Sample & Buy Product Folder Support & Community Tools & Software Technical Documents Reference Design LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 LM5032 High-Voltage Dual Interleaved Current Mode Controller 1 Features 3 Description • • • • • • • The LM5032 dual current mode PWM controller contains all the features needed to control either two independent forward dc/dc converters or a single high current converter comprised of two interleaved power stages. The two controller channels operate 180° out of phase thereby reducing input ripple current. The LM5032 includes a startup regulator that operates over a wide input range up to 100 V and compound (bipolar + CMOS) gate drivers that provide a robust 2.5-A peak sink current. The adjustable maximum PWM duty cycle reduce stress on the primary side MOSFET switches. Additional features include programmable line undervoltage lockout, cycle-bycycle current limit, hiccup mode fault operation with adjustable response time, PWM slope compensation, soft-start, and a 2-MHz capable oscillator with synchronization capability. 1 • • • • • • • Two Independent PWM Current Mode Controllers Integrated High-Voltage Startup Regulator Compound 2.5-A Main Output Gate Drivers Single Resistor Oscillator Setting to 2 MHz Synchronizable Oscillator Programmable Maximum Duty Cycle Maximum Duty Cycle Fold-Back at High-Line Voltage Adjustable Timer for Hiccup Mode Current Limiting Integrated Slope Compensation Adjustable Line Undervoltage Lockout Independently Adjustable Soft-Start (Each Regulator) Direct Interface with Opto-Coupler Transistor Thermal Shutdown TSSOP 16-Pin Package PART NUMBER LM5032 PACKAGE BODY SIZE (NOM) TSSOP (16) 5.00 mm x 4.40 mm (1) For all available packages, see the orderable addendum at the end of the datasheet. 2 Applications • • • Device Information(1) Telecommunication Power Converters Industrial Power Converters 42-V Automotive Systems Typical Application Circuit VCC VPWR 36V to 75V Input 3.3V VIN LM5032 UVLO CS1 OUT1 RES Sync ERROR AMP & ISOLATION RT COMP1 DCL 2.5V CS2 VCC OUT2 SS2 ERROR AMP & ISOLATION SS1 COMP2 GND1 GND2 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 3 4 6.1 6.2 6.3 6.4 6.5 6.6 4 4 4 5 5 8 Absolute Maximum Ratings ...................................... ESD Ratings ............................................................ Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics........................................... Typical Characteristics .............................................. 7.3 Feature Description................................................. 12 7.4 Device Functional Modes........................................ 17 8 Application and Implementation ........................ 18 8.1 Application Information............................................ 18 8.2 Typical Application ................................................. 23 9 Power Supply Recommendations...................... 27 10 Layout................................................................... 27 10.1 Layout Guidelines ................................................. 27 10.2 Layout Example .................................................... 28 11 Device and Documentation Support ................. 28 Detailed Description ............................................ 10 11.1 Trademarks ........................................................... 28 11.2 Electrostatic Discharge Caution ............................ 28 11.3 Glossary ................................................................ 28 7.1 Overview ................................................................. 10 7.2 Functional Block Diagram ....................................... 11 12 Mechanical, Packaging, and Orderable Information ........................................................... 28 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision A (April 2013) to Revision B • Added Pin Configuration and Functions section, Handling Rating table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section ................................................................................................................................................................................... 1 Changes from Original (April 2013) to Revision A • 2 Page Page Changed layout of National Data Sheet to TI format ........................................................................................................... 27 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 5 Pin Configuration and Functions PW Package 16-Pin TSSOP Top View 1 2 3 4 5 6 7 8 VIN RT/SYNC COMP1 CS1 DCL COMP2 SS1 CS2 UVLO SS2 VCC RES OUT1 OUT2 GND1 GND2 16 15 14 13 12 11 10 9 Pin Functions PIN I/O DESCRIPTION APPLICATIONS INFORMATION NO. NAME 1 VIN P Input Supply Input to the startup regulator. The operating input range is 13 V to 100 V with transient capability to 105 V. 2 COMP1 I PWM Control, Controller 1 The COMP1 input provides voltage feedback to the PWM comparator inverting input of Controller 1 through a 3:1 divider. The OUT1 duty cycle increases as the COMP1 voltage increases. An internal 5-KΩ pull-up resistor to 5.0-V provides bias current to an opto-coupler transistor. 3 CS1 I Current Sense Input, Controller 1 Input for current mode control and the current limit sensing. If the CS1 pin exceeds 0.5V the OUT1 pulse is terminated producing cycle-by-cycle current limiting. External resistance connected to CS1 will adjust (increase) PWM slope compensation. This pin's voltage must not exceed 1.25V. 4 SS1 I Soft-start, Controller 1 An internal 50-µA current source charges an external capacitor to set the soft-start rate. During a current limit restart sequence, the internal current source is reduced to 1 µA to increase the delay before retry. Forcing SS1 below 0.5 V shuts off Controller 1. 5 UVLO I VIN Under-Voltage Lockout An external resistor divider sets the input voltage threshold to enable the LM5032. The UVLO comparator reference voltage is 1.25 V. A switched 20-µA current source provides adjustable UVLO hysteresis. The UVLO pin voltage also controls the maximum duty cycle as described in the Feature Description section. 6 VCC P Start-up regulator output Output of the 7.7-V high-voltage start-up regulator. Current limit is a minimum of 19 mA. 7 OUT1 O Main Gate Driver, Controller 1 Gate driver output to the primary side switch for Controller 1. OUT1 swings between VCC and GND1 at a frequency equal to half the oscillator frequency. 8 GND1 G Ground, Controller 1 Ground connection for Controller 1 including gate driver, PWM controller, soft-start and support functions. 9 GND2 G Ground, Controller 2 Ground connection for Controller 2 including the gate driver, PWM controller and soft-start. 10 OUT2 O Main Gate Driver, Controller 2 Gate driver output to the primary side switch for Controller 2. OUT2 swings between VCC and GND2 at a frequency equal to half the oscillator frequency. 11 RES I Hiccup mode restart adjust An external capacitor sets the time delay before forced restart during a sustained period of cycle-by-cycle current limiting. The hiccup mode comparator threshold is 2.55 V. Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 3 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Pin Functions (continued) PIN I/O DESCRIPTION APPLICATIONS INFORMATION NO. NAME 12 SS2 I Soft-start, Controller 2 An internal 50-µA current source charges an external capacitor to set the soft-start rate. During a current limit restart sequence, the internal current source is reduced to 1 µA to increase the delay before retry. Forcing SS2 below 0.5 V shuts off Controller 2. 13 CS2 I Current Sense Input, Controller 2 Input for current mode control and the current limit sensing. If the CS2 pin exceeds 0.5 V the OUT2 pulse is terminated producing cycle-by-cycle current limiting. External resistance connected to CS2 will adjust (increase) PWM slope compensation. This pin's voltage must not exceed 1.25V. 14 COMP2 I PWM Control, Controller 2 The COMP2 input provides voltage feedback to the PWM comparator inverting input of Controller 2 through a 3:1 divider. The OUT2 duty cycle increases as the COMP2 voltage increases. An internal 5kΩ pull-up resistor to 5.0 V provides bias current to the opto-coupler transistor. 