LT1528

peculiarity

• Dropout voltage: 0.6V (at I_OUT= 3A)
• Fast transient response
• Output current: 3A
• Quiescent current: 400μA
• No protection diodes are required
• Fixed output voltage: 3.3V
• Under dropout conditions, quiescent current is under control
• Downtime I_Q= 125μA
• Stable with a 3.3μF output capacitor
• Reverse battery protection
• No reverse output current
• Heat limiting function

• description

  LT^®The 1528 is a 3A low dropout regulator optimized to handle high load current transients caused by today's generation of microprocessors. This device has the fastest transient response of any PNP regulator currently available and is very tolerant to deviations in capacitor ESR. At 10mA, the dropout voltage is 75mV, while at 1A and 3A, the dropout voltage rises to 300mV and 600mV, respectively. The device has a quiescent current of 400μA. Quiescent current is well controlled; When the device enters dropout voltage, there is no significant increase in quiescent current. The regulator can operate with output capacitors as small as 3.3μF, but larger output capacitors will be required to achieve the performance required for most microprocessor applications. The LT1528 provides a fixed output voltage of 3.3V. An external SENSE pin allows regulation of output voltages above 3.3V using a simple resistive voltage divider. This enables regulation over a wide output voltage range, including the 3.3V to 4.2V range required by a wide range of processors from companies such as Intel, IBM, AMD, and Cyrix.
  
  The LT1528 combines reverse input and reverse output protection circuitry and includes a shutdown function. In shutdown, quiescent current is reduced to 125μA. The LT1528 is available in 5-lead TO-220 and 5-lead DD-PAK packages.
  

  apply

  • Microprocessor applications
  • Post regulator for switching power supplies
  • 5V to 3.3V logic regulator