Technical Reference Notes

ALQ15XX48X Series

(Open Frame Dual Output Quarter Brick)

MODEL: ALQ15 SERIES

SHEET 10 OF 19

MARCH 4, 2004 - REVISION 01

Basic Operation and Features (continued)

TABLE 1-C

TABLE 1-D

ALQ15GM48 (2.5V / 1.5V)

ALQ15FG48N-6D*

? [%}

? [%}

? [%}

? [%}

+1

70.46

-1

70.31

+1

46.84

-1

66.47

+2

29.65

-2

32.75

+2

20.82

-2

27.32

+3

17.00

-3

19.42

+3

12.14

-3

15.55

+4

10.83

-4

12.58

+4

7.81

-4

9.87

+5

7.18

-5

8.43

+5

5.20

-5

6.53

+6

4.77

-6

5.64

+6

3.47

-6

4.34

+7

3.06

-7

3.63

+7

2.23

-7

2.78

+8

1.78

-8

2.12

+8

1.30

-8

1.62

+9

0.79

-9

0.94

+9

0.58

-9

0.72

+10

0.00

-10

0.00

+10

0.00

-10

0.00

* DI/DT’s QD48T025033 Trim Equivalent

ALQ15 standard trim utilizes approximately similar range of trim resistors for both RTRIM-UP and RTRIM-DOWN to adjust

the outputs. This facilitates ease of resistor selection and contributes to a decreased number of parts for customer inventory if

the TRIM pin is being utilized.

OUTPUT ENABLE

The ALQ15 comes with an Enable pin (PIN 2), which is primarily used to turn ON/OFF the converter. Both a Positive (no part

number suffix required) and a Negative (suffix “N” required) Enable Logic options are being offered. Please refer to Table 2

for the Part Numbering Scheme.

For Positive Enable, the converter is turned on when the Enable pin is at logic HIGH or left open. The unit turns off when the

OUTPUT OVER VOLTAGE PROTECTION (OVP)

The Over Voltage Protection circuit will shut down the entire converter if any of the two output voltages exceeds the OVP

threshold limits. The converter will automatically recover once the fault is removed.

OVER CURRENT PROTECTION (OCP)

The Over Current Protection circuit will shutdown the converter if any of the load current of either output reaches the OCP

threshold limits. The unit will automatically recover once the over current condition is removed. See Figure 12 for typical

output characteristic under an over current condition.

OVER TEMPERATURE PROTECTION (OTP)

The Over Temperature Protection circuit will shutdown the converter once the sensed location reaches the OTP range. This

feature prevents the unit from overheating and consequently going into thermal runaway, which may further damage the

converter and the end system. Such overheating may be an effect of operation outside the given power thermal derating

conditions. Restart is possible once the temperature of the sensed location drops to less than 110

°C.