Dual USB Switch with Fault Blanking

and Autoreset

_______________________________________________________________________________________

7

1ms/div

µF

5V

5V

0

1V

2V

3V

4V

0

MAX1838 toc17

Typical Operating Characteristics (continued)

°C, unless otherwise noted.)

1ms/div

SWITCH TURN-OFF TIME,

MAX1838 toc18

5V

5V

0

1V

2V

3V

4V

0

1ms/div

START-UP TIME INTO 10

ΩLOAD

4V

5V

0

0.5A

0

2V

0

MAX1838 toc19

Pin Description

PIN

NAME

FUNCTION

1, 8

GND

Ground. Connect both GND pins together.

2

SEL

power from IN source, low for power from AUX source.

3, 6

AUXA, AUXB

Auxiliary Input. Connect both AUX pins together and bypass with a 0.1µF capacitor to ground.

Load conditions may require additional bulk capacitance to maintain AUX voltage regulation.

4, 5

INA, INB

Power Input. Connect both IN pins together and bypass with a 0.1µF capacitor to GND. Load

conditions may require additional bulk capacitance to maintain the IN voltage regulation.

7

ON

Control Input. A logic low at

ON turns on the device. A logic high shuts off both outputs and all

power to internal circuits. Driving

ON higher than IN does not cause damage.

9

FAULTB

Fault Indicator Output for Channel B. This open-drain output goes low when channel B is in

thermal shutdown or in undervoltage lockout or in a sustained (>20ms) current-limit or short-circuit

condition.

10

ADJB

Current-Limit Adjust for Channel B. When operating from auxiliary input, adjust the current limit by

connecting a resistor from ADJB to GND as shown in Programmable Current Limit.

11, 12

OUTB1, OUTB2

Power Output B. Connect both OUTB_ pins together. Connect a 1µF or greater capacitor from

OUTB_ to ground. Load condition may require additional bulk capacitance.

13, 14

OUTA1, OUTA2

Power Output A. Connect both OUTA_ pins together. Connect a 1µF or greater capacitor from

OUTA_ to ground. Load condition may require additional bulk capacitance.