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L6590A

PIN FUNCTIONS

THERMAL DATA

(*) Value depending on PCB copper area and thickness

.

ABSOLUTE MAXIMUM RATINGS

N°

Pin

Description

1

DRAIN

Drain connection of the internal power MOSFET. The internal high voltage start-up generator

sinks current from this pin.

2

N.C.

Not internally connected. Provision for clearance on the PCB.

3

Vcc

Supply pin of the IC. An electrolytic capacitor is connected between this pin and ground. The

internal start-up generator charges the capacitor until the voltage reaches the start-up threshold.

The PWM is stopped if the voltage at the pin exceeds a certain value.

4

COMP

5

BOK

Brownout Protection. If the voltage applied to this pin is lower than 2.5V the PWM is disabled.

This pin is typically used for sensing the input voltage of the converter through a resistor divider.

If not used, the pin can be either left floating or connected to Vcc through a 15 k

Ω resistor.

6 to 8

GND

Connection of both the source of the internal MOSFET and the return of the bias current of the

IC. Pins connected to the metal frame to facilitate heat dissipation.

Symbol

Parameter

Value

Unit

Thermal Resistance Junction-ambient (*)

35 to 60

°C/W

Thermal Resistance Junction-pins

15

°C/W

Symbol

Parameter

Value

Unit

Drain Source Voltage

-0.3 to 700

V

Drain Current

0.7

A

IC Supply Voltage

18

V

20

mA

PWM Control Input Sink Current

3

mA

BOK pin Sink Current

1

mA

1.5

W

Operating Junction Temperature

-40 to 150

°C

Storage Temperature

-40 to 150

°C