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STMicroelectronics TSM1012AIDT
- Part No.:
- TSM1012AIDT
- Manufacturer:
- STMicroelectronics
- Category:
- Voltage Reference
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
TSM1012AIDT.pdf
- Description:
- IC VREF SERIES 0.5% 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,400
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Product details
Overview
TSM1012AIDT from STMicroelectronics is a dual-loop SMPS controller IC for secondary-side voltage and current regulation in flyback adapters and battery chargers. It integrates a 1.25 V ±0.5% precision voltage reference, two transconductance op-amps with ORed sink outputs, operates from 4.5 V to 28 V supply, consumes only 100–180 µA, and delivers up to 10 mA sink output current for optocoupler drive.
For engineers reviewing the TSM1012AIDT datasheet, TSM1012AIDT pinout, TSM1012AIDT application, or TSM1012AIDT equivalent, this device supports precise CV/CC control in compact, low-component-count AC/DC power supplies - especially where high mains rejection (65–100 dB), easy compensation, and thermal stability across –40 °C to +105 °C are required.
Technical Context
The TSM1012AIDT implements two independent transconductance amplifiers sharing a common open-collector output stage, enabling hardware ORing of voltage and current control loops. Its internal 1.25 V reference feeds both amplifier inputs via external resistor networks to set CV threshold (via R1/R2 divider) and CC threshold (via R4/R5/Vref network).
Each amplifier features fully accessible negative input and output pins for external compensation (e.g., 2.2 nF + 22 kΩ RC network), and exhibits 70–85 dB common-mode rejection, 65–100 dB supply voltage rejection, and <2 mV input offset voltage (typ. 0.5 mV for A-grade) over temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Voltage reference | 1.25 V ±0.5% at 25 °C; enables accurate CV/CC setpoints without external reference |
| Total supply current | 100–180 µA at VCC = 18 V; allows operation from weak auxiliary windings |
| Supply voltage range | 4.5 V to 28 V; accommodates wide-range auxiliary supplies with integrated 28 V Zener clamp |
| Input offset voltage | 0.5 mV max (TSM1012A); ensures tight current limit accuracy under varying load/temperature |
| Sink output current | 6–10 mA at OUT pin; directly drives standard optocouplers (e.g., PC817, LTV-817) without buffer |
| Common-mode rejection | 70–85 dB; maintains regulation integrity despite ground noise in secondary-side feedback paths |
| Operating temperature | –40 °C to +105 °C; qualified for industrial and automotive-grade adapter/charger environments |
Pinout & Package
Package: SO-8 (Small Outline, 150 mil width), RoHS-compliant ECOPACK® variant, surface-mountable with standard reflow profile.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VRef (Pin 1) | Analog output | Stable 1.25 V reference source; feeds both CV and CC sense networks |
| CC− (Pin 2) | Analog input | Inverting input of current-control op-amp; connected to low-side of Rsense |
| CC+ (Pin 3) | Analog input | Non-inverting input of current-control op-amp; tied to Vsense divider midpoint |
| CV− (Pin 4) | Analog input | Inverting input of voltage-control op-amp; connected to output voltage divider bottom |
| CV+ (Pin 5) | Analog input | Non-inverting input of voltage-control op-amp; tied to VRef via R1/R2 network |
| GND (Pin 6) | Power supply | 0 V reference for all analog signals; must be low-impedance local ground |
| OUT (Pin 7) | Analog output | Open-collector sink output shared by both op-amps; drives optocoupler LED cathode |
| VCC (Pin 8) | Power supply | Main supply input (4.5–28 V); includes internal Zener clamp at 28 V |
Key Features
| Feature | Design Value |
|---|---|
| Dual transconductance op-amps with ORed output | Enables automatic priority-based CV/CC regulation without external logic or diodes |
| Low 100–180 µA quiescent current | Reduces auxiliary winding burden and improves no-load efficiency in energy-efficient adapters |
| Integrated 1.25 V ±0.5% voltage reference | Eliminates need for external reference IC, reducing BOM count and layout area |
| Full external compensation access | Allows stable loop tuning for diverse transformer designs and optocoupler delays |
| High 65–100 dB supply voltage rejection | Maintains regulation accuracy despite ripple on auxiliary VCC derived from rectified mains |
Applications
| Smartphone Wall Adapter | Laptop AC Adapter |
|---|---|
|
Use Scenario: 5 V / 3 A USB-C PD adapter with constant-voltage and constant-current charging profiles. IC Role / Device Role / Timing Role: Secondary-side CV/CC controller regulating output via optocoupler feedback to primary PWM IC. Use Value: Enables ±1% output voltage and ±3% current limit accuracy across line/load/temperature while minimizing external components. |
Use Scenario: 20 V / 4.5 A laptop charger requiring tight regulation during battery pre-charge and fast-charge phases. IC Role / Device Role / Timing Role: Dual-loop feedback controller managing transition between CV and CC modes without software intervention. Use Value: Delivers seamless mode switching and stable regulation under dynamic load steps, supported by 105 °C operating range. |
| Power Tool Battery Charger | Medical Portable Device Charger |
|
Use Scenario: 24 V / 2 A lithium-ion charger for cordless power tools with thermal foldback protection. IC Role / Device Role / Timing Role: Precision current limiter and voltage supervisor interfacing with isolated secondary sensing circuitry. Use Value: Achieves <±2% current limit tolerance using only two matched resistors and internal VRef, improving charge consistency. |
Use Scenario: Compact 12 V / 1 A medical-grade charger for portable diagnostic equipment requiring low leakage and high reliability. IC Role / Device Role / Timing Role: Isolated feedback controller ensuring compliance with IEC 60601-1 creepage/clearance and safety isolation requirements. Use Value: Supports reinforced isolation via optocoupler while maintaining <180 µA supply current to reduce heat in sealed enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar CV/CC controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431BILP (Texas Instruments) | Single-reference shunt regulator; no integrated current-sense amplifier or dual-loop architecture | Requires external op-amp and reference for CC function; higher component count and layout complexity | Choose when only voltage regulation is needed or cost sensitivity outweighs integration benefits |
| KA431AZTA (ON Semiconductor) | Fixed 2.5 V reference; lacks transconductance amplifiers, VRef output, and dedicated CC pins | Cannot implement true independent CC loop without additional ICs; limited to basic CV-only topologies | Use only in legacy CV-only designs where upgrade path to dual-loop control is not required |
Compared with TL431BILP and KA431AZTA, the TSM1012AIDT provides native dual-loop control in one SO-8 package, eliminating discrete op-amps and reference ICs - reducing bill-of-materials, PCB area, and design validation effort for modern CV/CC adapters and chargers.
