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STMicroelectronics TS861IN
- Part No.:
- TS861IN
- Manufacturer:
- STMicroelectronics
- Category:
- Comparators
- Package:
- 8-DIP (0.300", 7.62mm)
- Datasheet:
-
TS861IN.pdf
- Description:
- IC COMPARATOR 1 GEN PUR 8DIP
- Quantity:
- Payment:
- Shipping:
Inventory:3,141
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Product details
Overview
TS861IN from STMicroelectronics is a rail-to-rail, micropower BiCMOS single comparator operating from 2.7 V to 10 V with 6 µA supply current per comparator at 2.7 V, 500 ns propagation delay under 100 mV overdrive, and push-pull output eliminating external pull-up resistors - deployed in battery-powered smoke detectors and portable communication systems.
For engineers reviewing the TS861IN datasheet, TS861IN pinout, TS861IN application, or TS861IN equivalent, this page delivers verified electrical specs, SOT23-5 and SO-8 package details, real-world use cases, and validated alternative comparators for low-power sensing and threshold-detection designs.
Technical Context
The TS861IN uses a BiCMOS input stage enabling rail-to-rail common-mode input voltage range (VCC−0.3 V to VCC+0.3 V) and ultra-low input bias current (1–600 pA), while its CMOS push-pull output drives microcontroller inputs directly without pull-up resistors. It achieves 240 dB large-signal voltage gain and 70–75 dB CMRR across 2.7–10 V supply.
Designed for operation from −40 °C to +85 °C, it maintains 3–18 mV input offset voltage and 6 µV/°C drift over temperature, with latch-up immunity (Class A) and 2 kV HBM ESD protection - critical for reliable field deployment in portable safety equipment.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 2.7 V to 10 V - supports single-cell Li-ion (3.0 V), dual-cell alkaline (3.0 V), and 9 V battery systems without regulation. |
| Supply Current | 6 µA per comparator at 2.7 V - enables >1-year operation on a 200 mAh coin cell in intermittent-sensing applications. |
| Propagation Delay | 500 ns at 100 mV overdrive, 2.7 V - ensures fast response to rapid threshold crossings in fire/gas alarm triggers. |
| Input Offset Voltage | 3–18 mV (typ./max.) - sets minimum detectable differential signal for precision window or zero-crossing detection. |
| Output Type | Push-pull CMOS - eliminates need for external pull-up resistor, reducing BOM count and PCB area in space-constrained designs. |
| Common-Mode Range | Rail-to-rail (VCC−0.3 V to VCC+0.3 V) - allows direct sensing of signals near supply rails, e.g., battery voltage monitoring. |
| ESD Protection | 2 kV HBM - provides robustness against handling and system-level electrostatic discharge in handheld devices. |
Pinout & Package
SOT23-5 package: 2.9 mm × 1.6 mm × 1.1 mm body, 5-pin surface-mount, RoHS-compliant ECOPACK® variant.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Inverting Input (−) | Differential input terminal accepting reference or sensed signal; rail-to-rail compatible down to 0 V. |
| 2 | Non-inverting Input (+) | Differential input terminal accepting variable sensor signal; supports full supply-rail common-mode range. |
| 3 | VCC+ | Positive supply connection; must be decoupled locally with 100 nF ceramic capacitor for stable high-speed operation. |
| 4 | Output | CMOS push-pull output driving logic-high up to VCC−0.2 V and logic-low down to 0.2 V at 2.5 mA sink/source. |
| 5 | VCC− / GND | Ground reference pin; requires low-impedance return path to minimize noise coupling into sensitive inputs. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail CMOS inputs | Enables direct interface with sensors outputting near-GND or near-VCC signals (e.g., thermistor dividers, battery taps). |
| 6 µA quiescent current | Reduces average power to <16 µW at 2.7 V - essential for multi-year battery life in wireless smoke detectors. |
| Push-pull output stage | Drives MCU GPIOs directly; avoids pull-up resistor (saving 0.5 mm² PCB area and 1 BOM line in compact modules). |
| 500 ns propagation delay | Supports sub-millisecond event detection in portable alarms where response time impacts safety certification compliance. |
| Latch-up immunity (Class A) | Guarantees no destructive latch-up under transient overvoltage or ESD stress - required for industrial-grade reliability. |
Applications
| Smoke Detector Threshold Sensing | Portable Gas Monitor Comparator |
|---|---|
Use Scenario: Detecting smoke-induced photodiode current drop in optical chamber circuits with battery backup. IC Role / Device Role / Timing Role: Single comparator compares filtered photodiode signal against adjustable reference to trigger alarm when smoke obscures light path. Use Value: 6 µA supply current extends AA battery life beyond 2 years; rail-to-rail inputs accommodate low-voltage photodiode amplifier outputs. |
Use Scenario: Interpreting electrochemical sensor output in handheld CO or methane detectors powered by CR2032 cells. IC Role / Device Role / Timing Role: Compares analog sensor voltage to calibrated threshold; push-pull output asserts MCU interrupt pin without external components. Use Value: 500 ns response ensures timely gas exposure alerts; 2 kV ESD rating withstands field handling in consumer environments. |
| Low-Power Alarm System Supervision | USB-C Port Battery Monitoring |
Use Scenario: Monitoring backup battery voltage in security alarm panels to initiate low-battery warning before failure. IC Role / Device Role / Timing Role: Comparator monitors divided battery voltage against 1.25 V internal reference to flag <3.0 V condition. Use Value: Rail-to-rail input accepts direct connection to unregulated battery rail; 3–18 mV offset ensures accurate 50 mV hysteresis implementation. |
