Low-Cost Voltage-Mode PWM

Step-Down Controllers

12

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DESIGNATION

VIN = 2.7V TO 5.5V

VOUT = 1.8V, 3A

MAX1966 (FIGURE 3)

VIN = 2.7V TO 5.5V

VOUT = 1.8V, 5A

MAX1966 (FIGURE 3)

C1

1µF ceramic capacitor

1µF ceramic capacitor

C2

Sanyo MV-WX series,

1000µF, 16V,

23m

Ω, 1.82A

Sanyo MV-WX series,

1000µF, 35V,

18m

Ω, 2.77A

C3

Sanyo MV-WX series,

1500µF, 6.3V,

23m

Ω, 1.82A

Sanyo MV-WX series,

1800µF, 16V,

21m

Ω, 2.36A

C4

0.1µF ceramic capacitor

0.1µF ceramic capacitor

C5

0.1µF ceramic capacitor

0.1µF ceramic capacitor

C6

10nF

10nF

C7

0.1µF ceramic capacitor

0.1µF ceramic capacitor

D1

Schottky diode, Central Semiconductor CMPSH-3

Schottky diode, Central Semiconductor CMPSH-3

L1

22µH, 3A, Coilcraft

10µH, 5A, Coilcraft

Dual

Fairchild FDS9926A dual 110m

Ω or International

Rectifier IRF7501 135m

Ω

Fairchild FDS9926A dual

20V, 18m

Ω, 7.5A

R1

1.25k

Ω

1.25k

Ω

R2

1k

Ω

1k

Ω

R3

50k

Ω

50k

Ω

VIN = 4.9V TO 14V

VOUT = 1.8V, 3A

MAX1967 (FIGURE 4)

VIN = 4.9V TO 24V

VOUT = 1.8V, 5A

MAX1967 (FIGURE 4)

C1

1µF ceramic capacitor

1µF ceramic capacitor

C2

220µF 16V, 0.11

Ω ESR,

460mA ripple rated,

Sanyo MV-GX series

Sanyo MV-WX series,

1000µF, 35V,

18m

Ω, 2.77A

C3

470µF 6.3V, 0.11

Ω ESR

Sanyo MV-WX series

C4

0.1µF ceramic capacitor

0.1µF ceramic capacitor

C5

0.1µF ceramic capacitor

0.1µF ceramic capacitor

C6

10nF

10µF

C7

2.2µF ceramic

2.2µF ceramic capacitor

D1

Schottky diode, Central Semiconductor CMPSH-3

Schottky diode, Central Semiconductor CMPSH-3

L1

22µH, 3A, Coilcraft

10µH, 5A, Coilcraft

Dual

Fairchild FDS9926A 110m

Ω, or International Rectifier

IRF7501 135m

Ω

Fairchild FDS6982, 35m

Ω

R1

1.25k

Ω

1.25k

Ω

R2

1k

Ω

1k

Ω

R3

50k

Ω

50k

Ω

R4

10

Ω

10

Ω

Table 1. Component Selection for Standard Applications