15 DCL I Duty Cycle Limit An external resistor sets the maximum allowed duty cycle at OUT1 and OUT2. 16 RT/SYNC I Oscillator Adjust and Synchronizing input An external resistor sets the oscillator frequency. This pin also accepts ac-coupled synchronization pulses from an external source. 6 Specifications 6.1 Absolute Maximum Ratings (1) (2) MIN MAX UNIT VIN to GND –0.3 105 V VCC to GND –0.3 16 V RT/SYNC, RES and DCL to GND –0.3 5.5 V CS Pins to GND –0.3 1.25 V All other inputs to GND –0.3 7 V Junction temperature 150 °C Lead Temperature (Soldering 4 sec), (3) 260 °C 150 °C Storage temperature, Tstg (1) (2) (3) –55 Absolute Maximum Ratings are limits beyond which damage to the device may occur. Recommended Operating Conditions are conditions under which operation of the device is intended to be functional. For specifications and test conditions, see the Electrical Characteristics. If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and specifications. For detailed information on soldering plastic TSSOP packages, refer to the Packaging Data Book available from Texas Instruments. 6.2 ESD Ratings V(ESD) (1) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) VALUE UNIT ±2000 V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. 6.3 Recommended Operating Conditions over operating free-air temperature range (unless otherwise noted) VIN Voltage MIN MAX UNIT 13 100 V External Voltage Applied to VCC 8 15 V Operating Junction Temperature –40 125 °C 4 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 6.4 Thermal Information LM5032 THERMAL METRIC (1) PW UNIT 16 PINS RθJA Junction-to-ambient thermal resistance 96.8 RθJC(top) Junction-to-case (top) thermal resistance 30.3 RθJB Junction-to-board thermal resistance 42.4 ψJT Junction-to-top characterization parameter 1.7 ψJB Junction-to-board characterization parameter 41.8 (1) °C/W For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953. 6.5 Electrical Characteristics MIN and MAX limits apply –40°C ≤ TJ ≤ 125°C. VIN = 48 V, VCC = 10 V externally applied, RT = RDCL = 42.2kΩ, UVLO = 1.5 V, TJ = 25°C, unless otherwise stated, see (1)and see (2). SYMBOL PARAMETER TEST CONDITIONS MIN TYP MAX 8 UNIT STARTUP REGULATOR (VIN, VCC Pins) VCCReg VCC voltage Ext. supply disconnected. 7.4 7.7 ICC(Lim) VCC current limit VCC = 0V. 19 22 VCC UVT VCC Under-voltage threshold (VCC increasing) Ext. supply disconnected, VIN =11V. VCC decreasing V mA VCC VCC 300 mV 100 mV 5.5 V 6.2 6.9 V IIN Startup regulator current VIN = 90V, UVLO = 0V 500 600 µA ICCIn Supply current into VCC from external source Output loads = open, VCC = 10V 4.3 7 mA 1.22 1.25 1.28 V 16 20 24 µA 0.45 0.5 0.55 V UVLO UVLO Under-voltage threshold IHYST Hysteresis current CURRENT SENSE INPUT (CS1, CS2 Pins) CS Current Limit Threshold CS delay to output CS1 (CS2) taken from zero to 1.0V. Time for OUT1 (OUT2) to fall to 90% of VCC. Output load = 0 pF. Leading edge blanking time at CS1 (CS2) CS1 (CS2) sink impedance (clocked) RCS Internal pull-down FET on. 40 ns 50 ns 30 Equivalent input resistance at CS CS taken from 0.2V to 0.5V, internal FET off. 55 42 Ω kΩ CURRENT LIMIT RESTART (RES Pin) ResTh Threshold 2.4 2.55 2.7 V Charge source current 15 20 25 µA Discharge sink current 7.5 10 12.5 µA Current source (normal operation) 35 50 65 µA Current source during a current limit restart 0.7 1 1.3 µA SOFT-START (SS1, SS2 Pins) ISS VSS Open circuit voltage 5 V OSCILLATOR (RT/SYNC Pin) FS1 Frequency 1 (at OUT1, OUT2) RT = 42.2 kΩ 183 200 217 kHz FS2 Frequency 2 (at OUT1, OUT2) RT = 13.7 kΩ 530 600 670 kHz (1) (2) All electrical characteristics having room temperature limits are tested during production with TA = 25°C. All hot and cold limits are specified by correlating the electrical characteristics to process and temperature variations and applying statistical process control. Typical specifications represent the most likely parametric norm at 25°C operation Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 5 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Electrical Characteristics (continued) MIN and MAX limits apply –40°C ≤ TJ ≤ 125°C. VIN = 48 V, VCC = 10 V externally applied, RT = RDCL = 42.2kΩ, UVLO = 1.5 V, TJ = 25°C, unless otherwise stated, see(1)and see(2). SYMBOL PARAMETER TEST CONDITIONS MIN DC voltage TYP MAX 2 Input Sync threshold 2.6 3.3 UNIT V 3.7 V PWM CONTROLLER (COMP1, COMP2, Duty Cycle Limit Pins) Delay to output VCOMP COMP1 (COMP2) open circuit voltage ICOMP COMP1 (COMP2) short circuit current COMP1 (COMP2) set to 2V. CS1 (CS2) stepped from 0 to 0.4V. Time for OUT1 (OUT2) to fall to 90% of VCC. Output load = 0 pF. COMP1 (COMP2) = 0V 0.6 COMP1 (COMP2) to PWM1 (PWM2) gain 50 ns 5 V 1 1.4 0.33 Minimum duty cycle SS1 (SS2) = 0V Maximum duty cycle 1 UVLO pin = 1.30V, RDCL = RT, COMP1 (COMP2) = open 76% Maximum duty cycle 2 UVLO pin = 3.75V, RDCL = RT, COMP1 (COMP2) = open 20% Maximum duty cycle 3 UVLO pin = 1.30V, RDCL = RT/4, COMP1 (COMP2) = open 20% Maximum duty cycle 4 UVLO pin = 2.50V, RDCL = RT, COMP1 (COMP2) = open 50% Maximum duty cycle 5 UVLO pin = 1.30V, RDCL = RT/2, COMP1 (COMP2) = open 40% Slope compensation Delta increase at PWM comparator to CS1 (CS2) Channel mismatch CS1 (CS2) = 0.25V Soft-start to COMP offset SS1 (SS2) = 0.8V mA V/V 0% 90 mV 7% 0 V VCC0.2 V MAIN OUTPUT DRIVERS (OUT1, OUT2) Output high voltage IOUT = 50mA (source) VCC-1 Output low voltage IOUT = 100 mA (sink) 0.3 Rise time CLOAD = 1 nF 12 ns Fall time CLOAD = 1 nF 1 V 10 ns Peak source current 1.5 A Peak sink current 2.5 A 165 °C 20 °C THERMAL SHUTDOWN TSD Shutdown temperature Hysteresis 6 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 UVLO VIN UVT VCC tVCC 1.5V SS1 1.5V COMP1 t1 OUT1 SS2 COMP2 1.5V 1.5V OUT2 Figure 1. Startup Sequence Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 7 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com 6.6 Typical Characteristics 600 14 VCC Pin = Open 12 400 300 UVLO = 0V 200 VCC Pin = 10V 100 VCC pin = open, INPUT CURRENT IIN (mA) INPUT CURRENT IIN (PA) 500 OUT1 & OUT2 load = 2200 pF 10 8 Outputs frequency = 200 kHz UVLO > 1.25V 6 4 VCC pin = open, Driver Outputs Open 2 0 VCC pin = 10V, Driver Outputs open or loaded 0 0 20 40 60 80 100 0 20 VOLTAGE AT VIN (V) 40 60 80 100 VOLTAGE AT VIN (V) Figure 2. IIN vs VIN Figure 3. IIN vs VIN 100 8 7 Output Drivers @ 1 MHz 80 UVLO > 1.25V VCC Pin Unloaded 6 500 kHz 40 1 MHz 200 kHz 50 kHz 5 VCC (V) ICC (mA) 60 4 3 20 2 0 9 8 10 11 12 13 14 15 1 APPLIED VCC VOLTAGE (V) 0 OUT1, 2 = Open OUT1, 2 load = 2200 pF 2 0 4 6 8 10 12 14 VOLTAGE AT VIN (V) Figure 4. ICC vs Externally Applied VCC Figure 5. VCC vs VIN 10 OSCILLATOR FREQUENCY (MHz) 8 7 6 VCC (V) 5 4 3 2 1 0.1 0.01 0 0 5 10 15 20 1 25 10 100 1000 RT (k:) ICC (mA) Figure 6. VCC vs ICC (Externally Loaded) 8 1.0 Figure 7. Oscillator Frequency vs RT Resistor Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Typical Characteristics (continued) 100 80 80 MAXIMUM DUTY CYCLE (%) MAXIMUM DUTY CYCLE (%) 100 UVLO Pin = 1.26V 60 40 20 60 40 20 0 0 0 0.2 0.4 0.6 0.8 0 1.0 RDCL/RT Figure 8. User Defined Maximum Duty Cycle vs RDCL Resistor 5.0 Figure 9. Maximum Duty Cycle vs. UVLO Voltage 100 FREQUENCY @ OUT1, OUT2 (kHz) 210 R1 = 150 k: MAXIMUM DUTY CYCLE (%) 1.0 2.0 3.0 4.0 1.25V VOLTAGE AT UVLO PIN (V) R2 = 10 k: Figure 23 80 60 40 20 208 206 204 202 200 198 196 194 RT = 42.2k 192 190 0 0 20 40 60 -50 80 0 50 100 150 VOLTAGE AT VIN (V) TEMPERATURE (oC) Figure 10. Maximum Duty Cycle vs. VIN (Figure 24) Figure 11. Frequency vs. Temperature 510 55 45 | | 1.10 1.0 0.9 -50 CURRENT LIMIT THRESHOLD @ CS1, CS2 (mV) SOFT-START CURRENT (PA) 508 50 506 504 502 500 498 496 494 492 490 0 50 100 150 -50 TEMPERATURE (oC) 0 50 100 150 TEMPERATURE (oC) Figure 12. Soft-Start Pin Current vs Temperature Figure 13. Current Limit Threshold at CS1, CS2 vs Temperature Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 9 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com 7 Detailed Description 7.1 Overview The LM5032 contains all the features necessary to implement two independently regulated current mode dc/dc converters, or a single high current converter comprised of two parallel interleaved channels using the Forward converter topology. The two controllers operate 180° out of phase from a common oscillator, thereby reducing input ripple current. Each regulator channel contains a complete PWM controller, current sense input, soft-start circuit, and gate driver output. Common to both channels are the startup and VCC regulator, line under-voltage lockout, 2 MHz capable oscillator, maximum duty cycle control, and the hiccup mode fault protection circuit. The gate driver outputs (OUT1, OUT2) are designed to drive N-channel MOSFETs. Their compound configuration reduces the turn-off-time, thereby reducing switching losses. Additional features include thermal shutdown, slope compensation, and the oscillator synchronization capability. 