MAX1940EEE+ Maxim Integrated Products, MAX1940EEE+ Datasheet - Page 8

• Manufacturer Part Number: MAX1940EEE+
• Description: IC SW USB TRPL 16-QSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1940EEE+

• Applications: USB, Peripherals
• Current - Supply: 60µA
• Voltage - Supply: 4 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-QSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX1940 triple current-limited USB power switch
provides three independent switches, each with its own
enable-control input and fault indicator (see Figure 1).
A logic input sets the active polarity of the enable con-
trol inputs. The fault indicators notify the system when
the current-limit, short-circuit, undervoltage lockout, or
thermal-shutdown threshold is exceeded.
The MAX1940 operates from a 4V to 5.5V input supply
and supplies a minimum output current of 700mA per
channel. A built-in current limit of 0.9A (typ) limits the
output current in the event of an overload condition.
Built-in short-circuit detection pulses the output current if
Triple USB Switch with Autoreset and
Fault Blanking
Figure 1. Functional Diagram
8
_______________________________________________________________________________________
ONC
ONA
ONB
SEL
IN1
Detailed Description
MAX1940
UVLO
20ms TIMERS
FAULT LOGIC
SHUTDOWN
THERMAL
CHARGE
PUMP
25kHz
GND
OSC
the output voltage falls below 1V, resulting in lower RMS
output current and reduced power dissipation in the
device. Independent thermal shutdown allows normal
operation to continue if one channel experiences a pro-
longed overload or short-circuit condition.
Low-R
vide three switches in the space-saving 16-pin QSOP
package. An internal micropower charge pump gener-
ates the high-side supply needed for driving the gates
of these high-side switches. Separate current-limiting
and thermal-shutdown circuitry permits each switch to
operate independently, improving system robustness.
BIAS
REF
(SEE SWITCH A)
ON
SWITCH B
25mA
NMOS switches enable the MAX1940 to pro-
IN2 IN3
IN2
ILIM
(EXPANDED)
(SEE SWITCH A)
SWITCH A
SWITCH C
IN4
IN5
FAULTA
OUTA
OUTB
FAULTB
OUTC
FAULTC
IN_