TECHNICAL INFORMATION

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TA2020-020, Rev. 4.0, 09.00

pin to be pulled up through a large valued resistor (1M

mode, the sleep pin should be grounded.

Fault Pin

The FAULT pin is a 5V logic output that indicates various fault conditions within the device. These

conditions include: low supply voltage, low charge pump voltage, low 5V regulator voltage, over

current at any output, and junction temperature greater than approximately 155

°C. The FAULT

output is capable of directly driving an LED through a series 200

Ω. The FAULT output is capable of

directly driving an LED through a series 200

Ω resistor. If the FAULT pin is connected directly to the

MUTE input an automatic reset will occur in the event of an over-current condition.

Heat Sink Requirements

In some applications it may be necessary to fasten the TA2020-020 to a heat sink. The determining

factor is that the 150

by the following equation:

)

JA

A

)

MAX

(

J

T

T

θ

−

where…

Example:

What size heat sink is required to operate the TA2020-020 at 20W per channel continuously in a

70ºC ambient temperature?

Efficiency =

IN

OUT

P

P

=

DISS

OUT

OUT

P

P

P

−

W

5

20

8

.

0

20

P

P

OUT

OUT

=

−

=

−

η

)

DISS

A

)

MAX

(

J

P

T

T

−

=

10

70

150

−

= 8

°C/W

B