DCR01 Series ® DCR 01 DCR 01 For most current data sheet and other product information, visit www.burr-brown.com Miniature, 1W Isolated REGULATED DC/DC CONVERTERS FEATURES APPLICATIONS ● UL1950 RECOGNIZED ● ● ● ● ● PDIP-18, SO-28(1) ● 53W/in3 (3.3W/cm3) POWER DENSITY ● DEVICE-TO-DEVICE SYNCHRONIZATION POINT-OF-USE POWER CONVERSION DIGITAL INTERFACE POWER GROUND LOOP ELIMINATION POWER-SUPPLY NOISE REDUCTION ● THERMAL PROTECTION ● 1000Vrms ISOLATION DESCRIPTION ● 400kHz SWITCHING DCR01 family is a series of high-efficiency, inputisolated, output-regulated DC/DC converters. In addition to 1W nominal, galvanically-isolated output power capability, this range of DC/DCs offer very low output noise, thermal protection and high accuracy. The DCR01 family is implemented in standard molded IC packaging, giving standard JEDEC outlines suitable for high-volume assembly. The DCR01 is manufactured using the same technology as standard IC packages, thereby achieving very high reliability. ● 125 FITS AT 55°C ● ±10% INPUT RANGE ● SHORT-CIRCUIT PROTECTED ● 5V, 12V, 24V INPUTS ● 3.3V, 5V OUTPUTS ● HIGH EFFICIENCY NOTE: (1) SO version available Q3 2000. VREC SYNC ENABLE VS Input Controller LDO Regulator ERROR VOUT 0V 0V International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132 © 2000 Burr-Brown Corporation PDS-1587A Printed in U.S.A. May, 2000 SPECIFICATIONS At TA = +25°C, VS = nominal, IO = 10mA, CO = 0.1µF, unless otherwise specified. DCR01 SERIES PARAMETER CONDITIONS OUTPUT Setpoint DCR010503 DCR010505 DCR011203(2) DCR011205(2) DCR012403(3) DCR012405(3) Setpoint Accuracy Maximum Output Current DCR010503 DCR010505 DCR011203(2) DCR011205(2) DCR012403(3) DCR012405(3) Output Short-Circuit Protected Line Regulation DCR010503 DCR010505 DCR011203(2) DCR011205(2) DCR012403(3) DCR012405(3) Over Line and Load DCR010503 DCR010505 DCR011203 DCR011205 DCR012403 DCR012405 Versus Temperature Ripple and Noise DCR0105 Ripple DCR0105 Noise INPUT Nominal Voltage (VS) Voltage Range Supply Current DCR010503 MIN TYP 3.3 5 3.3 5 3.3 5 0.5 DCR011203(2) DCR011205(2) DCR012403(3) DCR012405(3) Reflected Ripple Current DCR010503, DCR01505 Duration 2.0 V V V V V V % mA mA mA mA mA mA Infinite 1 1 1 1 1 1 10mA to 300mA Load, 4.5V to 10mA to 200mA Load, 4.5V to 10mA to 390mA Load, 10.8V to 10mA to 200mA Load, 10.8V to 10mA to 390mA Load, 21.6V to 10mA to 200mA Load, 21.6V to –40°C to +85°C 5.5V Line 5.5V Line 13.2V Line 13.2V Line 26.4V Line 26.4V Line 1.0 1.0 1.0 1.0 1.0 1.0 1.0 20MHz Bandwidth, 50% Load CIN = 2.2µF, CFILTER = 1µF, COUT = 0.1µF 100MHz Bandwidth, 50% Load CIN = 2.2µ, CFILTER = 1µF, COUT = 0.1µF DCR0105xx DCR0112xx DCR0124xx mV/V mV/V mV/V mV/V mV/V mV/V 2.5 2.5 2.5 2.5 2.5 2.5 % % % % % % % 5 mVp-p 35 mVp-p 5 12 24 V V V % +10 IO = 0mA IO = 10mA IO = 300mA IO = 0mA IO = 10mA IO = 200mA IO = 0mA IO = 10mA IO = 390mA IO = 0mA IO = 10mA IO = 200mA IO = 0mA IO = 10mA IO = 390mA IO = 0mA IO = 10mA IO = 200mA 18 28 335 25 40 310 13 17 173 13 18 125 15 17 94 15 17 71 mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA mA MHz Bandwidth, 100% Load CIN = 2.2µF, CFILTER = 1µF 8 mAp-p ® DCR01 UNITS 300 200 390 200 390 200 –10 DCR010505 MAX 2 SPECIFICATIONS (Cont.) At TA = +25°C, VS = nominal, IO = 10mA, CO = 0.1µF, unless otherwise specified. DCR01 SERIES PARAMETER ISOLATION Voltage CONDITIONS MIN 1s Flash Test 60s