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L6590

PIN FUNCTIONS

THERMAL DATA

(*) Value depending on PCB copper area and thickness

.

ABSOLUTE MAXIMUM RATINGS

Pin#

Name

Description

L6590

L6590D

1

1

DRAIN

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

generator sinks current from this pin.

2

2, 3

N.C.

Not internally connected. Provision for clearance on the PCB.

34

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.

47

COMP

Output of the Error Amplifier. Used for control loop compensation or to directly control

PWM with an optocoupler.

5

8

VFB

Inverting input of the Error Amplifier. The non-inverting one is internally connected to a

2.5V± 2% reference. This pin can be grounded in some feedback schemes.

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.

-

6

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.

-

5

SGND

Current return for the bias current of the IC.

-

9 to 16

PGND

Connection of the source of the internal MOSFET. Pins connected to the metal frame to

facilitate heat dissipation.

Symbol

Parameter

Minidip

SO16W

Unit

Thermal Resistance Junction to ambient (*)

35 to 60

40 to 65

°C/W

Thermal Resistance Junction to pins

15

20

°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

Error Amplifier Ouput Sink Current

3

mA

Voltage on Feedback Input

5

V

BOK pin Sink Current

1

mA

1.5

W

Operating Junction Temperature

-40 to 150

°C

Storage Temperature

-40 to 150

°C