Pin settings

VIPER26

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Doc ID 17736 Rev 2

3

Pin settings

Figure 3.

Connection diagram (top view)

Note:

The copper area for heat dissipation has to be designed under the DRAIN pins.

Table 3.

Pin description

Pin n.

Name

Function

DIP-7 SO16

11-2

GND

Connected to the source of the internal power MOSFET and controller

ground reference.

-4

N.A.

Not available for user. It can be connected to GND (pins 1-2) or left not

connected.

25

VDD

Supply voltage of the control section. This pin provides the charging current

of the external capacitor.

36

LIM

This pin allows setting the drain current limitation. The limit can be reduced

by connecting an external resistor between this pin and GND. Pin left open if

default drain current limitation is used.

47

FB

Inverting input of the internal trans conductance error amplifier. Connecting

the converter output to this pin through a single resistor results in an output

Table 7). An external resistors divider is required for higher output voltages.

58

COMP

Output of the internal trans conductance error amplifier. The compensation

network have to be placed between this pin and GND to achieve stability and

good dynamic performance of the voltage control loop. The pin is used also

to directly control the PWM with an

(

Table 7).

7,8

13-16 DRAIN

High voltage drain pin. The built-in high voltage switched start-up bias

current is drawn from this pin too.

Pins connected to the metal frame to facilitate heat dissipation.