Test, UL1950(1) 1 1 Input/Output Capacitance TYP MAX kVrms kVrms pF 25 OUTPUT ENABLE CONTROL Logic High Input Voltage Logic High Input Current Logic Low Input Voltage Logic Low Input Current DCR010503 DCR010505 2.0 2.0 < VENABLE < VREC VREC 100 –0.2 0 < VENABLE < 0.5 ERROR FLAG Logic High Open Collector Leakage Logic Low Output Voltage 0.5 100 VERROR = 5V Sinking 2mA 10 0.4 THERMAL SHUTDOWN Junction Temperature Temperature Activated Temperature Deactivated 720 720 2.5 0 TEMPERATURE RANGE Operating –40 800 2.5 V nA V nA V V µA V °C °C 150 130 SYNCHRONIZATION PIN Max External Capacitance on SYNC Pin Internal Oscillator Frequency External Synchronization Frequency External Synchronization Signal High External Synchronization Signal Low UNITS 3 880 880 5.0 0.4 pF kHz kHz V V +85 °C NOTES: (1) During UL approval only. (2) DCR011203, DCR011205 available Q2 2000. (3) DCR0112403, DCR012405 available Q3 2000. ELECTROSTATIC DISCHARGE SENSITIVITY ABSOLUTE MAXIMUM RATINGS Input Voltage: DCR0105 ............................................................................................ 7V DCR0112 .......................................................................................... 15V DCR0124 .......................................................................................... 29V Storage Temperature ...................................................... –60°C to +125°C Lead Temperature (soldering, 10s) ................................................. 270°C This integrated circuit can be damaged by ESD. Burr-Brown recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ORDERING INFORMATION DCR01 Basic Model Number: 1W Product Voltage Input: 5V In Voltage Output: 5V Out Package Code: P = 18-Pin Plastic DIP, U = 28-Pin SO(1) 05 05 ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. (P) NOTE: (1) SO version available Q3 2000. The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems. ® 3 DCR01 PACKAGE/ORDERING INFORMATION PACKAGE PACKAGE DRAWING NUMBER SPECIFIED TEMPERATURE RANGE PACKAGE MARKING ORDERING NUMBER(1) TRANSPORT MEDIA DCR010503P PDIP-18 218-1 –40°C to +85°C DCR010503P DCR010503P Rails DCR010505P PDIP-18 218-1 –40°C to +85°C DCR010505P DCR010505P Rails SO-28 217-2 –40°C to +85°C DCR010503U DCR010503U/1K Tape and Reel DCR010505U(3) SO-28 217-2 –40°C to +85°C DCR010505U DCR010505U/1K Tape and Reel DCR011203P(2) PDIP-18 218-1 –40°C to +85°C DCR011203P DCR011203P Rails SO-28 217-2 –40°C to +85°C DCR011203U DCR011203U/1K Tape and Reel PRODUCT DCR010503U(3) DCR011203U(1, 3) DCR011205P(2) DCR011205U(1, 3) DCR012403P(3) DCR012403U(1, 3) DCR012405P(3) DCR012405U(1, 3) PDIP-18 218-1 –40°C to +85°C DCR011205P DCR011205P Rails SO-28 217-2 –40°C to +85°C DCR011205U DCR011205U/1K Tape and Reel PDIP-18 218-1 –40°C to +85°C DCR012403P DCR012403P Rails SO-28 217-2 –40°C to +85°C DCR012403U DCR012403U/1K Tape and Reel PDIP-18 218-1 –40°C to +85°C DCR012405P DCR012405P Rails SO-28 217-2 –40°C to +85°C DCR012405U DCR012405U/1K Tape and Reel NOTE: (1) Models with a slash (/) are available only in Tape and Reel in the quantities indicated (e.g., /1K indicates 1000 devices per reel). Ordering 1000 pieces of “DCR010503U/1K” will get a single 1000-piece Tape and Reel. (2) Available Q2 2000. (3) Available Q3 2000. PIN CONFIGURATIONS Top View SO PDIP VS 1 18 SYNC VS 1 28 SYNC NC 2 17 0VIN VS 2 27 0VIN