Features: Guaranteed Current Limit: 200mA, 250mA, 300mA
Thermal-Shutdown Protection
Reverse Current Protection
0.2Ω On-Resistance
14ms Guaranteed Blanking Time
FLAG Function (MAX4789/MAX4791/MAX4793)
80µA Supply Current
8µA Latch-Off Current (MAX4789/MAX4791/MAX4793)
0.01µA Shutdown Current
2.3V to 5.5V Supply Range
Undervoltage Lockout
Fast Current-Limit Response Time (5µs)
Tiny QFN and SOT23/SOT143 PackagesApplicationPDAs and Palmtop Devices
Cell Phones
GPS Systems
Hand-Held Devices
SDIOPinoutSpecificationsIN, ON, FLAG , OUT to GND.........................................-0.3V to +6V
OUT Short Circuit to GND...................................Internally Limited
Continuous Power Dissipation (TA = +70°C)
4-Pin SOT143 (derate 4.0mW/°C above +70°C)............320mW
5-Pin SOT23 (derate 7.1mW/°C above +70°C)..............571mW
6-Pin Thin QFN (derate 24.4mW/°C above +70°C)...1951.2mW
Operating Temperature Range .........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range ..........................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................+300°CDescriptionThe MAX4791 family of switches feature internal current limiting to prevent damage to host devices due to faulty load conditions. The MAX4791 has a low 0.2Ω on-resistance and operate from 2.3V to 5.5V input voltage range. They are available with guaranteed 200mA, 250mA, and 300mA current limits, making them ideal for SDIO and other load switching applications.
When the switch is on and a load is connected to the port, a guaranteed blanking time of 14ms ensures that the transient voltages settle down. If after this blanking time the load current is greater than the current limit, the MAX4789, MAX4791, and MAX4793 enter a latch-off state where the switch is turned off and FLAG is issued to the microprocessor. The switch can be turned on again by cycling the power or the ON pin.
The MAX4791 has an autoretry feature where the switch turns off after the blanking time and then continuously checks to see if the overload condition is present. The switch remains on after the overload condition disappears.
The MAX4789MAX4794 are available in 6-pin thin QFN and tiny space-saving 4-pin SOT143 packages. The MAX4789/MAX4791/MAX4793 are also available in a tiny 5-pin SOT23 package. For lower current current-limiting switches, refer to the MAX4785MAX4788 data sheet.