Digital Controller for Isolated Power Supply Applications ADP1043 Preliminary Technical Data FEATURES PRODUCT OVERVIEW Integrates all typical controller functions Digital control loop Remote and local voltage sense Primary and secondary side current sense PWM control Synchronous rectifier control Hot-swap sense and control Current sharing Integrated programmable loop filter I2C interface Extensive fault detection and protection Extensive programming Fast calibration 8 Kb EEPROM Standalone or microcontroller control The ADP1043 is a secondary side power supply controller IC that is designed to provide all the functions that are typically needed in an isolated ac/dc or dc/dc control application. APPLICATIONS A comprehensive GUI is provided for easy design of loop filter characteristics and programming of the safety features. The industry-standard I2C bus gives access to the many monitoring and system test functions. The ADP1043 is optimized for minimal component count, maximum flexibility, and minimum design time. Features include remote voltage sense, local voltage sense, primary and secondary side current sense, PWM generation, and hot-swap sense and control. The control loop is digital, with an integrated programmable digital filter. Protection features include current limiting, ac sense, UVLO, and OVP (overvoltage protection). The built-in EEPROM provides extensive programming of the integrated loop filter, PWM signal timing, inrush current, soft start timing and sequencing. Reliability is improved through a built-in checksum and redundancy of critical circuits. AC/DC power supplies Isolated dc/dc power supplies Redundant power supplies Parallel power supplies Server, storage, network, and communications infrastructure The ADP1043 is available in a 32-lead LFCSP package and operates from a single 3.3 V supply. PFC AC INPUT LOAD DRIVER SR1 SR2 DRIVER ACSNS CS2+ CS2– PGND VS1 GATE VS2 CS1 DRIVER ADuM1400 OUTA OUTB ADP1043 OUTC OUTD OUTAUX RES ADD RTD VCORE FLAGIN PSON PGOOD2 PGOOD1 SDA SCL VS3+ VS3– SHAREo SHAREi VDD DGND AGND MICROCONTROLLER 07182-001 VDD Figure 1. Typical Application Circuit Rev. PrA 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 rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved. ADP1043 Preliminary Technical Data GENERAL DESCRIPTION The ADP1043 is a secondary side controller for switch mode power supplies (SMPS). It is designed for use in isolated redundant applications. The ADP1043 integrates the typical functions that are needed to control a power supply. These include Conventional power supply housekeeping features, such as remote and local voltage sense and primary and secondary side current sense, are included. An extensive set of protections is offered, including overvoltage protection (OVP), overcurrent protection (OCP), overtemperature protection (OTP), undervoltage protection (UVP), ground continuity monitoring, and ac sensing. Output voltage sense and feedback Digital loop filter compensation PWM generation Current sharing OrFET control Current, voltage, and temperature sense Housekeeping and I2C interface Calibration and trimming All these features are programmable through the I2C bus interface. This bus interface is also used to calibrate the power supply. Other information, such as input current, output current, and fault flags, is also available through the digital bus interface. The internal 1024-byte EEPROM makes it possible to store all programmed values and allows standalone control without a microcontroller. Approximately 700 bytes of the EEPROM are available for user information, such as version and manufacturing date. The ADP1043 comes with a free downloadable GUI, which provides all the necessary software to program the part. GATE VS1 PGND The ADP1043 operates from a single 3.3 V supply and is specified from −40°C to +85°C. ACSNS CS2+ CS2– The main function of controlling the output voltage is performed using the feedback ADCs, the digital loop filter, and the PWM block. The feedback ADCs use a patented multipath approach. There is a combination of a high speed, low resolution (fast and coarse) ADC and a low speed, high resolution (slow and accurate) ADC. Loop compensation is implemented using the digital filter. This PID (proportional, integral, derivative) filter is implemented in the digital domain, allowing easy programming of filter characteristics, which is of great value in customizing and debugging designs. The PWM block generates up to six programmable PWM outputs for control of FET drivers and synchronous rectification FET drivers. This programmability allows many traditional and unique switching topologies to be realized. VS2 ADP1043 VREF OSC ADC CS1 ADC ADC ADC ADC ADC SR1 SR2 PWM PWM ENGINE DIGITAL CORE OUTC OUTD OUTAUX VDD UVLO ADC LDO VCORE RES VS3– SHAREo OUTA OUTB VS3+ SHAREi 8kB EEPROM PGOOD1 I2C INTERFACE PGOOD2 ADC FLAGIN PSON IREF SCL AGND SDA DGND ADD RTD Figure 2. Functional Block Diagram Rev. PrA | Page 2 of 8 07182-002 • • • • • • • • A current share bus interface is provided for parallel power supplies. The part also has hot-swap OrFET sense and control for N+1 redundant power supplies. Preliminary Technical Data ADP1043 32 31 30 29 28 27 26 25 VS3+ VS3– RES ADD RTD VDD VCORE DGND PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 1 2 3 4 5 6 7 8 PIN 1 INDICATOR ADP1043 TOP VIEW (Not to Scale) 24 23 22 21 20 19 18 17 SHAREi SHAREo PGOOD1 PGOOD2 FLAGIN PSON SDA SCL 07182-003 SR1 SR2 OUTA OUTB OUTC OUTD OUTAUX GATE 9 10 11 12 13 14 15 16 VS2 AGND VS1 CS2– CS2+ ACSNS CS1 PGND Figure 3. Pin Configuration Table 