NC 3 26 0VIN DCR01 DCR01U VREC 7 12 ERROR VREC 12 17 ERROR 0VOUT 8 11 ENABLE 0VOUT 13 16 ENABLE VO 9 10 DNC 15 DNC VO 14 PIN DEFINITION (PDIP) PIN DEFINITION (SO) PIN # PIN NAME DESCRIPTION PIN # PIN NAME 1 VS Voltage Input 1 VS Voltage Input 2 NC No Connection 2 VS Voltage Input 7 VREC Rectified Output 3 NC No Connection 8 0VOUT Output Ground 12 VREC Rectified Output Output Ground DESCRIPTION 9 VO Voltage Output 13 VOUT 10 DNC Do Not Connect 14 VO Voltage Output 11 ENABLE Output Voltage Enable 15 DNC Do Not Connect 12 ERROR 17 0VIN 18 SYNC Error Flag Active Low 16 ENABLE Input Ground 17 ERROR Synchronization Input 26 0VIN NOTE: (1) SO version available Q3 2000. ® DCR01 4 27 0VIN 28 SYNC Output Voltage Enable Error Flag Active Low Input Ground Input Ground Synchronization Input TYPICAL PERFORMANCE CURVES At TA = +25°C, VS = 5V, IO = 10mA, CO = 0.1µF, unless otherwise specified. DCR0105 OUTPUT NOISE (100MHz Bandwidth) 80 12 70 60 10 Noise (mVp-p) Ripple Voltage (mVp-p) DCR0105 OUTPUT VOLTAGE RIPPLE 14 8 6 4 40 30 20 2 10 0 0 0 20 40 60 80 0 100 20 40 60 80 Load (%) Load (%) DCR010503P EFFICIENCY (VIN = 5V) DCR010503P VOUT vs LOAD (VIN = 5V) 100 3.305 70 85°C 85°C 3.3 60 3.295 50 VOUT (V) –40°C 40 25°C 30 20 3.29 3.285 25°C 3.28 3.275 10 3.27 0 3.265 –40°C 10 20 30 40 50 60 70 80 90 0 100 10 20 30 40 50 60 70 Load (%) Load (%) DCR0105 SERIES INPUT CURRENT REFLECTED NOISE (100MHz Bandwidth) DCR0105 SERIES INPUT CURRENT REFLECTED RIPPLE 80 90 100 20mA/div 0 40mA/div Efficiency (%) 50 500ns/div 500ns/div ® 5 DCR01 TYPICAL PERFORMANCE CURVES (Cont.) At TA = +25°C, VS = 5V, IO = 10mA, CO = 0.1µF, unless otherwise specified. DCR010503P LOAD TRANSIENT RESPONSE DCR010503P LOAD TRANSIENT RESPONSE 150mA Changing to 300mA 30mA Changing to 325mA Load Current Load Current 200mV/div 200mV/div Output Voltage Output Voltage 10µs/div 10µs/div DCR010503P OUTPUT VOLTAGE NOISE AT 100% LOAD (100MHz Bandwidth) DCR010503P OUTPUT VOLTAGE RIPPLE AT 100% LOAD (20MHz Bandwidth) 5mV/div 20mV/div Load Current Output Voltage 200ns/div 200ns/div DCR010505P LOAD TRANSIENT RESPONSE DCR010505P LOAD TRANSIENT RESPONSE 100mA Changing to 200mA 200mV/div 200mV/div 20mA Changing to 200mA Load Current Output Voltage 10µs/div Output Voltage 10µs/div ® DCR01 Load Current 6 TYPICAL PERFORMANCE CURVES (Cont.) At TA = +25°C, VS = 5V, IO = 10mA, CO = 0.1µF, unless otherwise specified. DCR010505P OUTPUT VOLTAGE NOISE AT 100% LOAD (100MHz Bandwidth) 5mV/div 20mV/div DCR010505P OUTPUT VOLTAGE RIPPLE AT 100% LOAD (20MHz Bandwidth) 200ns/div 200ns/div The DCR01 overcomes this by allowing devices to be synchronized to one another. Up to eight devices can be synchronized by connecting the SYNC pins together, with care being taken to minimize the capacitance of tracking. Significant stray capacitance on the SYNC pin will have the effect of reducing the frequency of the internal oscillator. If this is large, the DCR01 may be taken out with its optimized operating parameters and saturation of the magnetics may result, damaging the device. If devices are synchronized, it should be noted that all devices will draw maximum current simultaneously at start up. This can cause the input voltage to dip. Should it fall below the minimum input voltage, the devices may not start up. A 2.2µF capacitor (low ESR) should be connected as close to the device