Datasheet

VIPER37 Pin settings
Doc ID 022218 Rev 1 5/35
3 Pin settings
Figure 3. Connection diagram (top view)
Note: The copper area for heat dissipation must be designed under the DRAIN pins.
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Table 3. Pin description
Pin n. Name Function
1 GND This pin represents the device ground and the source of the power section.
2VDD
Supply voltage of the control section. This pin also provides the charging current
of the external capacitor during startup time.
3CONT
Control pin. The following functions can be selected:
1. current limit set point adjustment. The internal set default value of the cycle-by-
cycle current limit can be reduced by connecting to ground an external resistor.
2. output voltage monitoring. A voltage exceeding the V
OVP
threshold (see
Ta b l e 8 ) shuts the IC down reducing the device consumption. This function is
stropped and digitally filtered for high noise immunity.
4FB
Control input for duty cycle control. Internal current generator provides bias
current for loop regulation. A voltage below the threshold V
FBbm
activates the
burst mode operation. A level close to the threshold V
FBlin
means that we are
approaching the cycle-by-cycle overcurrent set point.
5BR
Brownout protection input with hysteresis. A voltage below the threshold V
BRth
shuts down (not latched) the device and lowers the power consumption. Device
operation restarts as the voltage exceeds the threshold V
BRth
+ V
BRhyst
.
It can be connected to ground when not used.
6...10 DRAIN
High voltage drain pin. The built-in high voltage switched startup bias current is
drawn from this pin too.
Pins connected to the metal frame to facilitate heat dissipation.