DCP02 Series DC P0 2 DC P0 2 www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 Miniature, 2W, Isolated UNREGULATED DC/DC CONVERTERS FEATURES DESCRIPTION 1 • • • • • • • 2 Up To 89% Efficiency Thermal Protection Device-to-Device Synchronization SO-28 Power Density of 106W/in3 (6.5W/cm3 ) EN55022 Class B EMC Performance UL1950 Recognized Component JEDEC 14-Pin and SO-28 Packages APPLICATIONS • • • • • Point-of-Use Power Conversion Ground Loop Elimination Data Acquisition Industrial Control and Instrumentation Test Equipment 800kHz Oscillator SYNC/DISABLE The DCP02 series is a family of 2W, isolated, unregulated DC/DC converters. Requiring a minimum of external components and including on-chip device protection, the DCP02 series provides extra features such as output disable and synchronization of switching frequencies. The use of a highly integrated package design results in highly reliable products with power densities of 79W/in3 (4.8W/cm3) for DIP-14, and 106W/in3 (6.5W/cm3) for SO-28. This combination of features and small size makes the DCP02 suitable for a wide range of applications. Divide-by-2 Reset VOUT Power Stage 0V Watchdog/ Startup PSU Thermal Shutdown IBIAS VS Power Controller IC 0V 1 2 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. All trademarks are the property of their respective owners. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2000–2008, Texas Instruments Incorporated DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. 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. ORDERING INFORMATION For the most current package and ordering information, see the Package Option Addendum at the end of this data sheet, or see the TI website at www.ti.com. Supplemental Ordering Information DCP02 05 05 (D) ( ) Basic Model Number: 2W Product Voltage Input: 5V In Voltage Output: 5V Out Dual Output: Package Code: P = DIP-14 U = SO-28 ABSOLUTE MAXIMUM RATINGS Over operating free-air temperature range (unless otherwise noted) (1) PARAMETER Input Voltage DCP02 Series UNIT 5V input models 7 V 12V input models 15 V 15V input models 18 V 24V input models 29 V –60 to +125 °C Storage temperature range (1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS At TA = +25°C, unless otherwise noted. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT OUTPUT Power 100% full load Ripple Output capacitor = 1µF, 50% load Voltage vs. Temperature 2 W 20 mVPP Room to cold 0.046 %/°C Room to hot 0.016 %/°C INPUT Voltage range on VS –10 10 % ISOLATION Voltage 1s Flash test 1 kVrms 60s test, UL1950 (1) 1 kVrms LINE REGULATION Output Voltage (1) (2) 2 IO = constant (2) VS (min) to VS (typ) 1 15 % VS (typ) to VS (max) 1 15 % During UL1950 recognition tests only. IOUT ≥ 10% load current Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 ELECTRICAL CHARACTERISTICS (continued) At TA = +25°C, unless otherwise noted. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT SWITCHING/SYNCHRONIZATION Oscillator frequency (fOSC) Switching frequency = fOSC/2 800 Sync input low 0 Sync input current kHz 0.4 VSYNC = +2V V µA 75 Disable time µs 2 Capacitance loading on SYNC pin 3 (3) External pF RELIABILITY Demonstrated TA = +55°C 75 FITS THERMAL SHUTDOWN IC temperature at shutdown +150 °C 3 mA Shutdown current TEMPERATURE RANGE Operating (3) –40 °C +85 For more information, refer to application report SBAA035, available for download at www.ti.com. ELECTRICAL CHARACTERISTICS PER DEVICE At TA = +25°C, VS = nominal, CIN = 2.2µF, COUT = 1.0 µF, unless otherwise noted. INPUT VOLTAGE (V) OUTPUT VOLTAGE (V) VS VNOM AT VS (TYP) LOAD REGULATION (%) NO LOAD CURRENT (mA) EFFICIENCY (%) IQ 10% TO 100% LOAD (2) 75% LOAD (1) BARRIER CAPACITANCE (pF) CISO 0% LOAD 100% LOAD VISO = 750Vrms TYP TYP TYP 30 18 74 26 14 20 18 80 22 7.35 14 25 20 81 30 9 9.45 12 20 23 82 31 ±14.25 ±15 ±15.75 11 20 27 85 24 13.2 4.75 5 5.25 7 15 14 83 33 12 13.2 11.4 12 12.6 7 20 15 87 47 10.8 12 13.2 ±11.4 ±12 ±12.6 6 20 16 88 35 DCP021515P, U 13.5 15 16.5 14.25 15 15.75 