121IYCT 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 TS3121IYCT?
For technical support, including TS3121IYCT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS3121IYCT requirements.
6.How does Aetrix verify that TS3121IYCT is sourced from the original manufacturer or authorized distributors?
All TS3121IYCT 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 TS3121IYCT meets industry standards.
7.What is the process for return or replacement of TS3121IYCT?
All TS3121IYCT units undergo pre-shipment inspection (PSI). If there is an issue with TS3121IYCT, 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 TS3121IYCT part is unused and in its original packaging.
Return procedure for TS3121IYCT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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