Ultracompact, 1 A Thermoelectric Cooler (TEC) Driver for Digital Control Systems Data Sheet ADN8833 FEATURES FUNCTIONAL BLOCK DIAGRAM VTEC ITEC VDD Patented high efficiency single inductor architecture Integrated low RDSON MOSFETs for TEC driver ADN8833 TEC voltage and current operation monitoring TEC CURRENT VLIM/SD No external sense resistor required AND VOLTAGE ILIM SENSE AND LIMIT LINEAR Independent TEC heating and cooling current limit settings LDR POWER STAGE Programmable maximum TEC voltage 2 MHz PWM driver switching frequency External synchronization PVIN CONT CONTROLLER Digital thermal control loop compatible PWM 2.50 V reference output with 1% accuracy SW POWER STAGE Available in a 25-ball, 2.5 mm 2.5 mm WLCSP or in a 24-lead, 4 mm 4 mm LFCSP VOLTAGE APPLICATIONS OSCILLATOR REFERENCE TEC temperature control Optical modules AGND VREF SFB EN/SY PGNDx Optical fiber amplifiers Figure 1. Optical networking systems Instruments requiring TEC temperature control The internal 2.5 V reference voltage provides a 1% accurate GENERAL DESCRIPTION output that is used to bias a voltage divider network to program the 1 The ADN8833 is a monolithic H-bridge TEC driver with maximum TEC current and voltage limits for both the heating integrated 1 A power MOSFETs. It has a linear power stage with and cooling modes. It can also be a reference voltage for the DAC the linear driver (LDR) output and a pulse-width modulation and the temperature sensing circuit, including a thermistor bridge (PWM) power stage with the SW output. Depending on the and an analog-to-digital converter (ADC). control voltage at the CONT input, the ADN8833 drives current through a TEC to settle the temperature of a laser diode or a passive Table 1. TEC Family Models component attached to the TEC module to the programmed Model MOSFET Thermal Loop Package target temperature. ADN8831 Discrete Digital/analog LFCSP (CP-32-7) The control voltage applied to the CONT input is generated by a ADN8833 Integrated Digital WLCSP (CB-25-7), LFCSP (CP-24-15) digital-to-analog converter (DAC) closing the digital proportional, ADN8834 Integrated Digital/analog WLCSP (CB-25-7), integral, derivative (PID) loop of temperature control system. LFCSP (CP-24-15) 1 Product is covered by US Patent No. 6,486,643. Rev. B Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20152018 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. 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Technical Support www.analog.com 12909-001ADN8833 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 TEC Voltage/Current Monitor ................................................. 15 Applications ....................................................................................... 1 Maximum TEC Voltage Limit .................................................. 15 Functional Block Diagram .............................................................. 1 Maximum TEC Current Limit ................................................. 15 General Description ......................................................................... 1 Applications Information .............................................................. 16 Revision History ............................................................................... 2 Typical Application with Digital PID Using a DAC .............. 16 Specif ications ..................................................................................... 3 Thermistor Setup ........................................................................ 16 Absolute Maximum Ratings ............................................................ 6 MOSFET Driver Amplifiers ...................................................... 16 Thermal Resistance ...................................................................... 6 PWM Output Filter Requirements .......................................... 17 ESD Caution .................................................................................. 6 Input Capacitor Selection .......................................................... 18 Pin Configurations and Function Descriptions ........................... 7 Power Dissipation....................................................................... 18 Typical Performance Characteristics ............................................. 8 PCB Layout Guidelines .................................................................. 20 Detailed Functional Block Diagram ............................................ 12 Block Diagrams and Signal Flow ............................................. 20 Theory of Operation ...................................................................... 13 Guidelines for Reducing Noise and Minimizing Power Loss .... 20 Digital PID Control .................................................................... 13 Example PCB Layout Using Two Layers ................................. 21 Powering the Driver ................................................................... 13 Outline Dimensions ....................................................................... 23 Enable and Shutdown ................................................................ 14 Ordering Guide .......................................................................... 23 Oscillator Clock Frequency ....................................................... 14 Soft Start on Power-Up .............................................................. 14 REVISION HISTORY 8/ 2018Rev. A to Rev. B Added Patent Information .............................................................. 1 8/ 2015Rev. 0 to Rev. A Added 24-Lead LFCSP ....................................................... Universal Changes to Features Section and Table 1 ...................................... 1 Changes to Table 2 ............................................................................ 3 Changes to Table 3 ............................................................................ 6 Added Figure 3 Renumbered Sequentially ................................. 7 Changes to Figure 11 ........................................................................ 9 Changes to Figure 18 and Figure 19 ............................................. 10 Changes to Figure 23 ...................................................................... 12 Changes to Powering the Driver Section and Figure 24 Caption ... 13 Change to Soft Start on Power-Up Section ................................. 14 Changes to Table 7 .......................................................................... 17 Added Table 8 Renumbered Sequentially .................................. 18 Updated Outline Dimensions ....................................................... 23 Changes to Ordering Guide ......................................................... 23 4/2015Revision 0: Initial Version Rev. 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