input pins as possible for the 5V input devices and a 0.47µF capacitor for the 12V and 24V devices. If more than eight devices are required to be synchronized, it is recommended that external synchronization be used. Details are contained in Burr-Brown’s Application Bulletin AB-153. FUNCTIONAL DESCRIPTION OVERVIEW The DCR01 series offers isolation from an unregulated power supply operating from a choice of input voltages. The DCR01’s provide a variety of regulated output voltages at a nominal output power of 1W or above. POWER STAGE The input supply is chopped at a frequency of 400kHz (internal oscillator divided by 2), which is used to drive the center-tapped toroidal transformer. RECTIFICATION The transformer’s output is full wave rectified and smoothed by the external capacitor connected to VREC. REGULATOR The internal low drop-out regulator provides a well-regulated output voltage, throughout the operating range of the device. CONSTRUCTION The DCR01 is manufactured using the same technology as standard IC packages. There is no substrate within the package. The DCR01 is constructed using a driver IC, Low Dropout Voltage Regulator, rectifier diodes and a wound magnetic toroid, all mounted on a leadframe. The DCR01 requires no special PCB assembly processing, as there is no solder within the package. The result is an isolated DC/DC converter with inherently high reliability. OSCILLATOR AND WATCHDOG The DCR01 uses an internal saw-tooth generator to provide the 800kHz on-board oscillator that is used to drive the power switching circuit. The operation of the oscillator is monitored by the watchdog, which will tri-state the output driver circuit if the oscillator fails, or if the SYNC pin is taken low, (shutdown mode). When the SYNC pin is returned high, normal operation resumes. ADDITIONAL FUNCTIONS SYNCHRONIZATION DISABLE/ENABLE If more than one DCR01 is being used, beat frequencies and other electrical interference can be generated. This is due to the small variations in switching frequencies between the converters. The DCR01 can be disabled or enabled by driving the SYNC pin using an open drain CMOS gate. If the SYNC pin is ® 7 DCR01 It is recommended that a 0.1µF low ESR capacitor is connected close to the output pin and ground to reduce noise on the output. The capacitor values listed are minimum values. If lower ripple is required then the filter capacitor should be increased in value to 0.47µF. NOTE: As with all switching power supplies the best performance is only obtained with low ESR capacitors connected close to the switcher. If low ESR capacitors are not used, the ESR will generate a voltage drop when the capacitor is supplying the load power. Often a larger capacitor is chosen for this purpose when a low ESR smaller capacitance would perform as well. pulled low, the DCR01 will be disabled. The disable time depends upon the external loading. The internal disable function is implemented in 2µs. Removal of the pull down will enable the DCR01. Capacitance loading on the SYNC pin should be minimized in order to prevent a reduction in the internal oscillator‘s frequency. See Application Bulletin AB-153 External Synchronization of the DCP01/02 Series of DC/DC Converters. This document contains information on how to null the effects of additional capacitance on the sync pin. The oscillators