Features

• 1mA I_Q at 250kHz
• Uses Small Inductors: 15µH
• All Surface Mount Components
• Only 0.6 Square Inch of Board Space
• Low Minimum Supply Voltage: 2.7V
• Constant Frequency Current Mode
• Current Limited Power Switch: 1.5A
• Regulates Positive or Negative Outputs
• Shutdown Supply Current: 12µA Typ
• Easy External Synchronization
• 8-Pin SO or PDIP Packages

Typical Application

Description

The LT1373 is a low supply current high frequency current mode switching regulator. It can be operated in all standard switching configurations including boost, buck, flyback, forward, inverting and “Cuk.” A 1.5A high efficiency switch is included on the die, along with all oscillator, control and protection circuitry. All functions of the LT1373 are integrated into 8-pin SO/PDIP packages. Compared to the 500kHz LT1372, which draws 4mA of quiescent current, the LT1373 switches at 250kHz, typically consumes only 1mA and has higher efficiency. High frequency switching allows for small inductors to be used. All surface mount components consume less than 0.6 square inch of board space. New design techniques increase flexibility and maintain ease of use. Switching is easily synchronized to an external logic level source. A logic low on the shutdown pin reduces supply current to 12µA. Unique error amplifier circuitry can regulate positive or negative output voltage while maintaining simple frequency compensation techniques. Nonlinear error amplifier transconductance reduces output overshoot on start-up or overload recovery. Oscillator frequency shifting protects external components during overload conditions.