10 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 7.2 Functional Block Diagram 7.7V SERIES REGULATOR VI N VCC VCC 6 VCC Disable THERMAL SHUTDOWN BIAS VOLTAGE GENERATOR RT/ SYNC VCC 5.0V VCC UVT CLK1, 2 UserMaxDC1, 2 OSCILLATOR & RAMP GENERATOR 20 PA UVLO SLOPE1, 2 DCL 5.0V MaxDC1 1.25V Ramp1 ILim1,2 20 PA RES UVLO Drivers Off RAMP1, 2 -VUVLO LOGIC Clk1,2 10 PA DC1,2 2.55V MaxDC2 R S Vref Q Ramp2 Restart Latch Q Support Functions Restart 5.0V 45 PA SLOPE1 VCC Drivers Off 5k PWM Comp 1 COMP1 10k CLK1 5k R Q S Q Driver Enable Current Limit 2k SS1 Driver Logic GND1 PWM1 MaxDC1 UserMaxDC1 CS1 OUT1 Restart PWM Latch DC1 CLK1 ILim1 OUT1+50 ns 42k 0.5V VCC UVT Controller 1 5.0V 45 PA SLOPE2 5k PWM Comp 2 COMP2 VCC PWM Latch 10k R Drivers Off Q PWM2 CLK2 S Current Limit 2k SS2 Driver Enable MaxDC2 UserMaxDC2 ILim2 5.0V Restart Latch GND2 DC2 CLK2 42k OUT2+50 ns VCC UVT SS1 1 PA Driver Logic Q 5k CS2 OUT2 Restart 0.5V Controller 2 Driver Enable 5.0V 5.0V 49 PA 49 PA Logic SS1 Restart 5.0V Latch 1 PA Logic SS2 SS2 Restart 1k Drivers Off Soft-start 1 1k Soft-start 2 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 11 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com 7.3 Feature Description 7.3.1 Line Undervoltage Lock Out, UVLO, Shutdown The LM5032 contains a line under-voltage lockout circuit (UVLO) designed to enable the VCC regulator and output drivers when the system voltage (VPWR) exceeds the desired level (see Figure 14). VPWR is the voltage normally applied to the transformer primary, and usually connected to the VIN pin (see the schematic on Page 1). The threshold at the UVLO comparator is 1.25V. An external resistor divider connected from VPWR to ground provides 1.25V at the UVLO pin when VPWR is increased to the desired turn-on threshold. When VPWR is below the threshold the VCC regulator and output drivers are disabled, and the internal 20 µA current source is off. When VPWR reaches the threshold, the comparator output switches low to enable the internal circuits and the 20 µA current source. The 20 µA flows into the external divider’s junction, raising the voltage at UVLO, thereby providing hysteresis. Internally the voltage at UVLO also drives the Maximum Duty Cycle Limiter circuit (described below), which may influence the values chosen for the UVLO pin resistors. At maximum VPWR, the voltage at UVLO should not exceed 6V. Refer to the Applications Information section for a procedure to calculate the resistors values. The LM5032 controller can be shutdown by forcing the UVLO pin below 1.25V with an external switch. When the UVLO pin is low, the outputs and the VCC regulator are disabled, and the LM5032 enters a low power mode. If VCC pin is not powered from an external source, the current into VIN drops to a nominal 500 µA. If the VCC pin is powered from an external source, the current into VIN is nominally 50 µA, and the current into the VCC pin is approximately 4.3 mA. To disable one regulator without affecting the other, see the description of the Soft-start section. VCC LM5032 7.6V/6.2V THERMAL SHUTDOWN VPWR VCC Disable 20 PA R1 UVLO Drivers Off UVLO 1.25V R2 Max . Duty Cycle Limiter Figure 14. Drivers Off and VCC Disable 7.3.2 Startup Regulator, VIN, VCC The high voltage startup regulator is integral to the LM5032. The input pin VIN can be connected directly to a voltage between 13V and 100V, with transient capability to 105V. The startup regulator provides bias voltages to the series pass VCC regulator and the UVLO circuit. The VCC regulator is disabled until the voltage at the UVLO pin (described above) exceeds 1.25V. For applications where VPWR exceeds 100V the internal startup regulator can be powered from an external startup regulator or other available low voltage source. See the Applications Information section for details. The VCC under-voltage threshold circuit (UVT) monitors the VCC regulator output. When the series pass regulator is enabled and the internal VCC voltage increases to > 7.6V, the UVT comparator activates the PWM controller and output drivers via the Drivers Off signal. The UVT comparator has built-in hysteresis, with the lower threshold nominally set to 6.2V. See Figure 1 and Figure 14. When enabled, the VCC regulated output is 7.7V ±4% with current limited to a minimum of 19 mA (typically 22 mA). The regulator’s output impedance is ≊ 6Ω. The VCC pin requires a capacitor to ground for stability, as well as to provide the surge currents to the external MOSFETs via the gate driver outputs. The capacitor should be physically close to the VCC and GND pins. In most applications it is necessary to power VCC from an external source as the average current required at the output drivers may exceed the current capability of the internal regulator and/or the thermal capability of the LM5032 package (see Figure 4). Normally the external source is derived from the converter’s power stage once the LM5032 outputs are active. Refer to the Applications Information section for more information. 12 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Feature Description (continued) 7.3.3 Drivers Off, VCC Disable Referring to Figure 14, Drivers Off and VCC Disable are internal signals which, when active disable portions of the LM5032. If the UVLO pin is below 1.25V, or if the thermal shutdown activates, the VCC Disable line switches high to disable the VCC regulator. UVLO also activates the Drivers Off signal to disable the output drivers, connect the SS1, SS2, COMP1, COMP2 and RES pins to ground, and enable the 50 µA Soft-start current sources. If the VCC voltage falls below the under-voltage threshold of 6.2V , the UVT comparator activates only the Drivers Off signal. The output drivers are disabled but the VCC regulator is not disabled. Additionally, the CS1, CS2, SS1, SS2, COMP1, COMP2 and RES pins are internally grounded, and the 50 µA Soft-start current sources are enabled. 7.3.4 Oscillator The oscillator frequency is set with an external resistor RT connected between the RT/SYNC and GND1 pins. The resistor value is calculated from: RT = 17100 FS - 0.001(FS - 400) (1) where FS is the desired oscillator frequency in kHz (maximum of 2 MHz), and RT is in kΩ. See Figure 7. The two gate driver outputs (OUT1 and OUT2) switch at half the oscillator frequency and 180° out of phase with each other. The voltage at the RT/SYNC pin is internally regulated at 2.0V. The RT resistor should be located as close as possible to the LM5032 with short direct connections to the pins. The LM5032 can be synchronized to an external clock by applying a narrow clock pulse to the RT/SYNC pin. See the Applications Information section for details on this procedure. The RT resistor is always required, whether the oscillator is free running or externally synchronized. 