Analog Devices LTC1470 Product Info

• Single 3.3V/5V Switch in 8-Pin SO Package
• Dual 3.3V/5V Switch in 16-Pin SO Package
• Built-In Current Limit and Thermal Shutdown
• Built-In Charge Pumps (No 12V Required)
• Extremely Low R_DS(ON) MOSFET Switches
• Output Current Capability: 1A
• Inrush Current Limited (Drives 150µF Loads)
• Quiescent Current in Standby: 1µA
• No Parasitic Body Diodes
• Built-In XOR Function Eliminates “Glue” Logic
• Break-Before-Make Switching
• Controlled Rise and Fall Times

The LTC1470 switches the V_CC pins of a Personal Computer Memory Card International Association (PCMCIA) card slot between three operating states: OFF, 3.3V and 5V. Two low R_DS(ON) N-channel power MOSFETs are driven by a built-in charge pump which generates a voltage higher than the supply voltage to fully enhance each switch when selected by the input control logic.

The LTC1470 inputs are compatible with industry standard PCMCIA controllers. A built-in XOR ensures that both switches are never on at the same time. This function also makes the LTC1470 compatible with both active-low and active-high controllers (see Applications Information section). The switch rise times are controlled to eliminate power supply glitching.

The LTC1470 features built-in SafeSlot^™ current limit and thermal shutdown. The output is limited to 1A during short circuit to ground but 2A of peak operating current is allowed.

The LTC1471 is a dual version of the LTC1470 and is available in a 16-pin SO package.

Applications

• Notebook Computers
• Palmtop Computers
• Pen-Based Computers
• Handi-Terminals
• PC Card Reader/Writers
• 3.3V/5V Power Supply Switch