frequency can be measured at VREC, as this is the fundamental frequency of the ripple component. PCB LAYOUT OUTPUT ENABLE/DISABLE RIPPLE AND NOISE The regulated output of the DCR01 can be disabled by pulling the ENABLE pin low. Holding the ENABLE pin high enables the regulated output voltage, thus allowing the output to be controlled from the isolated side. Careful consideration should be given to the layout of the PCB in order for the best results to be obtained. The DCR01 is a switching power supply and as such can place high peak current demands on the input supply. In order to avoid the supply falling momentarily during the fast switching pulses, ground and power planes should be used to track the power to the input of DCR01, this will also serve to reduce noise on the circuit. If this is not possible, the supplies must be connected in a star formation, with the tracks made as wide as possible. If the SYNC pin is being used, the tracking between device SYNC pins should be short to avoid stray capacitance. If the SYNC pin is not being used it is advisable to place a guard ring (connected to input ground) around this pin to avoid any noise pick up. The output should be taken from the device using ground and power planes. This will ensure minimum losses. A good quality low ESR capacitor placed as close as practicable across the input will reduce reflected ripple and ensure a smooth start up. A good quality low ESR capacitor placed as close as practicable across the rectifier output terminal and output ground will give the best ripple and noise performance. ERROR FLAG The DCR01 has an Error pin which provides a ‘power good’ flag, as long as the internal regulator is in regulation. DECOUPLING Ripple Reduction Due to the very low forward resistance of the DMOS switching transistors, high current demands are placed upon the input supply for a short time. By using a good quality low Equivalent Series Resistance (ESR) capacitor of 2.2µF (minimum) for the 5V input devices and a 0.47µF capacitor for the 12V and 24V devices, placed close to the IC supply input pins, the effects on the power supply can be minimized. The high switching frequency of 400kHz allows relatively small values of capacitors to be used for filtering the rectified output voltage. A good quality low ESR capacitor of 1µF placed close to the VREC pin and output ground will reduce the ripple. It is not recommended that the DCR01 be fitted using an IC socket as this will degrade performance. The output at VREC is full wave rectified and produces a ripple of 800kHz. THERMAL MANAGEMENT Due to the high power density of this device, it is advisable to provide a ground plane on the output. The output regulator is mounted on a copper leadframe, and a ground plane will serve as an efficient heatsink. ® DCR01 8 VIN VS CIN(1) VOUT DCR COUT = 0.1µF 01 VREC 0V VO1 0V 0 VOUT CFILTER = 1µF NOTE: (1) 2.2µF capacitor with low ESR for 5V devices and 0.47µF for 12V and 24V devices. FIGURE 1. DCR01 with a Single Output. VIN VS CIN(1) SYNC VOUT DCR COUT = 0.1µF 01 VREC 0V VO1 0V 0 VOUT CFILTER = 1µF 0 VOUT VIN VS CIN(1) SYNC VOUT DCR COUT = 0.1µF 01 VREC 0V VO2 0V 0 VOUT CFILTER = 1µF 0 VOUT NOTE: (1) 2.2µF capacitor with low ESR for 5V devices and 0.47µF for 12V and 24V devices. FIGURE 2. Self-Synchronizing DCR01s with a Dual Output. ® 9 DCR01