Pin connections and function
VIPer22A-E, VIPer22ADIP-E, VIPer22AS-E
3
Pin connections and function
Figure 2.
Pin connection
1
2
3
4
8
7
6
5
1
2
3
4
8
7
6
5
DRAIN
DRAIN
DRAIN
DRAIN
SOURCE
SOURCE
FB
DRAIN
DRAIN
DRAIN
DRAIN
SOURCE
SOURCE
FB
VDD
VDD
SO-8
DIP-8
Figure 3.
Current and voltage conventions
IDD
ID
VDD
DRAIN
IFB
FB
CONTROL
VDD
VD
SOURCE
VFB
VIPer22A
Table 10. Pin function
Pin Name
Pin function
Power supply of the control circuits. Also provides a charging current during start up
thanks to a high voltage current source connected to the drain. For this purpose, an
hysteresis comparator monitors the VDD voltage and provides two thresholds:
VDD
- VDDon: Voltage value (typically 14.5 V) at which the device starts switching and turns
off the start up current source.
- VDDoff: Voltage value (typically 8 V) at which the device stops switching and turns on
the start up current source.
SOURCE Power MOSFET source and circuit ground reference.
Power MOSFET drain. Also used by the internal high voltage current source during
start up phase for charging the external VDD capacitor.
DRAIN
Feedback input. The useful voltage range extends from 0 V to 1 V, and defines the
FB
peak drain MOSFET current. The current limitation, which corresponds to the
maximum drain current, is obtained for a FB pin shorted to the SOURCE pin.
6/21
Doc ID 12050 Rev 2
STMICROELECTRONICS [ ST ]
