Datasheet TPS40210, TPS40211 (Texas Instruments) - 10

TPS40210, TPS40211
SLUS772F – MARCH 2008 – REVISED MARCH 2015
www.ti.com 7 Detailed Description 7.1 Overview
The TPS4021x is a peak current-mode control low-side controller with a built in 400-mA gate driver designed to drive n- channel MOSFETs at a fixed frequency. The frequency is adjustable from 35 kHz to 1000 kHz. Small size combined with complete functionality makes the part both versatile and easy to use. The controller uses a low-value current-sensing resistor in series with the power MOSFET's source connection to detect switching current. When the voltage drop across this resistor exceeds 150 mV, the part enters an hiccup fault mode with a time period set by the external soft-start capacitor. The TPS40210 uses voltage feedback to an error amplifier that is biased by a precision 700-mV reference. The TPS40211 has a lower 260-mV reference for higher efficiency in LED drive applications. Internal slope compensation eliminates the characteristic sub-harmonic instability of peak current mode control with duty cycles of 50% or greater. The TPS4021x also incorporates a soft-start feature where the output follows a slowly rising soft-start voltage, preventing output-voltage overshoot. The DIS/EN disables the TPS40210 putting it in a low quiescent current shutdown mode.
7.2 Functional Block Diagram
DIS/EN 3 COMP 4 10 VDD FB 5 + + SS 2 LDO 9 BP E/A 700 mV Soft Start SS Ref and Overcurrent Driver OC Fault PWM 8 GDRV Logic Enable E/A 6 GND Gain = 6 + Oscillator and RC 1 Slope Compensation OC Fault 7 ISNS 150 mV UVLO + LEB UDG-07107 10 Submit Documentation Feedback Copyright © 2008–2015, Texas Instruments Incorporated Product Folder Links: TPS40210 TPS40211 Document Outline 1 Features 2 Applications 3 Description Table of Contents 4 Revision History 5 Pin Configuration and Functions 6 Specifications 6.1 Absolute Maximum Ratings 6.2 ESD Ratings 6.3 Recommended Operating Conditions 6.4 Thermal Information 6.5 Electrical Characteristics 6.6 Typical Characteristics 7 Detailed Description 7.1 Overview 7.2 Functional Block Diagram 7.3 Feature Description 7.3.1 Soft-Start 7.3.2 BP Regulator 7.3.3 Shutdown (DIS/EN Pin) 7.3.4 Minimum On-Time and Off-Time Considerations 7.3.5 Setting the Oscillator Frequency 7.3.6 Synchronizing the Oscillator 7.3.7 Current Sense and Overcurrent 7.3.8 Current Sense and Sub-Harmonic Instability 7.3.9 Current Sense Filtering 7.3.10 Control Loop Considerations 7.3.11 Gate Drive Circuit 7.3.12 TPS40211 7.4 Device Functional Modes 7.4.1 Operation Near Minimum Input Voltage 7.4.2 Operation With DIS/EN Pin 8 Application and Implementation 8.1 Application Information 8.2 Typical Applications 8.2.1 12-V to 24-V Nonsynchronous Boost Regulator 8.2.1.1 Design Requirements 8.2.1.2 Detailed Design Procedure 8.2.1.3 Application Curves 8.2.2 12-V Input, 700-mA LED Driver, Up to 35-V LED String 8.2.2.1 Design Requirements 8.2.2.2 Detailed Design Procedure 9 Power Supply Recommendations 10 Layout 10.1 Layout Guidelines 10.2 Layout Example 11 Device and Documentation Support 11.1 Device Support 11.1.1 Third-Party Products Disclaimer 11.1.2 Related Devices 11.2 Documentation Support 11.2.1 Custom Design with WEBENCH Tools 11.2.2 Receiving Notification of Documentation Updates 11.2.3 References 11.3 Related Links 11.4 Trademarks 11.5 Electrostatic Discharge Caution 11.6 Glossary 12 Mechanical, Packaging, and Orderable Information