7.3.5 PWM Comparator/Slope Compensation The PWM comparator of each controller compares a slope compensated current ramp signal with the loop error voltage derived from the COMP pin. The COMP voltage is typically controlled by an external error amplifier/optocoupler feedback circuit to regulate the converter output voltage. Internally, the voltage at the COMP pin passes through two level shifting diodes and a gain reducing 3:1 resistor divider (see Figure 15). The compensated current ramp signal is a combination of the current waveform at the CS pin, and an internally generated ramp derived from the internal clock. At duty cycles greater than 50% current mode control circuits are prone to subharmonic oscillation. By adding a small fixed ramp to the external current sense signal oscillations can be avoided. The internal ramp has an amplitude of 45 µA and is sourced into an internal 2kΩ resistor, and a 42 kΩ resistor in parallel with the external impedance at the CS pin. The ramp current also flows through the external impedance connected to the CS pin and thus, the amount of slope compensation can be adjusted by varying the external circuit at the CS pin. The output of the PWM comparator provides the pulse width information to the output drivers. This comparator is optimized for speed in order to achieve minimum controllable duty cycles. The comparator’s output duty cycle is 0% for VCOMP ≤1.5V, and increases as VCOMP increases. If either Soft-start pin is pulled low (internally or externally) the corresponding COMP pin is pulled down with it, forcing the output duty cycle to zero. When the Soft-start pin voltage increases, the COMP pin is allowed to increase. An internal 5 kΩ resistor connected from COMP to an internal 5.0V supply provides a pull-up for the COMP pin and bias current to the collector of the opto-coupler transistor. Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 13 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Feature Description (continued) V PWR Current Sense Power Transformer V OUT Slope Comp. 45 PA Load LM5032 30 PWM Comparator LEB RF 2k CS1 CF 42k 10k 5k RCS V REF Error Amplifier COMP1 | 5.0V 5k Figure 15. Typical Feedback Network 7.3.6 Cycle-by-Cycle Current Limit Each CS pin is designed to accept a signal representative of its transformer primary current. If the voltage at CS exceeds 0.5V the current sense comparator terminates the present main output driver (OUT pin) pulse. If the high current fault persists, the controller operates with constant peak switch current in a cycle-by-cycle current limit mode, and a Hiccup Mode Current Limit Restart cycle begins (see below). Each CS pin is internally connect to ground through a 30Ω resistor during the main output off time to discharge external filter capacitance. The discharge device remains on for an additional 50 ns after the main output driver switches high to blank leading edge transients in the current sensing circuit. Discharging the CS pin filter each cycle and blanking leading edge spikes reduces the filter requirement which improves the current sense response time. The current sense comparators are fast and respond to short duration noise pulses. The external circuitry at each CS pin should include an R-C filter to suppress noise. Layout considerations are critical for the current sense filter and the sense resistor. Refer to the Applications Information section for PC board layout guidelines. 7.3.7 Hiccup Mode Current Limit Restart If cycle-by-cycle current limiting continues in either or both controllers for a sufficient period of time, the Current Limit Restart circuit disables both regulators and initiates a soft-start sequence after a programmable delay. The duration of cycle-by-cycle current limiting before turn-off occurs is programmed by the value of the external capacitor at the RES pin. The dwell time before output switching resumes is programmed by the value of the Soft-start capacitor(s). The circuit is detailed in Figure 16 and the timing is shown in Figure 17. A description of this circuit’s operation is as follows: a) No current limit detected: The 10 µA discharge current source at RES is enabled pulling the RES pin to ground. b) Current limit repeatedly detected at both CS inputs: The 20 µA current source at RES is enabled continuously to charge the RES pin capacitor as shown in Figure 17. The current limit comparators also terminate the PWM output pulses to provide a cycle-by-cycle current limiting. When the voltage on the RES capacitor reaches the 2.55V restart comparator threshold, the comparator sets the Restart Latch which produces the following restart sequence: • The SS1 and SS2 pin charging currents are reduced from 50µA to 1 µA. • An internal MOSFET is turned on to discharge the RES pin capacitor. • The internal MOSFETs at SS1 and SS2 are turned on to discharge the Soft-start capacitors. • COMP1 and COMP2 follow SS1 and SS2 respectively and reduce the PWM duty cycles to zero. • When the voltages at the SS pins fall below 200mV, the internal MOSFETs at the SS pins are turned off allowing the SS pins to be charged by the 1µA current sources. • When either SS pin reaches ≊1.5V its PWM controller produces the first pulse of a soft-start sequence which 14 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Feature Description (continued) resets the Restart Latch. The SS charging currents are increased to 50 µA and the soft-start sequence continues at the normal rate. If the overload condition still exists, the voltage at RES begins to increase again and repeat the restart cycle as shown in Figure 17. If the overload condition has been cleared, the RES pin is held at ground by the 10 µA current source. c) Current limit repeatedly detected at one of the two CS inputs: In this condition the RES pin capacitor is charged by the 20 µA current source once each clock cycle of the current limited regulator, and discharged by the 10 µA current source once each clock cycle of the unaffected regulator. The voltage at the RES pin increases one fourth as fast as in case b) described above. The current limited regulator operates in a cycle-by-cycle current limit mode until the voltage at RES reaches the 2.55V threshold. When the Restart Comparator output switches high the Restart Latch is set, both SS pin capacitors are discharged to disable the regulator channels, and a restart sequence begins as described in case b) above. To determine the value of the RES pin capacitor, see the Applications Information section. CS1 Current Limit Current Sense Circuit 5.0V Restart Current Source Logic 0.5V Clk1, Clk2 Current Limit Current Sense Circuit SS1 COMP1 DC1 PWM #1 To Output Drivers C RES 2.55V S Voltage Feedback 10 PA RES 0.5V CS2 Voltage Feedback 20 PA DC2 PWM #2 COMP2 Drivers Off SS2 1PA R Restart Comparator Q Restart Latch 49 PA SS1 SS1 SS C SS1 200 mV Logic 200 mV Logic Drivers Off Soft-start #1 1PA 49 PA SS2 SS2 SS C SS2 LM5032 Soft-start #2 Figure 16. Current Limit Restart Circuit Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 15 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Feature Description (continued) 2.55V Current Limit Detected at CS1 and/or CS2 RES 0V 5.0V SS1 and SS2 50 PA 1 PA #1.5V OUT1 OUT2 t1 t2 t3 Figure 17. Current Limit Restart Timing 7.3.8 Soft-Start Each soft-start circuit allows the corresponding regulator to gradually reach a steady state operating point, thereby reducing startup current surges and output overshoot. Upon turn-on, both SS pins are internally held at ground. When VCC increases past its under-voltage threshold (UVT), the SS pins are released and internal 50 µA current sources charge the external capacitors. The voltage at each COMP pin follows the SS pin, and when COMP reaches ≊1.5V, the output pulses commence at a low duty cycle. The voltage at the SS pins continues to increase and saturates at ≊5.0V, The voltage at each COMP pin increases to the value required for regulation where it is controlled by its voltage feedback loop (see Figure 1). If the internal Drivers Off line is activated (see Drivers Off, VCC Disable), both SS pins are internally grounded. The SS pins pull the COMP pins to ground while the Driver Off signal disables the output drivers. When the event which activated the Drivers Off line is cleared and Vcc exceeds its under-voltage threshold, the SS pins are released. The internal 50 µA current sources then charge the external soft-start capacitors allowing each regulator’s output duty cycle to increase. If the Current Limit Restart threshold is reached due to repeated over-current detections, both SS pins (and the COMP pins) are pulled to ground. The output drivers are disabled, and the 50 µA SS pin current sources are reduced to 1 µA. After a short propagation delay the SS pins and the COMP pins are released, and the external capacitors are charged up at a slow rate. When the COMP voltage reaches ≊ 1.5V, the output drivers are enabled, and the current sources at the SS pins are increased to 50 µA. The output duty cycle then increases to the value required for regulation. To shutdown one regulator without affecting the other, ground the appropriate SS pin. This forces the COMP pin to ground, reducing the output duty cycle to zero for that regulator. Releasing the SS pin allows normal operation to resume. 