ST VIPER16 based 3W home appliance and meter power solution

The demand for small power supplies is growing, and the main markets for this type of SMPS are home appliances and meters. Even with rated voltages of 400 VAC and 415 VAC, these power supplies are not limited by the voltage range. The actual voltage level can reach 500 VAC (415 V + 20%).

Special requirements for meter power

1, very high voltage stability,

2, high anti-discharge ability,

3, reduce noise in the communication band

4, the peak power of data transmission!

The advantages of using ST Viper are

1, three switching frequency options to avoid noise in the communication band

2, extremely high avalanche rugged power MOSFET,

3, can provide a wide range of input Vac, embedded error amplifier, direct feedback from the output or primary adjustment,

4.Settable peak power timer

Special requirements for small home appliances are

1.Low standby power

2, high efficiency at light load

3.Small EMI input filter

4, ultra-wide input voltage

5, small size

The advantages of using ST Viper are

1, Frequency compensation can reduce EMI, thus realize small input filter

2.Meets the strictest energy-saving regulations

3.Zero power mode, can turn off and wake up IC through smart interface with MCU for touch buttons or remote control

4,800 V avalanche rugged power MOSFET to cover ultra-low wide range input Vac

5, reduced number of parts

6, Embedded error amplifier, direct feedback from output or primary regulation

7, reduced peak drain current during startup

8, wide power supply voltage range

The new STMicroelectronics ™ monolithic converter family is well suited for this range of input voltages, thanks to the 800 V avalanche rugged MOSFET integrated in the same power supply packaged with the control chip. This application note introduces a low-power SMPS with the following features: Using the VIPer16 fixed-frequency offline converter from STMicroelectronics as the main circuit of a buck topology. The VIPer16 device includes an 800 V rugged power switch, a PWM controller, programmable over-current, over-voltage, overload, and hysteretic thermal protection. Soft-start and safe auto-restart can be performed after any fault conditions are eliminated. Burst-mode operation with light loads coupled with the device's extremely low power consumption helps meet standby energy-saving regulations. The significant advantages of this new chip come from the switching frequency and the possibility of supplying the chip directly from the DC HV bus, so auxiliary supply is not mandatory. VIPer16 is suitable for flyback or buck topology, because it has internal self-powered circuit, so no auxiliary power is needed. STEVAL-ISA010V1 is a simple non-isolated auxiliary power supply based on VIPER16, suitable for input voltage range from 85 VAC to 500 VAC.

The VIPER16 device includes an 800 V rugged power switch, a PWM controller, programmable over-current, over-voltage, overload, hysteretic thermal protection, soft-start, and a feature that automatically restarts safely after eliminating any fault conditions. Burst-mode operation at light loads and very low device power consumption help meet standby energy-saving regulations. The significant advantages of this new chip come from the jitter of the switching frequency and the possibility of being supplied directly to the chip from DC high voltage, so there is no need to force the auxiliary power supply. VIPER16 is suitable for flyback or buck topology, and because it has internal self-powered circuit, no auxiliary power is needed.

Scene application diagram

Product entity diagram

Solution block diagram

Core technology advantages

 Robustness and reliability: thermal shutdown, soft start, OLP protection, automatic restart

Energy saving: Low standby power consumption, 96 mW at 230 VAC

 High integration: direct feedback, high-voltage startup

 Flexibility: scalable power, no auxiliary winding, no clamp design, no CM EMC filter

 Wide input voltage

 Streamlined parts, low cost

Solution specifications

 EMC: burst-IEC 61000-4-4-8 kV

 EMC: Surge-IEC 61000-4-5-2 kV

 RoHS compliant

 Isolation: Non-isolated -N is connected to output GND

 PCB type and size: FR4, single side 70μmdim .: 27 x 45 mm

 Input voltage Vin: 85-500 VAC (f: 45-66 Hz)

Output current: 150 mA (5 V and 12 V output) over the entire input voltage range

 Output voltage: V1 = 12 V ± 10%, V2 = 5 V ± 4%

 Short circuit protection

 EMI: conform to EN55022-B

 Standby: 96 mW at 230 VAC