LM2642中文资料4.5V 至 30V 两相峰值电流模式同步降压控制器数据手册TI规格书

描述 Description

The LM2642 consists of two current mode synchronous buck regulator controllers with a switching frequency of 300kHz.The two switching regulator controllers operate 180° out of phase. This feature reduces the input ripple RMS current, thereby significantly reducing the required input capacitance. The two switching regulator outputs can also be paralleled to operate as a dual-phase single output regulator.The output of each channel can be independently adjusted from 1.3 to VIN
• maximum duty cycle. An internal 5V rail is also available externally for driving bootstrap circuitry.Current-mode feedback control assures excellent line and load regulation and a wide loop bandwidth for excellent response to fast load transients. Current is sensed across either the Vds of the top FET or across an external current-sense resistor connected in series with the drain of the top FET. Current limit is independently adjustable for each channel.The LM2642 features analog soft-start circuitry that is independent of the output load and output capacitance. This makes the soft-start behavior more predictable and controllable than traditional soft-start circuits.A PGOOD1 pin is provided to monitor the dc output of channel 1. Over-voltage protection is available for both outputs. A UV-Delay pin is also available to allow delayed shut off time for the IC during an output under-voltage event.

特性 Features

• Two Synchronous Buck Regulators
• 180° Out of Phase Operation
• 4.5V to 30V Input Range
• Power Good Function Monitors Ch.1
• 37µA Shutdown Current
• 0.04% (typical) Line and Load Regulation Error
• Current Mode Control With or Without a Sense Resistor
• Independent Enable/Soft-start Pins Allow Simple Sequential Startup Configuration.
• Configurable for Single Output Parallel Operation.
• Adjustable Cycle-by-Cycle Current Limit
• Input Under-voltage Lockout
• Output Over-voltage Latch Protection
• Output Under-voltage Protection with Delay
• Thermal Shutdown
• Self Discharge of Output Capacitors When the Regulator is OFF
• TSSOP package