6 20 15 88 42 DCP022405P 21.6 24 26.4 4.85 5 5.35 6 10 13 81 33 DCP022405U 21.6 24 26.4 4.75 5 5.25 10 15 13 81 33 DCP022405DP, U 21.6 24 26.4 ±4.75 ±5 +5.25 6 15 12 80 22 DCP022415DP, U 21.6 24 26.4 ±14.25 ±15 ±15.75 6 25 16 79 44 PRODUCT MIN TYP MAX MIN TYP MAX TYP MAX DCP020503P, U 4.5 5 5.5 3.13 3.3 3.46 19 DCP020505P, U 4.5 5 5.5 4.75 5 5.25 DCP020507P, U 4.5 5 5.5 6.65 7 DCP020509P, U 4.5 5 5.5 8.55 DCP020515DP, U 4.5 5 5.5 DCP021205P, U 10.8 12 DCP021212P, U 10.8 DCP021212DP, U (1) (2) 100% load current = 2W/VNOM (typ) Load regulation = (VOUT at 10% load - VOUT at 100%)/VOUT at 75% load Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series 3 DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 DEVICE INFORMATION NVA PACKAGE DIP-14 (Single-DIP) (Top View) VS 1 0V 2 NVA PACKAGE DIP-14 (Dual-DIP) (Top View) 14 SYNC VS 1 0V 2 14 SYNC DCP02 DCP02 0V 5 0V 5 +VOUT 6 +VOUT 6 NC 7 -VOUT 7 8 NC Table 1. Pin Description (Single-DIP) NC Table 3. TERMINAL FUNCTIONS (Dual-DIP) TERMINAL NAME 8 TERMINAL NO. DESCRIPTION NAME NO. DESCRIPTION VS 1 Voltage input VS 1 Voltage input 0V 2 Input side common 0V 2 Input side common 0V 5 Output side common 0V 5 Output side common +VOUT 6 +Voltage out +VOUT 6 +Voltage out NC 7, 8 Not connected –VOUT 7 –Voltage out SYNC 14 Synchronization pin NC 8 Not connected SYNC 14 Synchronization pin DVB PACKAGE SO-28 (Single-SO) (Top View) DVB PACKAGE SO-28 (Dual-SO) (Top View) VS 1 28 SYNC 0V 2 27 NC VS 1 28 SYNC 0V 3 26 NC 0V 2 27 NC 0V 3 26 NC DCP02 DCP02 0V 12 17 NC +VOUT 13 16 NC NC 14 15 NC 0V 12 17 NC +VOUT 13 16 NC 14 15 NC -VOUT Table 2. TERMINAL FUNCTIONS (Single-SO) Table 4. TERMINAL FUNCTIONS (Dual-SO) TERMINAL NAME NO. DESCRIPTION TERMINAL VS 1 Voltage input NAME 0V 2 Input side common VS 1 Voltage input 0V 3 Input side common 0V 2 Input side common 0V 12 Output side common 0V 3 Input side common +VOUT 13 +Voltage out 0V 12 Output side common Not connected +VOUT 13 +Voltage out –VOUT 14 –Voltage out NC SYNC 14, 15, 16, 17, 26, 27 28 Synchronization pin NC SYNC 4 Submit Documentation Feedback NO. 15, 16, 17, 26, 27 28 DESCRIPTION Not connected Synchronization pin Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 TYPICAL CHARACTERISTICS At TA = +25°C, unless otherwise noted. DCP020505P VOUT vs TEMPERATURE (75% Load) 60 5.04 50 5.02 40 5.00 30 VOUT (V) Emission Level, Peak (dBmA) DCP020505P CONDUCTED EMISSIONS (500mA Load) 20 4.96 10 4.94 0 4.92 -10 4.90 -20 0.15 1 5.4 10 -40 30 0 20 40 60 80 100 Temperature (°C) Figure 1. Figure 2. DCP021205P VOUT vs LOAD DCP021205P POWER OUT vs TEMPERATURE (400mA Load) 2.5 5.3 2.0 5.2 1.5 5.1 5.0 1.0 0.5 4.9 0 0 20 40 60 80 100 -50 Load (%) -25 0 25 50 Temperature (°C) 75 Figure 3. Figure 4. DCP0212 EFFICIENCY vs LOAD DCP020505P OUTPUT AC RIPPLE (20MHz Band) 100 450 100 DCP1212DP 400 80 350 DCP1205P 0.1mF Ripple (mVPP) Efficiency (%) -20 Frequency (MHz) POUT (W) VOUT (V) 4.98 60 40 300 250 200 150 100 20 1m F 50 0 0 0 25 50 75 100 0 Load (%) 200 400 Load Current (mA) Figure 5. Figure 6. Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series 5 DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 FUNCTIONAL DESCRIPTION OVERVIEW This interference occurs because of the small variations in switching frequencies between the DC/DC converters. The DCP02 offers up to 2W of unregulated output power from a 5V, 12V, 15V, or 24V input source with a typical efficiency of up to 89%. This efficiency is achieved through highly integrated packaging technology and the implementation of a custom power stage and control IC. The circuit design uses an advanced BiCMOS/DMOS process. The DCP02 overcomes this interference by allowing devices to be synchronized to one another. Up to eight devices can be synchronized by connecting the SYNC pins together, taking care to minimize the capacitance of tracking. Stray capacitance (> 10pF) has the effect of reducing the switching frequency, or even stopping the oscillator circuit. It is also recommended that power and ground lines