LM20145QMHXSLASHNOPB.A中文资料德州仪器数据手册PDF规格书

FEATURES

• Available in AEC-Q100 Temperature Grade 1

• Input Voltage Range 2.95V to 5.5V

• Accurate Current Limit Minimizes Inductor

Size

• 97% Peak Efficiency

• Adjustable Switching Frequency (250 kHz to

750 kHz)

• 32 mΩ Integrated FET Switches

• Starts up into Pre-Biased Loads

• Output Voltage Tracking

• Peak Current Mode Control

• Adjustable Output Voltage down to 0.8V

• Adjustable Soft-Start with External Capacitor

• Precision Enable Pin with Hysteresis

• Integrated OVP, UVLO, Power Good and

Thermal Shutdown

• HTSSOP 16-Pin Exposed Pad Package

APPLICATIONS

• Simple to Design, High Efficiency Point of

Load Regulation from a 5V or 3.3V Bus

• High Performance DSPs, FPGAs, ASICs and

Microprocessors

• Broadband, Networking and Optical

Communications Infrastructure

DESCRIPTION

The LM20145 is a full featured adjustable frequency

synchronous buck regulator capable of delivering up

to 5A of continuous output current. The current mode

control loop can be compensated to be stable with

virtually any type of output capacitor. For most cases,

compensating the device only requires two external

components, providing maximum flexibility and ease

of use. The device is optimized to work over the input

voltage range of 2.95V to 5.5V making it suited for a

wide variety of low voltage systems.

The device features internal over voltage protection

(OVP) and over current protection (OCP) circuits for

increased system reliability. A precision enable pin

and integrated UVLO allows the turn-on of the device

to be tightly controlled and sequenced. Start-up

inrush currents are limited by both an internally fixed

and externally adjustable Soft-Start circuit. Fault

detection and supply sequencing is possible with the

integrated power good circuit.

The LM20145 is designed to work well in multi-rail

power supply architectures. The output voltage of the

device can be configured to track a higher voltage rail

using the SS/TRK pin. If the output of the LM20145 is

pre-biased at startup it will not sink current to pull the

output low until the internal soft-start ramp exceeds

the voltage at the feedback pin.

The frequency of this device can be adjusted from

250 kHz to 750 kHz by connecting an external

resistor from the RT pin to ground.

The LM20145 is offered in a 16-pin HTSSOP

package with an exposed pad that can be soldered to

the PCB, eliminating the need for bulky heatsinks.