7.3.9 Output Duty Cycle The output driver’s duty cycle for each controller is normally controlled by comparing the voltage provided to the COMP input by the external voltage feedback circuit with the current information at the CS pin. However, the maximum duty cycle during transient or fault conditions may be intentionally limited by two other circuits, both of which are common to the two controller channels. User Defined Maximum Duty Cycle. The maximum allowed duty cycle can be set with the RDCL resistor connected from the DCL pin to GND1, according to the following equation: Maximum User Duty Cycle = 80% x RDCL/RT (2) RT is the oscillator frequency programming resistor connected to the RT/SYNC pin. The value of the RDCL resistor must be calculated after the RT resistor is selected. See Figure 8. Referring to the block diagram of the voltage at the DCL pin is compared to the Ramp1 and Ramp2 signals, creating the UserMaxDC1 and UserMaxDC2 timing signals. These signal are provided to the two 4-input AND gates to limit the PWM duty cycle of both channels. 16 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Feature Description (continued) Line Voltage Maximum Duty Cycle. The voltage at the UVLO pin, normally proportional to the voltage at VPWR, further limits the maximum duty cycle at high input voltages. Referring to Figure 10, when the UVLO pin is below 1.25V, the outputs are disabled. At UVLO = 1.25V the maximum allowed duty cycle is 80% (or less if limited by the DCL resistor). As the UVLO pin voltage increases with VPWR, the maximum duty cycle decreases, reaching a minimum of 10% at ≊4.5V. Referring to the UVLO voltage, after passing through an inverting gain stage, is compared to the Ramp1 and Ramp2 signals generated by the oscillator. The output of these comparators are the MaxDC1 and MaxDC2 timing signals. These signals are provided to the two 4-input AND gates which limit the PWM pulses delivered to the output drivers. Resulting Output Duty Cycle. The controller duty cycle is determined by the four signals into the 4-input AND gates in (UserMaxDC, MaxDC, PWM and CLK). The output driver pulsewidth is equal to the least of these four pulses. Whichever input of the AND gate transitions high-to-low first terminates the output driver’s on-time. 7.3.10 Driver Outputs OUT1, the primary switch driver for Controller 1 is designed to drive the gate of an N-channel MOSFET with 1.5A sourcing current and 2.5A sinking current. The peak output levels are VCC and GND1. The ground return path for Controller 1 is GND1. The corresponding pins for Controller 2 are OUT2 and GND2. OUT1 and OUT2 are compound gate drivers with CMOS and Bipolar output transistors as shown in Figure 18. The parallel MOS and Bipolar devices provide a faster turn-off of the primary switch thereby reducing switching losses. The outputs switch at one-half the oscillator frequency with the rising edges at OUT1 and OUT2 180° out of phase with each other. The on-time of OUT1 and OUT2 is determined by their respective duty cycle control. LM5032 VCC PWM OUT GND Figure 18. Compound Gate Driver 7.3.11 Thermal Shutdown The LM5032 should be operated so the junction temperature does not exceed 125°C. If a junction temperature transient reaches 165°C (typical), the Thermal Shutdown circuit activates the VCC Disable and Drivers Off lines (see Figure 14). The VCC regulator and the four output drivers are disabled, the SS1, SS2, and RES pins are grounded, and the soft-start current is set to 50 µA. This puts the LM5032 in a low power state helping to prevent catastrophic failures from accidental device overheating. When the junction temperature reduces below 145°C (typical hysteresis = 20°C), the VCC regulator is enabled and a startup sequence is initiated (Figure 1). 7.4 Device Functional Modes Normal device operating mode is described above in sections Line Undervoltage Lock Out, UVLO, Shutdown through Cycle-by-Cycle Current Limit, and sections Soft-Start to Thermal Shutdown. Under overcurrent fault conditions, the device operate in Hiccup Mode, as detailed above in the Hiccup Mode Current Limit Restart section. Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 17 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com 8 Application and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 8.1 Application Information 8.1.1 VIN The voltage applied to the VIN pin, normally the same as the system voltage applied to the power transformer’s primary (VPWR), can vary in the range of 13 to 100V with transient capability to 105V. The current into VIN depends primarily on the output driver capacitive loads, the switching frequency, and any external load at VCC. If the power dissipation associated with the VIN current exceeds the package capability, an external voltage should be applied to VCC (see Figure 2 & Figure 3) to reduce power in the internal start-up regulator. It is recommended the circuit of Figure 19 be used to suppress transients which may occur at the input supply, in particular where VIN is operated close to the maximum operating rating of the LM5032. When all internal bias currents for the LM5032 and output driver currents are supplied through VIN and the internal VCC regulator, the required input current (IIN) is shown in Figure 2 & Figure 3. In most applications, upon turn-on, IIN increases with VIN as shown in Figure 2 until the UVLO threshold is reached. After the outputs are enabled and the external VCC supply voltage is active, the current into VIN then drops to a nominal 120 µA. V PWR 50 VIN 0.1 PF LM5032 Figure 19. Input Transient Protection 8.1.2 For Applications > 100 V For applications where the system input voltage (VPWR) exceeds 100V, VIN can be powered from an external start-up regulator as shown in Figure 20, or from any other low voltage source as shown in Figure 21. Connecting VIN and VCC together allows the LM5032 to be operated with VIN below 13V. The voltage at VCC must not exceed 15V. The voltage source at the right side of Figure 20 is typically derived from the power stage, and becomes active once the LM5032’s outputs are active. VPWR 9V 0.1 VIN VCC C1 8V - 15V (from power stage) LM5032 Figure 20. Start-up Regulator for VPWR >100V 18 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Application Information (continued) 8V-15V Start-up Voltage VIN VCC 8V - 15V C1 LM5032 Figure 21. Bypassing the Internal Start-up Regulator 8.1.3 UVLO The under-voltage lockout threshold (UVLO) is internally set at 1.25V at the UVLO pin. With two external resistors as shown in Figure 22, the LM5032 is enabled when VPWR exceeds the programmed threshold voltage. When VPWR is above the threshold, the internal 20 µA current source is enabled to raise the voltage at the UVLO pin, providing hysteresis. R1 and R2 are determined from the following equations: R1 = VHYS/20 µA R2 = (3) 1.25 x R1 VPWR - 1.25 (4) where VHYS is the desired UVLO hysteresis at VPWR, and VPWR in the second equation is the turn-on voltage. For example, if the LM5032 is to be enabled when VPWR reaches 20V, and disabled when VPWR is decreased to 17V, R1 calculates to 150 kΩ, and R2 calculates to 10 kΩ. The voltage at UVLO should not exceed 6V at any time. V PWR LM5032 20 PA R1 UVLO Enable VCC Regulator and Output Drivers 1.25V R2 Max. Duty Cycle Limiter Figure 22. UVLO Circuit The LM5032 can be remotely shutdown by taking