LTM4608A

12

4608afa

be used. Forced continuous operation can be enabled by

tying the MODE pin to GND. In this mode, inductor cur-

voltage is in control of the current comparator threshold

throughout, and the top MOSFET always turns on with each

oscillator pulse. During start-up, forced continuous mode is

disabled and inductor current is prevented from reversing

until the LTM4608A’s output voltage is in regulation.

Table 3. Output Voltage Response Versus Component Matrix (Refer to Figure 18) 0A to 3A Load Step

TYPICAL MEASURED VALUES

VALUE

PART NUMBER

VALUE

PART NUMBER

TDK

22μF, 6.3V

C3216X7S0J226M

Sanyo POSCAP

150μF, 10V

10TPD150M

Murata

22μF, 16V

GRM31CR61C226KE15L

PART NUMBER

TDK

100μF, 6.3V

C4532X5R0J107MZ

Sanyo

100μF, 10V

10CE100FH

Murata

100μF, 6.3V

GRM32ER60J107M

(V)

(CERAMIC)

(BULK)*

(CERAMIC)

(BULK)

C1

C3

(V)

DROOP

(mV)

PEAK-TO- PEAK

DEVIATION (mV)

RECOVERY

TIME (μs)

LOAD STEP

(A/μs)

(kΩ)

1.0

10μF

100μF

100μF × 2

None

68pF

None

5

13

26

7

3

14.7

1.0

10μF

100μF

22μF × 1

150μF × 2

None

None

100pF

5

17

34

8

3

14.7

1.0

10μF

100μF

100μF × 2

None

68pF

None

3.3

13

26

7

3

14.7

1.0

10μF

100μF

22μF × 1

150μF × 2

None

None

100pF

3.3

17

34

10

3

14.7

1.0

10μF

100μF

100μF × 2

None

68pF

None

2.7

13

26

7

3

14.7

1.0

10μF

100μF

22μF × 1

150μF × 2

None

None

100pF

2.7

17

34

8

3

14.7

1.2

10μF

100μF

100μF × 2

None

100pF

None

5

16

32

8

3

10

1.2

10μF

100μF

22μF × 1

150μF × 2

None

None

100pF

5

20

41

10

3

10

1.2

10μF

100μF

100μF × 2

None

100pF

None

3.3

16

32

8

3

10

1.2

10μF

100μF

22μF × 1

150μF × 2

None

None

100pF

3.3

20

41

10

3

10

1.2

10μF

100μF

100μF × 2

None

100pF

None

2.7

16

32

10

3

10

1.2

10μF

100μF

22μF × 1

150μF × 2

None

47pF

None

2.7

16

32

8

3

10

1.5

10μF

100μF

100μF × 2

None

100pF

None

5

18

36

8

3

6.65

1.5

10μF

100μF

22μF × 1

150μF × 2

None

None

47pF

5

20

41

12

3

6.65

1.5

10μF

100μF

100μF × 2

None

100pF

None

3.3

16

32

10

3

6.65

1.5

10μF

100μF

22μF × 1

150μF × 2

None

None

47pF

3.3

20

41

12

3

6.65

1.5

10μF

100μF

100μF × 2

None

100pF

None

2.7

18

36

10

3

6.65

1.5

10μF

100μF

22μF × 1

150μF × 2

None

None

None

2.7

20

41

12

3

6.65

1.8

10μF

100μF

100μF × 1

None

47pF

None

5

22

42

8

3

4.87

1.8

10μF

100μF

22μF × 1

150μF × 2

None

None

47pF

5

21

42

12

3

4.87

1.8

10μF

100μF

100μF × 2

None

120pF

None

3.3

21

43

12

3

4.87

1.8

10μF

100μF

22μF × 1

150μF × 2

None

None

47pF

3.3

21

41

12

3

4.87

1.8

10μF

100μF

100μF × 2

None

120pF

None

2.7

22

44

12

3

4.87

1.8

10μF

100μF

22μF × 1

150μF × 2

None

None

None

2.7

21

42

14

3

4.87

2.5

10μF

100μF

100μF × 1

None

100pF

None

5

28

42

10

3

3.09

2.5

10μF

100μF

22μF × 1

150μF × 1

None

22pF

None

5

33

60

10

3

3.09

2.5

10μF

100μF

100μF × 1

None

100pF

None

3.3

30

60

10

3

3.09

2.5

10μF

100μF

22μF × 1

150μF × 1

None

22pF

None

3.3

21

41

10

3

3.09

3.3

10μF

100μF

100μF × 1

100pF

22pF

None

5

38

74

10

3

2.21

3.3

10μF

100μF

22μF × 1

150μF × 1

None

None

None

5

39

75

12

3

2.21

APPLICATIONS INFORMATION

Multiphase Operation

For output loads that demand more than 8A of current,

multiple LTM4608As can be cascaded to run out of phase

to provide more output current without increasing input and

output voltage ripple. The CLKIN pin allows the LTM4608A

to synchronize to an external clock (between 0.75MHz

and 2.25MHz) and the internal phase locked loop allows