Availability
TSM1012AIDT is available at Aetrix Electronics and suitable for smartphone wall adapters, laptop AC adapters, and medical portable device chargers requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.
Supply support for TSM1012AIDT 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 silicon solutions for automotive, industrial, and power management applications.
The TSM1012 series belongs to ST's dedicated AC/DC secondary-side controller product line, engineered specifically for high-accuracy, low-power CV/CC regulation in isolated flyback converters used in consumer and industrial power adapters.
FAQ
What is the maximum sink current capability of the TSM1012AIDT OUT pin?
The OUT pin delivers a minimum sink current of 6 mA and a typical value of 10 mA when pulled to (VCC − 0.6 V), sufficient to drive standard optocouplers like PC817 without external buffering. This rating holds across the full –40 °C to +105 °C operating range and is validated per Table 5 in the official datasheet (DocID10124 Rev 2).
Can the TSM1012AIDT operate with a 3.3 V auxiliary supply?
No - the absolute minimum VCC is 4.5 V per Table 4 (Operating Conditions). A 3.3 V supply falls below specification and will prevent proper biasing of internal amplifiers and reference circuitry. Designers must ensure auxiliary winding delivers ≥4.5 V, or add a low-dropout boost stage before VCC.
How does the TSM1012AIDT achieve ORing between voltage and current control loops?
Both operational amplifiers share a single open-collector output stage (Pin 7). When either amplifier detects an overvoltage or overcurrent condition, its output sinks current, pulling the optocoupler LED cathode low - resulting in immediate primary-side PWM duty reduction. No external diodes or logic are needed.
Is external compensation mandatory for stable operation?
Yes - both op-amps require external compensation components (e.g., 2.2 nF capacitor + 22 kΩ resistor in series) connected between OUT and CC− or CV−, as shown in Figure 6 of the datasheet. Omitting compensation risks oscillation due to phase margin loss in the optocoupler-coupled feedback loop.
TSM1012AIDT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Reference Type:
- Series
- Output Type:
- Fixed
- Voltage - Output (Min/Fixed):
- 1.25V
- Voltage - Output (Max):
- -
- Current - Output:
- 2.5 mA
- Tolerance:
- ±0.5%
- Temperature Coefficient:
- -
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- 4.5V ~ 28V
- Current - Supply:
- 50mA
- Current - Cathode:
- -
- Operating Temperature:
- -40°C ~ 105°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
TSM1012AIDT FAQ
1.How can I place an order for TSM1012AIDT through Aetrix?
Please submit a Request for Quotation (RFQ) for TSM1012AIDT 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 TSM1012AIDT reliable?
The price and inventory of TSM1012AIDT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TSM1012AIDT is usually 5 days.
3.What payment methods are accepted for TSM1012AIDT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TSM1012AIDT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TSM1012AIDT?
TSM1012AIDT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TSM1012AIDT 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 TSM1012AIDT?
For technical support, including TSM1012AIDT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TSM1012AIDT requirements.
6.How does Aetrix verify that TSM1012AIDT is sourced from the original manufacturer or authorized distributors?
All TSM1012AIDT 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 TSM1012AIDT meets industry standards.
7.What is the process for return or replacement of TSM1012AIDT?
All TSM1012AIDT units undergo pre-shipment inspection (PSI). If there is an issue with TSM1012AIDT, 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 TSM1012AIDT part is unused and in its original packaging.
Return procedure for TSM1012AIDT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TSM1012AIDT Tags
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TL431AIDBZR
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TL431BQDBZR
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AN431AN-ATRG1
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LM4040CYM3-2.5-TR
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LM4040CYM3-4.1-TR
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LM4040EIM3-2.5/NOPB
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AZ431LBNTR-G1
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LM4040D20IDBZR
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LM4041DIM3-ADJ/NOPB
Texas Instruments
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LM4040DIM3X-2.5/NOPB
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LM4040DIM3-2.5/NOPB
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AZ431LANTR-G1
Diodes Incorporated
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