be star-connected. POWER STAGE The DCP02 uses a push-pull, center-tapped topology switching at 400kHz (divide-by-2 from an 800kHz oscillator). It should be noted that if synchronized devices are used at start up, all devices will draw maximum current simultaneously. This configuration can cause the input voltage to dip; if it dips below the minimum input voltage (4.5V), the devices may not start up. A 2.2µF capacitor should be connected close to the input pins. OSCILLATOR AND WATCHDOG The onboard 800kHz oscillator generates the switching frequency via a divide-by-2 circuit. The oscillator can be synchronized to other DCP02 circuits or an external source, and is used to minimize system noise. A watchdog circuit checks the operation of the oscillator circuit. The oscillator can be stopped by pulling the SYNC pin low. The output pins will be tri-stated, which occurs in 2µs. If more than eight devices are to be synchronized, it is recommended that the SYNC pins be driven by an external device. Details are contained in Application Report SBAA035, External Synchronization of the DCP01/02 Series of DC/DC Converters, available for download from www.ti.com. THERMAL SHUTDOWN CONSTRUCTION The DCP02 is protected by a thermal-shutdown circuit. If the on-chip temperature exceeds +150°C, the device will shut down. Once the temperature falls below +150°C, normal operation resumes. The basic construction of the DCP02 is the same as standard ICs; there is no substrate within the molded package. The DCP02 is constructed using an IC, rectifier diodes, and a wound magnetic toroid on a leadframe. Since there is no solder within the package, the DCP02 does not require any special printed circuit board (PCB) assembly processing. This architecture results in an isolated DC/DC converter with inherently high reliability. SYNCHRONIZATION In the event that more than one DC/DC converter is needed onboard, beat frequencies and other electrical interference can be generated. VSUPPLY VOUT 1 VS CIN (1) SYNC DCP COUT 1.0mF 02 0V 0V VS VOUT 2 VOUT 1 + VOUT 2 CIN(1) SYNC 0V COM DCP COUT 1.0mF 02 0V NOTE: (1) CIN requires a low-ESR ceramic capacitor: 5V to 15V version is 2.2mF; 24V version is minimum 0.47mF. Figure 7. Connecting the DCP02 in Series 6 Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 ADDITIONAL FUNCTIONS DISABLE/ENABLE The DCP02 can be disabled or enabled by driving the SYNC pin using an open drain CMOS gate. If the SYNC pin is pulled low, the DCP02 will be disabled. The disable time depends upon the external loading; the internal disable function is implemented in 2µs. Removal of the pull down causes the DCP02 to be enabled. Capacitive loading on the SYNC pin should be minimized in order to prevent a reduction in the oscillator frequency. Connect the positive VOUT from one DCP02 to the negative VOUT (0V) of another (see Figure 7). If the SYNC pins are tied together, the self-synchronization feature of the DCP02 prevents beat frequencies on the voltage rails. The SYNC feature of the DCP02 allows easy series connection without external filtering, thus minimizing cost. The outputs on the dual-output DCP02 versions can also be connected in series to provide two times the magnitude of VOUT, as shown in Figure 8. For example, a dual 15V DCP022415D could be connected to provide a 30V rail. DECOUPLING Connecting the DCP02 in Parallel Ripple Reduction The high switching frequency of 400kHz allows simple filtering. To reduce ripple, it is recommended that a 1µF capacitor be used on VOUT. Dual outputs should both be decoupled to pin 5. A 2.2µF capacitor on the input is also recommended. If the output power from one DCP02 is not sufficient, it is possible to parallel the outputs of multiple DCP02s, as shown in Figure 9. Again, the SYNC feature allows easy synchronization to prevent power-rail beat frequencies at no additional filtering cost. Connecting the DCP02 in Series Multiple DCP02 isolated 2W DC/DC converters can be connected in series to provide