STEVAL-ISA004V1 STMicroelectronics, STEVAL-ISA004V1 Datasheet - Page 11
![EVAL BOARD DUAL OUTPUT VIPER22A](/photos/9/13/91315/steval-isa004v1_sml.jpg)
STEVAL-ISA004V1
Manufacturer Part Number
STEVAL-ISA004V1
Description
EVAL BOARD DUAL OUTPUT VIPER22A
Manufacturer
STMicroelectronics
Series
VIPER™r
Type
MOSFET & Power Driverr
Datasheets
1.VIPER22ADIP-E.pdf
(21 pages)
2.STEVAL-ISA004V1.pdf
(4 pages)
3.STEVAL-ISA004V1.pdf
(4 pages)
Specifications of STEVAL-ISA004V1
Mfg Application Notes
VIPer22A Dual Output - AppNote AN1736
Design Resources
STEVAL-ISA004V1 Gerber Files STEVAL-ISA004V1 Schematic STEVAL-ISA004V1 Bill of Materials
Main Purpose
AC/DC, Primary Side
Outputs And Type
2, Isolated
Power - Output
10W
Voltage - Output
5V, 12V
Current - Output
1A, 420mA
Voltage - Input
90 ~ 264VAC
Regulator Topology
Flyback
Frequency - Switching
60kHz
Board Type
Fully Populated
Utilized Ic / Part
VIPer22A
Architecture
Analog
Applications
Power
Input Voltage
3.3 V
Product
Power Management Modules
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
VN808CM
Other names
497-5864
VIPer22A-E, VIPer22ADIP-E, VIPer22AS-E
4.4
Startup sequence
Figure 7.
This device includes a high voltage start up current source connected on the drain of the
device. As soon as a voltage is applied on the input of the converter, this start up current
source is activated as long as V
current source is switched OFF and the device begins to operate by turning on and off its
main power MOSFET. As the FB pin does not receive any current from the optocoupler, the
device operates at full current capacity and the output voltage rises until reaching the
regulation point where the secondary loop begins to send a current in the optocoupler. At
this point, the converter enters a regulated operation where the FB pin receives the amount
of current needed to deliver the right power on secondary side.
This sequence is shown in
consumes some energy from the V
continuous supply. If the value of this capacitor is too low, the start up phase is terminated
before receiving any energy from the auxiliary winding and the converter never starts up.
This is illustrated also in the same figure in dashed lines.
Startup sequence
Figure 7
Doc ID 12050 Rev 2
DD
DD
. Note that during the real starting phase t
is lower than V
capacitor, waiting for the auxiliary winding to provide a
DDon
. When reaching V
DDon
ss
, the start up
, the device
Operations
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