Document
T echcode®
2.5A 52KHz 32V PWM Buck DC/DC Converter
DATASHEET
TD2676
General Description
Features
The TD2676 is a 52 KHz fixed frequency monolithic step down switch mode regulator with a built in internal Power MOSFET. It achieves 2.5A continuous output current over a wide input supply range with excellent load and line regulation. The device includes a voltage reference, oscillation circuit, error amplifier, internal PMOS and etc.
The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An enable function, an over current protection function and a short circuit protection function are built inside. An internal compensation block is built in to minimize external component count.
2.5A Constant Output Current 80mΩ RDSON Internal Power PMOSFET Switch Up to 95% Efficiency Fixed 52KHz Frequency Wide 3.6V to 32V Input Voltage Range Output Adjustable from 0.8V to 30V Built in Frequency Compensation Built in Thermal Shutdown Function Built in Current Limit Function SOP-8 Package is Available The minimum dropout up to 0.3V
Applications
The TD2676 serves as ideal power supply units for portable devices.
z z
Portable DVD LCD Monitor / TV
z Battery Charger
z ADSL Modem
z Telecom / Networking Equipment
Package Types
Figure 1. Package Types of TD2676
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T echcode®
2.5A 52KHz 32V PWM Buck DC/DC Converter
Pin Configurations
DATASHEET
TD2676
Figure 2 Pin Configuration of TD2676 (Top View)
Pin Description
Pin Number 1,6, 8 2 3
4
5 7
Pin Name NC Vin SW
GND
FB EN
Description
Not Connect.
Supply Voltage Input Pin. TD2676 operates from a 3.6V to 32V DC voltage. Bypass Vin to GND with a suitably large capacitor to eliminate noise on the input. Power Switch Output Pin. SW is the switch node that supplies power to the output. Ground Pin. Care must be taken in layout. This pin should be placed outside of the Schottky Diode to output capacitor ground path to prevent switching current spikes from inducing voltage noise into TD2676. Feedback Pin. Through an external resistor divider network, FB senses the output voltage and regulates it. The feedback threshold voltage is 0.8V. Enable Pin. EN is a digital input that turns the regulator on or off .Drive EN pin high to turn on the device, drive it low to turn it off.
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T echcode®
2.5A 52KHz 32V PWM Buck DC/DC Converter
Ordering Information
DATASHEET
TD2676
TD2676 □ □
Circuit Type Packing:
Blank:Tube R:Type and Reel Package P: SOP8
Function Block
Figure 3 Function Block Diagram of TD2676
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T echcode®
2.5A 52KHz 32V PWM Buck DC/DC Converter
DATASHEET
TD2676
Absolute Maximum Ratings
Note1: Stresses greater than those listed under Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Parameter Input Voltage Feedback Pin Voltage Enable Pin Voltage Switch Pin Voltage Power Dissipation Operating Junction Temperature Storage Temperature Lead Temperature (Soldering, 10 sec) ESD (HBM) Thermal Resistance‐Junction to Ambient Thermal Resistance‐Junction to Case
Symbol VIN VFB VEN VSW PD TJ TSTG TLEAD
RθJA RθJC
Value -0.3 to 32 ‐0.3 to Vin -0.3 to 12 ‐0.3 to Vin Internally limited
150 ‐65 to 150
260 2000
85 45
Unit V V V V mW ºC ºC ºC
V ºC / W ºC / W
Recommended Operating Conditions
Parameter Input Voltage Operating Junction Temperature Operating Ambient Temperature
Symbol VIN TJ TA
Min. 3.6 -40 -10
Max. 32 125 85
Unit V ºC ºC
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T echcode®
2.5A 52KHz 32V PWM Buck DC/DC Converter
Electrical Characteristics
DATASHEET
TD2676
Specifications with boldface type are for full operationg temperature range, the other type are for TJ=25OC. Note1: Thermal resistance with copper area of approximately 3 in2.
Parameters
Symbol
Test Condition Min.
Typ.
Max. Unit
Input voltage Shutdown Supply C.