nonstandard voltage rails. This configuration is possible by using the floating outputs provided by the galvanic isolation of the DCP02. VSUPPLY VS CIN(1) +VOUT DCP 02 0V COM -VOUT +VOUT COUT 1.0mF COUT 1.0mF 0V -VOUT NOTE: (1) CIN requires a low-ESR ceramic capacitor: 5V to 15V version is 2.2mF; 24V version is minimum 0.47mF. Figure 8. Connecting Dual Outputs in Series VSUPPLY VOUT VS CIN (1) SYNC DCP COUT 1.0mF 02 0V 0V VS VOUT 2 x Power Out CIN(1) SYNC 0V COM DCP COUT 1.0mF 02 0V NOTE: (1) CIN requires a low-ESR ceramic capacitor: 5V to 15V version is 2.2mF; 24V version is minimum 0.47mF. Figure 9. Connecting Multiple DCP02s in Parallel Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series 7 DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 APPLICATION INFORMATION The DCP01B, DCV01, and DCP02 are three families of miniature DC/DC converters providing an isolated unregulated voltage output. All are fabricated using a CMOS/DMOS process with the DCP01B replacing the familiar DCP01 family that was fabricated from a bipolar process. The DCP02 is essentially an extension of the DCP01B family, providing a higher power output with a significantly improved load regulation. The DCV01 is tested to a higher isolation voltage. TRANSFORMER DRIVE CIRCUIT Transformer drive transistors have a characteristically low value of transistor on resistance (RDS); thus, more power is transferred to the transformer. The transformer drive circuit is limited by the base current available to switch on the power transistors driving the transformer and the characteristic current gain (beta), resulting in a slower turn-on time. Consequently, more power is dissipated within the transistor, resulting in a lower overall efficiency, particularly at higher output load currents. SELF-SYNCHRONIZATION The input synchronizations facility (SYNCIN) allows for easy synchronizing of multiple devices. If two to eight devices (maximum) have their respective SYNCIN pins connected together, then all devices will be synchronized. Each device has its own onboard oscillator. This oscillator is generated by charging a capacitor from a constant current and producing a ramp. When this ramp passes a threshold, an internal switch is activated that discharges the capacitor to a second threshold before the cycle is repeated. When several devices are connected together, all the internal capacitors are charged simultaneously. OPTIMIZING PERFORMANCE Optimum performance can only be achieved if the device is correctly supported. The very nature of a switching converter requires power to be instantly available when it switches on. If the converter has DMOS switching transistors, the fast edges will create a high current demand on the input supply. This transient load placed on the input is supplied by the external input decoupling capacitor, thus maintaining the input voltage. Therefore, the input supply does not see this transient (this is an analogy to high-speed digital circuits). The positioning of the capacitor is critical and must be placed as close as possible to the input pins and connected via a low-impedance path. The optimum performance primarily depends on two factors: 1. Connection of the input and output circuits for minimal loss. 2. The ability of the decoupling capacitors to maintain the input and output voltages at a constant level. PCB Design The copper losses (resistance and inductance) can be minimized by the use of mutual ground and power planes (tracks) where possible. If that is not possible, use wide tracks to reduce the losses. If several devices are being powered from a common power source, a star-connected system for the track must be deployed; devices must not be connected in series, as this will cascade the resistive losses. The position of the decoupling capacitors is important. They must be as close to the devices as possible in order to reduce losses. See the PCB Layout section for more details. When one device passes its threshold during the charge cycle, it starts the discharge cycle. All the other devices sense this falling voltage and, likewise, initiate a discharge cycle so that all devices discharge together. A subsequent charge cycle is only restarted when the last device has finished its discharge cycle. 