特点
1.5A Switch in a Small MSOP-8 Package
Constant 1.25MHz Switching Frequency
High Power Exposed Pad (MS8E) Package
Wide Operating Voltage Range: 3V to 25V
High Efficiency 0.22 Ohm Switch
1.2V Feedback Reference Voltage
Fixed Output Voltages of 1.8V, 2.5V, 3.3V, 5V
2% Overall Output Tolerance
Uses Low Profile Surface Mount Components
Low Shutdown Current: 6μA
Synchronizable to 2MHz
Current Mode Loop Control
Constant Maximum Switch Current Rating at All Duty Cycles*
典型应用
典型应用
描述
The LT?1767 is a 1.25MHz monolithic buck switching regulator. A high efficiency 1.5A, 0.22 Ohm switch is included on the die together with all the control circuitry required to complete a high frequency, current mode switching regulator. Current mode control provides fast transient response and excellent loop stability.
New design techniques achieve high efficiency at high switching frequencies over a wide operating range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li-Ion batteries. An operating supply current of 1mA improves efficiency, especially at lower output currents. Shutdown reduces quiescent current to 6μA. Maximum switch current remains constant at all duty cycles. Synchronization allows an external logic level signal to increase the internal oscillator from 1.4MHz to 2MHz.
The LT1767 is available in an 8-pin MSOP fused leadframe package and a low thermal resistance exposed pad package. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of chip inductors.