1. Pin Function Descriptions Pin No. 1 Mnemonic VS2 2 AGND 3 VS1 4 CS2− 5 CS2+ 6 ACSNS 7 CS1 8 PGND 9 SR1 10 SR2 11 OUTA 12 OUTB 13 OUTC 14 OUTD 15 OUTAUX 16 GATE Description Power Supply Output Sense Input. This signal is referred to PGND. Input to a low frequency Σ-Δ ADC. Nominal voltage at this pin should be 1 V. Analog Ground. This pin is the ground for the analog circuitry of the ADP1043. Star connect to DGND. Local Voltage Sense Input. This signal is referred to PGND. Input to a high frequency Σ-Δ ADC. Nominal voltage at this pin should be 1 V. Inverting Differential Current Sense Input. Nominal voltage at this pin should be 1 V for best operation. When using high-side current sense in a 12 V application, a 110 kΩ resistor should be placed between the sense resistor and this pin. When using low-side current sense, a 10 kΩ resistor should be placed between the sense resistor and this pin. When using high-side, use the formula R = (VCOMMONMODE − 1)/100 μA. Noninverting Differential Current Sense Input. Nominal voltage at this pin should be 1 V for best operation. When using high-side current sense in a 12 V application, a 110 kΩ resistor should be placed between the sense resistor and this pin. When using low-side current sense, a 10 kΩ resistor should be placed between the sense resistor and this pin. When using high-side, use the formula R = (VCOMMONMODE − 1)/100 μA. AC Sense Input. This input is connected upstream of the main inductor through a resistor divider network. The nominal voltage at this pin should be 1 V. This signal is referred to PGND. Primary Side Differential Current Sense Input. This is the current transformer input to measure and control the primary side current. This signal is referred to PGND. Power Ground. This pin is the ground connection for the main power rail of the power supply. Star connect to AGND. Synchronous Rectifier Output. This PWM output is connected to the input of a FET driver. This pin can be disabled when not in use. This signal is referred to AGND. Synchronous Rectifier Output. This PWM output is connected to the input of a FET driver. This pin can be disabled when not in use. This signal is referred to AGND. PWM Output for Primary Side Switch. This pin can be disabled when not in use. This signal is referred to AGND. PWM Output for Primary Side Switch. This pin can be disabled when not in use. This signal is referred to AGND. PWM Output for Primary Side Switch. This pin can be disabled when not in use. This signal is referred to AGND. PWM Output for Primary Side Switch. This pin can be disabled when not in use. This signal is referred to AGND. Auxiliary PWM Output. This pin can be disabled when not in use. This signal is referred to AGND. OrFET Gate Drive Output. This output is open drain. This signal is referred to AGND. Rev. PrA | Page 3 of 8 ADP1043 Preliminary Technical Data Pin No. 17 18 19 20 21 Mnemonic SCL SDA PSON FLAGIN PGOOD2 22 PGOOD1 23 SHAREo 24 SHAREi 25 DGND 26 27 28 VCORE VDD RTD 29 ADD 30 RES 31 32 VS3− VS3+ Description I2C Serial Clock Input. This signal is referred to AGND. I2C Serial Data Input and Output (Open Drain). This signal is referred to AGND. Power Supply On Input. This signal is referred to DGND. Flag Input. An external signal can be input here to generate a flag condition. Power-Good Output (Open Drain). This signal is referred to AGND. This pin is controlled by the PGOOD2 flag. If any flag is set, this pin toggles. Power-Good Output (Open Drain). This signal is referred to AGND. This pin is controlled by the PGOOD flag. If any of the following are out of range, this pin toggles: ACSNS, OCP CS1, OCP CS2, VS1 OVP, VS2 OVP, or UVP. Share Bus Output Voltage Pin. When configured as a digital share bus, this pin is a digital output. When configured as an analog share bus, this pin is an open-drain analog output. This signal is referred to VS3−. Analog Share Bus Feedback Pin. This signal is input to an ADC in the ADP1043. This signal is referred to VS3−. Digital Ground. This pin is the ground for the digital circuitry of the ADP1043. Star connect to AGND. Output of 2.5 V Regulator. Connect a 100 nF capacitor from this point to DGND. Positive Supply Input. Range is from 3 V to 3.6 V. This signal is referred to AGND. Thermistor Input. A 10 kΩ or 100 kΩ thermistor is placed from this pin to AGND. This signal is referred to AGND. Address Select Input. Connect a resistor from ADD to GND. This signal is referred to AGND. Resistor Input. This pin sets up the internal voltage reference for the ADP1043. Connect a 50 kΩ resistor (±1%) from RES to GND. This signal is referred to AGND. Decoupling this pin to AGND is recommended for noise immunity. Inverting Remote Voltage Sense Input. There should be a low ohmic contact to AGND. Noninverting Remote Voltage Sense Input. This signal is referred to VS3−. Rev. PrA | Page 4 of 8 Preliminary Technical Data ADP1043 OUTLINE DIMENSIONS 0.60 MAX 5.00 BSC SQ 0.60 MAX 25 24 PIN 1 INDICATOR TOP VIEW 0.50 BSC 4.75 BSC SQ 0.50 0.40 0.30 12° MAX 1.00 0.85 0.80 PIN 1 INDICATOR 32 17 16 9 8 0.25 MIN 3.50 REF 0.80 MAX 0.65 TYP 0.30 0.23 0.18 3.25 3.10 SQ 2.95 EXPOSED PAD (BOTTOM VIEW) 0.05 MAX 0.02 NOM SEATING PLANE 1 0.20 REF COPLANARITY 0.08 COMPLIANT TO JEDEC STANDARDS MO-220-VHHD-2 Figure 4. Mechanical Package Dimensions Rev. PrA | Page 5 of 8 ADP1043 Preliminary Technical Data NOTES Rev. PrA | Page 6 of 8 Preliminary Technical Data ADP1043 NOTES Rev. PrA | Page 7 of 8 ADP1043 Preliminary Technical Data NOTES ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. PR07182-0-2/08(PrA) Rev. PrA | Page 8 of 8