8 Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 Decoupling Ceramic Capacitors Input Capacitor and the Effects of ESR All capacitors have losses because of internal equivalent series resistance (ESR), and to a lesser degree, equivalent series inductance (ESL). Values for ESL are not always easy to obtain. However, some manufacturers provide graphs of frequency versus capacitor impedance. These graphs typically show the capacitor impedance falling as frequency is increased (as shown in Figure 10). As the frequency increases, the impedance stops decreasing and begins to rise. The point of minimum impedance indicates the resonant frequency of the capacitor. This frequency is where the components of capacitance and inductance reactance are of equal magnitude. Beyond this point, the capacitor is not effective as a capacitor. If the input decoupling capacitor is not ceramic with <20mΩ ESR, then at the instant the power transistors switch on, the voltage at the input pins falls momentarily. Should the voltage fall below approximately 4V, the DCP detects an under-voltage condition and switches the DCP drive circuits to the off state. This detection is carried out as a precaution against a genuine low input voltage condition that could slow down or even stop the internal circuits from operating correctly. A slow-down or stoppage would result in the drive transistors being turned on too long, causing saturation of the transformer and destruction of the device. Z XC XL 0 fO Frequency Normal startup should occur in approximately 1ms from power being applied to the device. If a considerably longer startup duration time is encountered, it is likely that either (or both) the input supply or the capacitors are not performing adequately. Z = Ö(XC - XL)2 + (ESR)2 Where: XC is the reactance due to the capacitance. XL is the reactance due to the ESL. fO is the resonant frequency. Figure 10. Capacitor Impedance vs Frequency At fO, XC = XL; however, there is a 180° phase difference resulting in cancellation of the imaginary component. The resulting effect is that the impedance at the resonant point is the real part of the complex impedance; namely, the value of the ESR. The resonant frequency must be well above the 800kHz switching frequency of the DCP and DCVs. The effect of the ESR is to cause a voltage drop within the capacitor. The value of this voltage drop is simply the product of the ESR and the transient load current, as shown: VIN = VPK – (ESR × ITR) Following detection of a low input voltage condition, the device switches off the internal drive circuits until the input voltage returns to a safe value. Then the device tries to restart. If the input capacitor is still unable to maintain the input voltage, shutdown recurs. This process is repeated until the capacitor is charged sufficiently to start the device correctly. Otherwise, the device will be caught up in a loop. (1) Where: VIN is the voltage at the device input. VPK is the maximum value of the voltage on the capacitor during charge. ITR is the transient load current. The other factor that affects the performance is the value of the capacitance. However, for the input and the full wave outputs (single-output voltage devices), ESR is the dominant factor. For 5V to 15V input devices, a 2.2µF low-ESR ceramic capacitor ensures a good startup performance. For the remaining input voltage ranges, 0.47µF ceramic capacitors are recommended. Tantalum capacitors are not recommended, since most do not have low-ESR values and will degrade performance. If tantalum capacitors must be used, close attention must be paid to both the ESR and voltage as derated by the vendor. Output Ripple Calculation Example DCP020505: Output voltage 