L6227Q

Output current capability and IC power dissipation

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Output current capability and IC power dissipation

In Figure 19 and Figure 20 are shown the approximate relation between the output current

and the IC power dissipation using PWM current control driving two loads, for two different

driving types:

–

One full bridge ON at a time (Figure 19) in which only one load at a time is

energized.

–

Two full bridges ON at the same time (Figure 20) in which two loads at the same

time are energized.

For a given output current and driving type the power dissipated by the IC can be easily

evaluated, in order to establish which package should be used and how large must be the

on-board copper dissipating area to guarantee a safe operating junction temperature

(125 °C maximum).

Figure 19.

IC power dissipation vs output current with one full bridge ON at a time

Figure 20.

IC power dissipation versus output current with two full bridges ON at the

same time

No PW M

Test Conditions:

Supply Voltage = 24V

ONE FULL BRIDGE ON AT A TIME

0

0.25 0.5 0.75 1

1.25 1.5

0

2

4

6

8

10

No PWM

Test Conditions:

Supply Volt age =24 V

TWO FULL BRIDGES ON AT THE SAME TIME

0

0.25 0.5 0.75

1

1.25 1.5

0

2

4

6

8

10