UCC3588

5BIT PROGRAMMABLE OUTPUT BiCMOS

POWER SUPPLY CONTROLLER

SLUS311A – JULY 1999 – REVISED AUGUST 2000

10

POST OFFICE BOX 655303

APPLICATION INFORMATION

Table 2. Regulator Operating Conditions

VIN=

4.5

5.0

5.5

VOUT=3.5

Total input cap RMS current

Total input cap power dissipation

Total power dissipation

Power train efficiency

4.40

0.21

5.10

0.89

5.20

0.29

5.30

0.88

5.60

0.34

5.40

0.87

VOUT=1.8

Total input cap RMS current

Total input cap power dissipation

Total power dissipation

Power train efficiency

6.00

0.39

5.20

0.81

5.90

0.39

5.30

0.80

5.80

0.37

5.40

0.80

Figure 1

100.0

10.0

1.0

–50

–40

–20

–10

10

20

–60

V

IN

= 5.5 V

V

IN

= 4.5 V

1000.0

0.1

–30

0

GAIN

vs

FREQUENCY

Frequency - kHz

Figure 2

100.0

10.0

1.0

–50

–40

–20

–10

10

20

–60

1000.0

0.1

–30

0

Frequency - kHz

PHASE

vs

FREQUENCY

To compensate the loop with as high a bandwidth as practical, additional gain is added to the loop with the

voltage error amplifier.