ACE3555R

1CH ADJ Current-Limited Power Distribution Switch

VER 1.1

8

Functions Description

Current Limit

The ACE3555R provides a constant current limit that can be programmed by an external resistor. Once

the device reaches its current limit threshold, the internal circuit regulates the gate voltage to hold the

the current limit threshold.

Table 1 Current Limit Threshold Setting

Typical Current Limit (mA)

5.1

1360

5.6

1250

6.8

1020

7.5

930

8.2

870

10

730

12

615

15

500

18

420

30

260

51

160

82

100

100

88

Over Current

When the load exceeds trip current (minimum threshold current triggering constant-current mode) or short

circuited, ACE3555R switches into to constant-current mode (current limit value). ACE3555R will be shut

down only if the overcurrent condition stays long enough to trigger thermal protection.

Trigger overcurrent protection for different overload conditions occurring in applications:

1.

The output has been shorted or overloaded before the device is enabled or input applied. ACE3555R

detects the short or overload and immediately switches into a constant-current mode.

2.

A short or an overload occurs after the device is enabled. The device switches into constant current

mode after the current-limit circuit has been tripped (reached the trip current threshold). However,

high current may flow for a short period of time before the current-limit circuit can react.

3.

Output current has been gradually increased beyond the recommended operating current. The load

current rises until the trip current threshold is reached or until the thermal limit of the device is

exceeded. Once the trip threshold has been reached, the device switches into its constant-current

mode.