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STMicroelectronics STEVAL-ISA121V1
- Part No.:
- STEVAL-ISA121V1
- Manufacturer:
- STMicroelectronics
- Package:
- Datasheet:
-
STEVAL-ISA121V1.pdf
- Description:
- EVAL BOARD FOR VIPER37
- Quantity:
- Payment:
- Shipping:
Inventory:2,082
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Product details
Overview
STEVAL-ISA121V1 from STMicroelectronics is a single-output 5 V / 3 A (15 W) demonstration board based on the VIPER37LE offline flyback controller-MOSFET IC, designed for auxiliary power supply in LCD/LED TVs and desktop computers during main PSU standby mode. It supports universal AC input (90–264 VAC), achieves <30 mW no-load consumption at 230 VAC, and delivers >75% average efficiency across load and line conditions.
For engineers reviewing the STEVAL-ISA121V1 datasheet, STEVAL-ISA121V1 application, STEVAL-ISA121V1 schematic, or STEVAL-ISA121V1 bill of materials, this board serves as a validated reference design for low-standby, EuP Lot 6–compliant auxiliary SMPS targeting USB port powering, remote control receivers, and always-on logic circuits in consumer electronics.
Technical Context
The board implements a fixed-frequency discontinuous conduction mode (DCM) flyback topology using the VIPER37LE's integrated 800 V avalanche-rugged MOSFET (RDS(on) ≤ 4.5 Ω) and PWM controller. Feedback is optocoupler-isolated via KB817A and regulated by TS431 shunt reference with precise 2.5 V reference voltage.
Protections include auto-restart overload, overvoltage, brownout, transformer saturation, shorted secondary rectifier detection, and hysteretic thermal shutdown - all implemented without external sensing components beyond standard passive elements and the VIPER37LE's internal monitoring circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 5 V ±0.15 V (line/load regulation maintained within ±1% from 0–3 A, 90–264 VAC) |
| Max Output Power | 15 W continuous (5 V @ 3 A), derated above 50°C ambient |
| Standby Consumption | <30 mW at 230 VAC, enabling compliance with EuP Lot 6 and ENERGY STAR 2.0 |
| Average Efficiency | >75% at full load (115/230 VAC), exceeding EPA 2.0 minimum threshold |
| Input Range | 90–264 VAC, 45–65 Hz - supports global mains without manual selection |
| EMC Compliance | EN 55022 Class B conducted & radiated emissions, verified per board layout and BOM |
| Safety Protections | Auto-restart OVP, OCP, brownout, thermal, transformer saturation, and shorted rectifier detection |
Availability
STEVAL-ISA121V1 is available at Aetrix Electronics and suitable for LCD TV auxiliary supplies, desktop PC standby power rails, and smart display remote-receiver power systems requiring stable component supply, pre-validated safety compliance, and low-noise 5 V output under light-load conditions.
Supply support for STEVAL-ISA121V1 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, designing and manufacturing microcontrollers, power ICs, analog chips, and MEMS sensors for industrial, automotive, and consumer applications.
This board belongs to ST's STEVAL (ST Evaluation) series - purpose-built reference designs that demonstrate application-specific implementation of ST's power, interface, and control ICs with fully documented schematics, layouts, and test data.
FAQ
What is the primary function of the STEVAL-ISA121V1 board?
The STEVAL-ISA121V1 is a complete, tested 5 V / 3 A auxiliary power supply reference design. Its primary function is to deliver ultra-low standby power (<30 mW) while maintaining tight output regulation - specifically for powering always-on subsystems like IR receivers, USB charging ports, and network controllers when the main system PSU is off or in standby mode.
Does the board support automatic restart after fault conditions?
Yes. All protection mechanisms - including overload, overvoltage, brownout, transformer saturation, shorted secondary rectifier, and thermal faults - operate in auto-restart mode. After fault removal, the VIPER37LE automatically resumes switching within 1–2 seconds without requiring manual reset or external intervention.
Can the output voltage be adjusted to 3.3 V or 12 V?
No. The board is fixed at 5 V output by its feedback resistor divider (R10/R11), optocoupler gain, and TS431 reference configuration. Modifying output voltage requires redesigning the feedback network, adjusting transformer turns ratio, and revalidating all protections and efficiency - not supported out-of-box.
Is the STEVAL-ISA121V1 RoHS compliant and certified for EMC?
Yes. The board is RoHS compliant per EU Directive 2011/65/EU and has been tested to meet EN 55022 Class B limits for conducted and radiated emissions. Full test reports and layout documentation are included in the official ST reference design package (Doc ID 024066).
STEVAL-ISA121V1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- VIPer™ plus
- Packaging:
- Box
- Product Status:
- Active
- Main Purpose:
- AC/DC, Primary Side
- Outputs and Type:
- 1 Non-Isolated Output
- Voltage - Output:
- 15 W
- Current - Output:
- 5V
- Voltage - Input:
- 3A
- Regulator Topology:
- 90 ~ 264 VAC
- Frequency - Switching:
- Flyback
- Contents:
- 115kHz
- Utilized IC / Part:
- Board(s)
- Power - Output:
- VIPer37
STEVAL-ISA121V1 FAQ
1.How can I place an order for STEVAL-ISA121V1 through Aetrix?
Please submit a Request for Quotation (RFQ) for STEVAL-ISA121V1 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 STEVAL-ISA121V1 reliable?
The price and inventory of STEVAL-ISA121V1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STEVAL-ISA121V1 is usually 5 days.
3.What payment methods are accepted for STEVAL-ISA121V1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STEVAL-ISA121V1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STEVAL-ISA121V1?
STEVAL-ISA121V1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STEVAL-ISA121V1 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 STEVAL-ISA121V1?
For technical support, including STEVAL-ISA121V1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STEVAL-ISA121V1 requirements.
6.How does Aetrix verify that STEVAL-ISA121V1 is sourced from the original manufacturer or authorized distributors?
All STEVAL-ISA121V1 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 STEVAL-ISA121V1 meets industry standards.
7.What is the process for return or replacement of STEVAL-ISA121V1?
All STEVAL-ISA121V1 units undergo pre-shipment inspection (PSI). If there is an issue with STEVAL-ISA121V1, 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 STEVAL-ISA121V1 part is unused and in its original packaging.
Return procedure for STEVAL-ISA121V1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STEVAL-ISA121V1 Tags
-
DFR0571
DFRobot
-
DFR0379
DFRobot
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DFR0205
DFRobot
-
1385
Adafruit Industries LLC
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COM-15208
SparkFun Electronics
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1944
Adafruit Industries LLC
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2465
Adafruit Industries LLC
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DC2468A
Analog Devices Inc.
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DC2841A
Analog Devices Inc.
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TPS552892EVM-111
Texas Instruments
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TPS55289EVM-093
Texas Instruments
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EPC9158
EPC
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