the UVLO pin below 1.25V with an external open collector or open drain device, as shown in Figure 23. The outputs, and the VCC regulator, are disabled, and the LM5032 enters a low power mode. To shut down one regulator without affecting the other, see the Soft-start section. V PWR LM5032 20 PA R1 UVLO 1.25V R2 Shutdown Control Max. Duty Cycle Limiter Figure 23. Shutdown Control Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 19 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Application Information (continued) 8.1.4 VCC The capacitor at VCC provides not only regulator noise filtering and stability, but also prevents VCC from dropping to the lower under-voltage threshold level (UVT = 6.2V) when the output drivers source current surges to the external MOSFET gates. Additionally, the capacitor provides a necessary time delay during startup. The time delay allows the internal circuitry of the LM5032 and associated external circuitry to stabilize before VCC reaches the upper UVT threshold level (7.6V), at which time the outputs are enabled and the soft-start sequence begins. VCC is nominally regulated at 7.7V. The delay to the UVT level (Figure 1) is calculated from the following: tVCC = C1 x 7.6V ICC(Lim) (5) where C1 is the capacitor at VCC and ICC(Lim) is the VCC regulator’s current limit. If the capacitor is 0.1 µF, the nominal ICC(Lim) of 22 mA provides a delay of approximately 35 µs. The capacitor value should range between 0.1 µF and 25 µF. Experimentation with the final design may be necessary to determine the optimum value for the VCC capacitor. The average VCC regulator current required to drive the external MOSFETs is a function of the MOSFET gate capacitance and the switching frequency (see Figure 4). To ensure VCC does not droop below the lower UVT threshold, an external supply should be diode connected to VCC to provide the required current, as shown in Figure 24. The applied VCC voltage must be between 8V and 15V. Providing the VCC voltage higher than the 7.7V regulation level with an external supply shuts off the internal regulator, reducing power dissipation within the IC. Internally there is a diode from the VCC regulator output to VIN. Typically the applied voltage is derived from an auxiliary winding on the power transformer, or on the output inductor. V PWR VIN VCC LM5032 8V - 15V (from external source) C1 GND1 GND2 Figure 24. External Power to VCC 8.1.5 Oscillator, Sync Input The oscillator frequency is generally selected in conjunction with the system magnetic components, and any other aspects of the system which may be affected by the frequency. The RT resistor at the RT/SYNC pin sets the frequency according to Equation 1. Each output (OUT1 and OUT2) switches at one-half the oscillator frequency. If the required frequency tolerance is critical in a particular application, the tolerance of the external resistor and the frequency tolerance specified in the Electrical Characteristics table must be considered when selecting the RT resistor. If the LM5032 is to be synchronized to an external clock, that signal must be coupled into the RT/SYNC pin through a 100 pF capacitor. The external synchronizing frequency must be at least 4% higher than the free running frequency set by the RT resistor and no higher than twice the free running frequency. The RT/SYNC pin voltage is nominally regulated at 2.0V and the external pulse amplitude should lift the pin to between 3.8V and 5.0V on the low-to-high transition. The synchronization pulse width should be between 15 and 150 ns. The RT resistor is always required, whether the oscillator is free running or externally synchronized. 8.1.6 Voltage Feedback, COMP1, COMP2 Each COMP pin is designed to accept a voltage feedback signal from the respective regulated output via an error amplifier and (typically) an opto-coupler. A typical configuration is shown in Figure 15. VOUT is compared to a reference by the error amplifier which has an appropriate frequency compensation network. The amplifier’s output drives the opto-coupler, which in turn drives the COMP pin. 20 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Application Information (continued) When the LM5032’s two controller channels are configured to provide a single high current output, COMP1 and COMP2 are typically connected together, and to the feedback signal from the optocoupler. 8.1.7 Current Sense, CS1, CS2 Each CS pin receives an input signal representative of its transformer’s primary current, either from a current sense transformer or from a resistor in series with the source of the primary switch, as shown in Figure 25 and Figure 26. In both cases the sensed current creates a ramping voltage across R1, and the RF/CF filter suppresses noise and transients. R1, RF and CF should be as physically close to the LM5032 as possible, and the ground connection from the current sense transformer, or R1, should be a dedicated track to the appropriate GND pin. The current sense components must provide >0.5V at the CS pin when an over-current condition exists. Power Current Sense VPWR VIN Transformer RF CS1 LM5032 CF R1 GND1 Q1 OUT1 Figure 25. Current Sense Using a Current Sense Transformer Power Transformer VPWR VIN Q1 OUT1 LM5032 RF CS1 CF R1 GND1 Figure 26. Current Sense Using a Source Sense Resistor (R1) 8.1.8 Hiccup Mode Current Limit Restart This circuit’s operation is described in the Functional Description. Also see Figure 16 and Figure 17. In the case of continuous current limit detection at both CS pins, the time required to reach the 2.55V RES pin threshold is: t1 = CRES x 2.55V 20 PA = 1.275 x 105 x CRES (6) For example, if CRES = 0.1 µF the time t1 in Figure 18 is approximately 12.75 ms. In the case of continuous current limit detection at one CS pin only, the time to reach the 2.55V threshold is increased by a factor of four, or: t1 = 5.1 x 105 x CRES (7) The time t2 in Figure 17 is set by the capacitor at each SS pin and the internal 1 µA current source, and is equal to: Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 21 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Application Information (continued) CSS x 1.5V t2 = 1 PA = 1.5 x 106 x CSS (8) If CSS = 0.1 µF t2 is ≊150 ms. Time t3 is set by the internal 50 µA current source, and is equal to: CSS x 3.5V t3 = 50 PA = 7 x 104 x CSS (9) The time t2 provides a periodic dwell time for the converter in the event of a sustained overload or short circuit. This results in lower average input current and lower power dissipated within the circuit components. It is recommended that the ratio of t2/(t1 + t3) be in the range of 5 to 10 to make good use of this feature. If the application requires no delay from the first detection of a current limit condition, so that t1 is effectively zero, the RES pin can be left open (no external capacitor). If it is desired to disable the hiccup mode current limit operation then the RES pin should be connected to ground. 