
Micrel
General Description
The MIC2557 switches the four voltages required by PCMCIA (Personal Computer Memory Card International Association) card VPP Pins. The MIC2557 provides selectable 0V, 3.3V, 5.0V, or 12.0V (±5%) from the system power supply to VPP1 or VPP2. Output voltage is selected by two digital inputs. Output current ranges up to 120mA. Four control states, VPP, VCC, high impedance, and active logic low are available. An auxiliary control input determines whether the high impedance (open) state or low logic state is asserted.
FEATUREs
• Complete PCMCIA VPP Switch Matrix in a Single IC
• No External Components Required
• Digital Selection of 0V, VCC, VPP, or High Impedance Output
• No VPP OUT Overshoot or Switching Transients
• Break-Before-Make Switching
• Low Power Consumption
• 120mA VPP (12V) Output Current
• Optional Active Source Clamp for Zero Volt Condition
• 3.3V or 5V Supply Operation
• 8-Pin SOIC Package
APPLICATIONs
• PCMCIA VPP Pin Voltage Switch
• Power Supply Management
• Power Analog Switch