VIPER22A-E STMicroelectronics, VIPER22A-E Datasheet - Page 8

• Manufacturer Part Number: VIPER22A-E
• Description: Fixed frequency off line converter
• Manufacturer: STMicroelectronics

Specifications of VIPER22A-E

• Constant Current Output: 350 mA, 700 mA, 1.05 A (selectable)
• Input Voltage Range: 90 to 264 VAC 50/60 Hz

Operations
4.2
4.3
8/21
Wide range of V
The V
design to achieve various behaviors. In
chosen to supply the device with two benefits:
●
●
Feedback pin principle of operation
A feedback pin controls the operation of the device. Unlike conventional PWM control
circuits which use a voltage input (the inverted input of an operational amplifier), the FB pin
is sensitive to current.
Figure 5.
As soon as the device starts switching, it immediately receives some energy from the
auxiliary winding. C5 can be therefore reduced and a small ceramic chip (100 nF) is
sufficient to insure the filtering function. The total start up time from the switch on of
input voltage to output voltage presence is dramatically decreased.
The output current characteristic can be maintained even with very low or zero output
voltage. Since the TSM101 is also supplied in forward mode, it keeps the current
regulation up whatever the output voltage is.The V
the input voltage, that is to say with a ratio of about 4 for a wide range application.
DD
pin voltage range extends from 9 V to 38 V. This feature offers a great flexibility in
Internal current control structure
Figure 5.
DD
voltage
Doc ID 12050 Rev 2
presents the internal current mode structure.
Figure 4 on page 7
VIPer22A-E, VIPer22ADIP-E, VIPer22AS-E
DD
a forward configuration has been
pin voltage may vary as much as