8.1.9 Soft-Start The capacitors at SS1 and SS2 determine the time required for each regulator’s output duty cycle to increase from zero to its final value for regulation. The minimum acceptable time is dependent on the output capacitance and the response of each feedback loop to the COMP pin. If the Soft-start time is too quick, the output could significantly overshoot its intended voltage before the feedback loop has a chance to regulate the PWM controller. After power is applied and VCC has passed its upper UVT threshold (≊7.6V), the voltage at each SS pin ramps up as its external capacitor is charged up by an internal 50 µA current source (see Figure 1). The voltage at the COMP pins follow the SS pins. When both have reached ≊1.5V, PWM pulses appear at the driver outputs with very low duty cycle. The voltage at each SS pin continues to increase to ≊5.0V. The voltage at each COMP pin, and the PWM duty cycle, increase to the value required for regulation as determined by its feedback loop. The time t1 in Figure 1 is calculated from: CSS x 1.5V t1 = 50 PA = 3 x 104 x CSS (10) With a 0.1 µF capacitor at SS, t1 is ≊3 ms. If the Hiccup Mode Current Limit Restart circuit activates due to repeated current limit detections at CS1 and/or CS2, both SS1 and SS2 are internally grounded (see the section on Hiccup Mode Current Limit Restart). After a short propagation delay, the SS pins are released and the external SS pin capacitors are charged by internal 1 µA current sources. The slow charge rate provides a rest or dwell time for the converter power stage (t2 in Figure 17), reducing the average input current and component temperature rise while in an overload condition. When the voltage at the SS and COMP pins reach ≊1.5V, the first pulse out of either PWM comparator switches the internal SS pin current sources to 50 µA. The voltages at the SS and COMP pins then increase more quickly, increasing the duty cycle at the output drivers. The rest time t2 is the time required for SS to reach 1.5V: CSS x 1.5V t2 = 1 PA = 1.5 x 106 x CSS (11) With a 0.1 µF capacitor at SS, t2 is ≊150 ms. Experimentation with the startup sequence and over-current restart condition is usually necessary to determine the appropriate value for the SS capacitors. To shutdown one regulator without affecting the other, ground the appropriate SS pin with an open collector or open drain device as shown in Figure 27. The SS pin forces the COMP pin to ground which reduces the PWM duty cycle to zero for that regulator. Releasing the SS pin allows normal operation to resume. When the LM5032’s two controller channels are configured to provide a single high current output, SS1 and SS2 are typically connected together, requiring a single capacitor for the two pins. 22 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Application Information (continued) To Output Drivers LM5032 Opto Coupler COMP1 PWM Controller #1 SS1 Shutdown Control Softstart #1 C SS1 PWM Controller # 2 COMP2 Softstart #2 SS2 Opto Coupler CSS2 Figure 27. Shutting Down One Regulator Channel 8.1.10 Line Voltage Dependent Maximum Duty Cycle As VPWR increases and the voltage at UVLO follows, the maximum allowed duty cycle decreases according to the graph of Figure 9. Using values from the example above (R1 = 150 kΩ, R2 = 10 kΩ in Figure 22), the maximum duty cycle varies as shown in Figure 10. If it is desired to increase the slope of the ramp in Figure 10, Figure 28 shows a suggested configuration. After the LM5032 is enabled, Z1 clamps the voltage across R1B, and UVLO increases with VPWR at a rate determined by the ratio R2/(R1A + R2). V PWR R1A LM5032 20 PA R1B Z1 UVLO 1.25V R2 Max. Duty Cycle Limiter Figure 28. Altering the Slope of Duty Cycle vs. VPWR 8.1.11 User Defined Max Duty Cycle The maximum allowed duty cycle at OUT1 and OUT2 can be set with a resistor from DCL to GND1. See Figure 8 and Equation 2. The default maximum duty cycle (80%) determined by the internal clock signals can be selected by setting RDCL = RT. The oscillator frequency setting resistor (RT) must be determined before RDCL is selected. The DCL pin should not be left open. 8.2 Typical Application Figure 29 shows an example of an LM5032-controlled 200-W interleaved regulator which provides a single regulated 48-V output. The interleaving of two power stages to a single output reduces the ripple voltage across both input and output capacitors, and improves the power stage efficiency compared to a single-stage design. Since the two interleaved control blocks are used to regulate a single combined output, the two soft-start pins SS1 and SS2 are connected to a single soft-start capacitor, and the two COMP1 and COMP2 pins are connected together to a single error amplifier. Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 23 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com Typical Application (continued) Figure 29. Evaluation Module Schematic 8.2.1 Design Requirements DESIGN PARAMETERS VALUE Input voltage range, VIN 18 V to 45 V Output voltage, VOUT 48 V Output current, IOUT 4A Output ripple voltage, VRIPPLE(OUT) < 2% (960 mVpp) Switching frequency, FSW (per phase) 123 kHz 8.2.2 Detailed Design Procedure 8.2.2.1 Oscillator Frequency and Maximum Duty Cycle The LM5032 oscillator frequency should be set at twice the target switching frequency of each interleaved power stage, for example, Fosc = 2 x Fsw. From Equation 1, the required value of resistor on the RT pin (R9 in Figure 29) is calculated as follows: RT = 17100 17100 - 0.001´ (Fosc - 400) = - 0.001´ (246 - 400) = 69.67k W Fosc 246 (12) The nearest E96 value of 69.8 kΩ is used. The maximum duty cycle is set to 80% (see the Output Duty Cycle section) by choosing the same value resistor on the DCL pin, so R30 is also set to 69.8 kΩ. 8.2.2.2 Power Stage Design 8.2.2.2.1 Boost Inductor Selection Maximum and minimum operating duty cycles are calculated at maximum and minimum input voltage, where Vd is the boost diode forward voltage drop, and Vsw(on) is the voltage drop across the boost MOSFET plus current sense element: 24 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Dmax = Dmin = VOUT + Vd - VIN(MIN) VOUT + Vd - Vsw(on) VOUT + Vd - VIN(max) VOUT + Vd - Vsw(on) = 48 + 0.7 - 18 = 63.7% 48 + 0.7 - 0.5 (13) 48 + 0.7 - 45 = = 7.7% 48 + 0.7 - 0.5 (14) The highest average inductor current in each phase is calculated at highest load and minimum input voltage, where each phase is assumed to carry 50% of the total load current: L(avg) = 50% ´ Iout 0.5 ´ 4 = = 5.51A 1 - Dmax 1 - 0.637 (15) Allowing the peak-to-peak inductor current ripple to be 100% of the average: DIL(pk -pk) = IL(avg) = 5.51A (16) And the peak inductor current IL(peak) will be: IL(peak) = IL(avg) + DIL(pk -pk) 2 = 8.26A (17) Knowing the switching frequency, maximum duty cycle and target peak-peak ripple current, the required inductance can be calculated: Lmin = (VIN(min) - VSW(on) ´ Dmax fSW ´ DIL(pk -pk) = (18 - 0.5) ´ 0.637 = 16.4mH 123kHz ´ 5.51 (18) Off-the-shelf available inductors of 15 µH were used, resulting in slightly higher peak-peak inductor ripple current, and slightly higher inductor peak current. 8.2.2.2.2 Output Capacitor Selection The output ripple across the boost output capacitor can be approximated from the following equation, where COUT is the value of output capacitance, and ESR is the equivalent-series-resistance of the output capacitance. For this design, the chosen electrolytic output capacitors are 150 μF with 160-mΩ ESR, so the net capacitance is 300 μF and net ESR is 80 mΩ. é IOUT(max) ´ (1 - Dmin ) ù é 4 ´ (1 - 0.077) ù DVOUT = ê ú + ëéIL(peak) ´ ESR ûù = ê ú + [8.26 ´ 0.08] = 711mV ë 2 ´ 123k ´ 300m û ë 2 ´ fSW ´ COUT û (19) This meets the target 2% specification. However, the extra ceramic output capacitors will also absorb a significant percentage of the switching frequency ripple, so the resulting output peak-to-peak ripple voltage should be lower than the value calculated above, and should be comfortably less than the 2% specification. 8.2.2.2.3 Boost MOSFET Selection The boost MOSFET should be rated for at least the rated output voltage plus some margin for voltage ringing. A 60-V device was selected. Since the boost inductor value was chosen to achieve peak-to-peak ripple current equal to 100% of the average current, the RMS MOSFET current at maximum load and minimum Vin is: ISW(rms) = Dmax ´ DIL(pk -pk)2 + 3 ´ Ipeak 2 - 3 ´ Ipeak ´ DIL(pk -pk) = 3 0.637 ´ 5.512 + 3 ´ 8.262 - 3 ´ 8.26 ´ 5.51 = 4.57A 3 (20) The chosen 60-V rated MOSFET SUD50N06-9L has 9.3-mΩ Rds(on), resulting in approximately 200-mW conduction loss. 8.2.2.2.4 Boost Diode Selection The boost diode must have a reverse voltage rating of at least VOUT, plus some margin for ringing. Thus a 60-V rated part was selected. Since fast reverse recovery is important, a Schottky device can be used at this voltage rating. A common-cathode dual-diode MBR1560 was selected, with each diode connected to one or other of the interleaved phases. 8.2.2.3 UVLO Setting To ensure start-up below the required minimum system input voltage of 18 V, the UVLO divider resistors R6 and R8 are set to 17.4 kΩ and 2 kΩ, respectively. This sets the input UVLO turn-on level to: Vin(on) = R6 + R8 17.4 + 2 ´ VUVLO = ´ 1.25 = 12.125V R8 2 (21) Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 25 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com This gives plenty margin to the required 16-V minimum. Resistor R7 in series with the UVLO pin increases the effective UVLO hysteresis. 