Layout Guidelines

Good thermal contact between the MAX5900/

MAX5901 and the external MOSFET is essential for the

thermal shutdown feature to operate effectively. Place

the MAX5900/MAX5901 as close as possible to the

drain of the external MOSFET, and use wide circuit

board traces for good heat transfer. See Figure 5 for an

example of a PC board layout.

Chip Information

TRANSISTOR COUNT: 678

PROCESS: BiCMOS

-100V, SOT23/TDFN, Simple Swapper

Hot-Swap Controllers

_______________________________________________________________________________________

9

Figure 5. Circuit Board Layout Example

GROUND

POWER IN

POWER

OUT

M1

SOT-223

SDG

U1

SOT23-6

MAX5900/MAX5901

V

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

100

µF

MAX5900

MAX5901

100k

Ω

V

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

V

50k

Ω

MAX5900

MAX5901

V

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

MAX5900

MAX5901

100k

Ω

V

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

48V

MAX5900A

MAX5901A

50k

Ω

SCOPE

SCOPE

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

48V

MAX5900

MAX5901

50k

Ω

SCOPE

SCOPE

SCOPE

SCOPE

SCOPE

+

-

GND

ON/OFF

GATE

DRAIN

PGOOD

(PGOOD)

48V

MAX5900

MAX5901

50k

Ω

50k

Ω

SCOPE SCOPE

SCOPE

(a) SUPPLY CURRENT

(c) GATE DRIVE VOLTAGE

(e) TURN-ON WAVEFORMS

(d) RETRY TIMEOUT

(f) CIRCUIT-BREAKER EVENT

Figure 6. Test Circuits