STEVAL-ISA021V1 STMicroelectronics, STEVAL-ISA021V1 Datasheet - Page 12

• Manufacturer Part Number: STEVAL-ISA021V1
• Description: BOARD REF VIPER22A SGL OUTPUT
• Manufacturer: STMicroelectronics
• Series: VIPER™r

Specifications of STEVAL-ISA021V1

• Design Resources: STEVAL-ISA021V1 Gerber Files STEVAL-ISA021V1 Schematic STEVAL-ISA021V1 Bill of Material
• Main Purpose: AC/DC, Primary Side
• Outputs And Type: 1, Isolated
• Power - Output: 10W
• Voltage - Output: 12V
• Current - Output: 840mA
• Voltage - Input: 90 ~ 264VAC
• Regulator Topology: Flyback
• Frequency - Switching: 60kHz
• Board Type: Fully Populated
• Utilized Ic / Part: VIPer22A
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Other names: 497-5219

Circuit operation
1.8
12/17
Figure 10. Burst mode
Short circuit
The VIPer has pulse-by-pulse current limit. When the current ramps up to the current limit,
the pulse is terminated. This is manifested by reducing the output voltage as the current is
increased. The voltage decreases until it falls below the undervoltage shutdown threshold of
9 V, (pin4). During a short circuit the VIPer turns on and off. When the V
starting voltage, the current is limited by the pulse-by-pulse current limit. The voltage falls to
the undervoltage shutdown point and the cycle repeats itself at a 16% duty cycle. This
reduces the RMS current going through the circuit as seen in
Figure 11. Operation during a short
Figure
11.
dd
reaches the
AN2544