8.2.2.4 VIN, VCC, Startup To reduce the power dissipation in the internal startup regulator on the VIN pin, a separate external switching regulator is used. This consists of U2 (LM5009) plus associated circuitry C5, C6, R1, R2, C7, D1, L1, R3 and R4. This buck regulator is designed to generate a 10-V regulated supply voltage for the VCC of U1 LM5032. See the LM5009 device datasheet, SNVS402, for detailed design information. Since the LM5032 internal VIN regulator is not used in this design, the LM5032 VIN and VCC pins are shorted together. 8.2.2.5 Soft-Start and Overload Since the two soft-start pins SS1 and SS2 are connected to a single soft-start capacitor, C12, the combined charging current of both soft-start pins charges the single soft-start capacitor. The soft-start delay to commencement of first PWM switching can be calculated from: t ss _ delay = 1.5V ´ CSS 1.5 ´ 0.1mF = = 1.5ms 100mA 100mA (22) Thereafter, the soft-start ramp time will depend on the power stage design and the operating conditions (input voltage and output load). 8.2.2.6 Current Sense In order to improve the efficiency, a lower value current sense shunt resistance is used. To enable this lower value, the normal operating range of the CS1/CS2 pins is reduced by adding an external DC offset to the CS1/CS2 pins, as shown in Figure 30. U3 VREF 2.0V U1 R23 10k Q1 1k CS1 R10 R12-R16 0.022 Figure 30. Current Sense DC Offset Circuit This circuit uses the 2.048-V reference U3 to add a typical offset of 185 mV to both current-sense pins. This reduces the active range of the internal cycle-by-cycle current-limit comparator to 315 mV, allowing the currentsense shunt to be decreased to 66% of the value that would be otherwise required. From the power stage design calculations, the peak inductor current in each power stage was approximately 9 A at max load and minimum Vin. Allowing for tolerances, and providing some margin for output overload, the current-sense shunt resistors are chosen for a peak current limit of approximately 15 A: R12 / R13 = (0.5 - 0.185) V = 21mW 15A (23) A standard value of 20 mΩ was used. 8.2.3 Application Curves Figure 31 shows the measured efficiency as a function of load current and input voltage. 26 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 LM5032 www.ti.com SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 Figure 32 illustrates the switching nodes of the two interleaved phases, and the resulting output ripple at twice the switching frequency. This was measured at Vin of 24 V, where duty cycle is approx. 50% and maximum ripple-cancellation occurs. Figure 31. Efficiency vs. Load and Vin Figure 32. Output Ripple at 24-V Vin 9 Power Supply Recommendations The VCC pin requires a local decoupling capacitor to ground for stability of the internal regulator from the VIN pin. This decoupling capacitor also provides the current pulses to drive the gates of the external MOSFETs through the driver output pins. The decoupling capacitor should be placed close to the VCC and GND1/GNS2 pins, and should be tracked directly to the pins. The two ground pins (GND1 and GND2) must be connected together with a short direct connection. 10 Layout 10.1 Layout Guidelines The LM5032 Current Sense and PWM comparators are very fast, and respond to short duration noise pulses. The components at the CS, COMP, SS, DCL, UVLO, and the RT/SYNC pins should be as physically close as possible to the IC, thereby minimizing noise pickup in the PC board tracks. Layout considerations are critical for the current sense filter. If current sense transformers are used, both leads of each transformer secondary should be routed to the sense filter components and to the IC pins. The ground side of each transformer should be connected via a dedicated PC board track to its appropriate GND pin, rather than through the ground plane. If the current sense circuits employ sense resistors in the drive transistor sources, low inductance resistors should be used. In this case, all the noise sensitive low current ground tracks should be connected in common near the IC, and then a single connection made to the power ground (sense resistor ground point). The outputs of the LM5032 should have short direct paths to the power MOSFETs in order to minimize inductance in the PC board traces. The two ground pins (GND1, GND2) must be connected together with a short direct connection to avoid jitter due to relative ground bounce in the operation of the two regulators. If the internal dissipation of the LM5032 produces high junction temperatures during normal operation, the use of wide PC board traces can help conduct heat away from the IC. Judicious positioning of the PC board within the end product, along with use of any available air flow (forced or natural convection) can help reduce the junction temperatures. Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 27 LM5032 SNVS344B – MARCH 2005 – REVISED DECEMBER 2014 www.ti.com 10.2 Layout Example From EA2 From CS2 From VIN VIN From EA1 From CS1 COMP1 CS1 To GD1 RT/SYNC DCL COMP2 SS1 LM5032 CS2 UVLO SS2 VCC RES OUT1 OUT2 GND1 GND2 To GD2 Top-side copper Bottom-side copper Figure 33. Layout Example 11 Device and Documentation Support 11.1 Trademarks All trademarks are the property of their respective owners. 11.2 Electrostatic Discharge Caution These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 11.3 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 12 Mechanical, Packaging, and Orderable Information The following pages include mechanical, packaging, and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. 28 Submit Documentation Feedback Copyright © 2005–2014, Texas Instruments Incorporated Product Folder Links: LM5032 PACKAGE OPTION ADDENDUM www.ti.com 4-Nov-2014 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (°C) Device Marking (4/5) LM5032MTC/NOPB ACTIVE TSSOP PW 16 92 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM5032 MTC LM5032MTCX/NOPB ACTIVE TSSOP PW 16 2500 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM5032 MTC (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 4-Nov-2014 In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 6-Nov-2015 TAPE AND REEL INFORMATION *All dimensions are nominal Device LM5032MTCX/NOPB Package Package Pins Type Drawing TSSOP PW 16 SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 2500 330.0 12.4 Pack Materials-Page 1 6.95 B0 (mm) K0 (mm) P1 (mm) 5.6 1.6 8.0 W Pin1 (mm) Quadrant 12.0 Q1 PACKAGE MATERIALS INFORMATION www.ti.com 6-Nov-2015 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM5032MTCX/NOPB TSSOP PW 16 2500 367.0 367.0 35.0 Pack Materials-Page 2 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions. Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety-critical applications. In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and requirements. Nonetheless, such components are subject to these terms. No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties have executed a special agreement specifically governing such use. Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use. TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of non-designated products, TI will not be responsible for any failure to meet ISO/TS16949. Products Applications Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers DLP® Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps DSP dsp.ti.com Energy and Lighting www.ti.com/energy Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial Interface interface.ti.com Medical www.ti.com/medical Logic logic.ti.com Security www.ti.com/security Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video RFID www.ti-rfid.com OMAP Applications Processors www.ti.com/omap TI E2E Community e2e.ti.com Wireless Connectivity www.ti.com/wirelessconnectivity Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright © 2015, Texas Instruments Incorporated