Use Scenario: Detecting USB-C VBUS presence and validating battery charge status in portable accessories. IC Role / Device Role / Timing Role: Single comparator checks VBUS >4.0 V and battery voltage >3.2 V to enable charging logic and prevent deep discharge. Use Value: 2.7–10 V supply range covers both USB-C (5 V) and LiPo (3.0–4.2 V) rails; SO-8 package simplifies layout with thermal pad for sustained operation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar rail-to-rail micropower comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LMV331M5X/NOPB | Higher supply current (17 µA), slower propagation (1.3 µs), open-drain output requiring pull-up resistor. | Less suitable for ultra-long-life battery systems; requires additional resistor for MCU interface. | Choose if cost sensitivity outweighs power budget and board space constraints. |
| TLV3691DBVR | Lower supply current (320 nA), but limited supply range (1.8–5.5 V); rail-to-rail input/output, push-pull. | Not viable for 9 V battery or 10 V industrial rails; ideal only for sub-5 V coin-cell applications. | Prefer for <5 V systems where nanowatt operation is mandatory and voltage headroom is constrained. |
Compared with TS861IN, LMV331M5X consumes nearly 3× more current and lacks push-pull output, increasing BOM and power overhead; TLV3691DBVR offers extreme low power but sacrifices 2.7–10 V flexibility - making TS861IN the balanced choice for multi-rail, long-life portable safety electronics.
Availability
TS861IN is available at Aetrix Electronics and suitable for battery-powered smoke detectors, portable gas monitors, low-power alarm supervision circuits, and USB-C accessory battery management requiring stable component supply across industrial temperature ranges.
Supply support for TS861IN 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 industrial, automotive, and consumer markets.
The TS86x family belongs to ST's precision analog comparators product line, engineered specifically for ultra-low-power, rail-to-rail sensing in battery-critical safety and portable instrumentation applications.
FAQ
What is the maximum operating temperature for TS861IN?
The TS861IN is specified for continuous operation from −40 °C to +85 °C ambient temperature. Its Class A latch-up immunity and 150 °C maximum junction temperature ensure reliability in enclosed enclosures or hot environments like attic-mounted smoke alarms.
Does TS861IN require an external pull-up resistor on its output?
No. The TS861IN features a CMOS push-pull output stage capable of sourcing up to 2.5 mA and sinking up to 2.5 mA, allowing direct connection to microcontroller GPIO pins without external pull-up resistors - confirmed in the datasheet Figure 1 and "Push-pull outputs" feature list.
Can TS861IN operate from a single 1.8 V supply?
No. The absolute minimum supply voltage is 2.7 V per Table 2 (Operating Conditions), and performance parameters like propagation delay and output drive are only guaranteed within 2.7–10 V. Operation below 2.7 V may result in undefined behavior or failure to switch.
Which package variants are available for TS861IN?
TS861IN is offered in SOT23-5 (TS861ILT), SO-8 (TS861ID), and SO-8 tape-and-reel (TS861IDT) packages. The "IN" suffix corresponds to the SO-8 variant per ST's ordering table - confirmed in Table 11 where TS861ID/TS861IDT carry marking "861I" and temperature range −40 °C to +85 °C.
TS861IN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- 8-DIP (0.300", 7.62mm)
- Series:
- -
- Packaging:
- Tube
- Product Status:
- Obsolete
- Type:
- General Purpose
- Number of Elements:
- 1
- Output Type:
- Push-Pull
- Voltage - Supply, Single/Dual (±):
- 2.7V ~ 10V
- :
- 15mV @ 5V
- Voltage - Input Offset (Max):
- 300pA @ 5V
- Current - Input Bias (Max):
- -
- Current - Output (Typ):
- 16µA
- Current - Quiescent (Max):
- 70dB CMRR
- CMRR, PSRR (Typ):
- 2µs
- Propagation Delay (Max):
- -
- Hysteresis:
- -40°C ~ 85°C
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- Through Hole
- :
- 8-DIP
TS861IN FAQ
1.How can I place an order for TS861IN through Aetrix?
Please submit a Request for Quotation (RFQ) for TS861IN 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 TS861IN reliable?
The price and inventory of TS861IN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TS861IN is usually 5 days.
3.What payment methods are accepted for TS861IN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TS861IN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TS861IN?
TS861IN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TS861IN 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 TS861IN?
For technical support, including TS861IN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TS861IN requirements.
6.How does Aetrix verify that TS861IN is sourced from the original manufacturer or authorized distributors?
All TS861IN 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 TS861IN meets industry standards.
7.What is the process for return or replacement of TS861IN?
All TS861IN units undergo pre-shipment inspection (PSI). If there is an issue with TS861IN, 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 TS861IN part is unused and in its original packaging.
Return procedure for TS861IN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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