5V, Output current 0.4A. At full output power, the load resistor is 12.5Ω. Output capacitor of 1µF, ESR of 0.1Ω. Capacitor discharge time 1% of 800kHz (ripple frequency): tDIS = 0.0125µs τ = C × RLOAD τ = 1 × 10-6 × 12.5 = 12.5µs VDIS = VO(1 – EXP(–tDIS/τ)) VDIS = 5mV By contrast, the voltage dropped because of ESR: VESR = ILOAD × ESR VESR = 40mV Ripple voltage = 45mV Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series 9 DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 Clearly, increasing the capacitance has a much smaller effect on the output ripple voltage than does reducing the value of the ESR for the filter capacitor. DUAL OUTPUT VOLTAGE DCP AND DCVs The voltage output for the dual DCPs is half wave rectified; therefore, the discharge time is 1.25µs. Repeating the above calculations using the 100% load resistance of 25Ω (0.2A per output), the results are: τ = 25µs tDIS = 1.25µs VDIS = 244mV VESR = 20mV Ripple Voltage = 266mV This time, it is the capacitor discharging that contributes to the largest component of ripple. Changing the output filter to 10µF, and repeating the calculations, the result is: Ripple Voltage = 45mV. This value is composed of almost equal components. The previous calculations are given only as a guide. Capacitor parameters usually have large tolerances and can be susceptible to environmental conditions. PCB LAYOUT Figure 11 and Figure 12 illustrate a printed circuit board (PCB) layout for the two conventional (DCP01/02, DCV01), and two SO-28 surface-mount packages (DCP02U). Figure 13 shows the schematic. Input power and ground planes have been used, providing a low-impedance path for the input power. For the output, the common or 0V has been connected via a ground plane, while the connections for the positive and negative voltage outputs are conducted via wide traces in order to minimize losses. The location of the decoupling capacitors in close proximity to their respective pins ensures low losses due to the effects of stray inductance, thus improving the ripple performance. This location is of particular importance to the input decoupling capacitor, because this capacitor supplies the transient current associated with the fast switching waveforms of the power drive circuits. 10 The SYNCIN pin, when not being used, is best left as a floating pad. A ground ring or annulus connected around the pin prevents noise being conducted onto the pin. If the SYNCIN pin is to be connected to one or more SYNCIN pins, then the linking trace should be narrow and must be kept short in length. In addition, no other trace should be in close proximity to this trace because that will increase the stray capacitance on this pin. In turn, the stray capacitance affects the performance of the oscillator. Ripple and Noise Careful consideration should be given to the layout of the PCB in order to obtain the best results. The DCP02 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 connect the power to the input of DCP02. If this connection is not possible, then the supplies must be connected in a star formation with the traces made as wide as possible. If the SYNCIN pin is being used, then the trace connection between device SYNCIN pins should be short to avoid stray capacitance. If the SYNCIN 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, thereby ensuring minimum losses. A good quality, low-ESR ceramic capacitor placed as close as practical across the input reduces reflected ripple and ensures a smooth startup. A good quality. low-ESR capacitor (ceramic preferred) placed as close as practical across the rectifier output terminal and output ground gives the best ripple and noise performance. See Application Bulletin SBVA012, DC-to-DC Converter Noise Reduction, for more information on noise rejection. THERMAL MANAGEMENT Due to the high power density of this device, it is advisable to provide ground planes on the input and output. Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 Figure 11. Example of PCB Layout, Component-Side View Figure 12. Example of PCB Layout, Non-Component-Side View Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series 11 DCP02 Series www.ti.com SBVS011K – MARCH 2000 – REVISED FEBRUARY 2008 CON3 CON1 1 VS1 C1 2 0V1 SYNC 14 VS3 JP1 6 +V1 R1 C3 C2-1 C2 R2 C5 C4-1 C11 0S3 2 3 +V3 13 DCP02xP C13 R5 5 COM1 1 JP1 26 NC 12 R6 7 -V1 28 27 DCP02xU C12 COM3 C4 SYNC C14 C15 14 -V3 CON4 CON2 1 VS2 C6 SYNC 14 2 0V2 6 +V2 R3 C8 C7-1 5 COM2 R4 C10 C9-1 JP2 C16 0S4 2 3 +V4 13 DCP02xP C7 1 VS4 R7 26 NC 12 R8 -V2 JP2 DCP02xU C18 COM4 C9 7 C17 SYNC 28 27 C20 C19 14 -V4 (1) Capacitors C2−1, C4−1, C7−1, and C9−1 are through-hole plated components connected in parallel with C2, C4, C7, and C9 (1206 SMD), respectively. (2) For optimum low-noise performance, use low-ESR capacitors. (3) Do not connect the SYNC pin jumper (JP1−JP4) if the SYNC function is not being used. (4) Connections to the power input should be made with a minimum wire of 16/0.2 twisted pair, with the length kept short. (5) VSx and 0Vx are input supply and ground respectively (x represents the channel). (6) +Vx and −Vx are the positive and negative outputs, referenced to a common ground COMx. (7) JPx are the links used for self-synchronization; if this facility is not being used, the links should be unconnected. (8) R1−R8 are the power output loads; do not fit these if an external load is connected. (9) CON1 and CON2 are DIL-14; CON3 and CON4 are SO-28 packages. (10) NC = not connected. Figure 13. Example of PCB Layout, Schematic Diagram 12 Submit Documentation Feedback Copyright © 2000–2008, Texas Instruments Incorporated Product Folder Link(s): DCP02 Series PACKAGE OPTION ADDENDUM www.ti.com 28-Aug-2010 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/ Ball Finish MSL Peak Temp (3) Samples (Requires Login) DCP020503P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP020503U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020505P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP020505U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020505U/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples DCP020505U/1KE4 ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples DCP020505UE4 ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020507P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP020507U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020507U/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples DCP020509P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP020509U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020509U/1K OBSOLETE SOP DVB 12 TBD Call TI Call TI Samples Not Available DCP020515DP ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP020515DU ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP020515DU/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR DCP021205P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP021205PE4 ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples Request Free Samples Purchase Samples DCP021205U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR DCP021205U/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR DCP021212DP ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples Purchase Samples DCP021212DU ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP021212DU/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples DCP021212P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP021212U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP021212U/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples DCP021515P ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP021515PE4 ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP021515U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP021515U/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples Addendum-Page 1 PACKAGE OPTION ADDENDUM www.ti.com Orderable Device 28-Aug-2010 Status (1) DCP022405DP ACTIVE DCP022405DU DCP022405P Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/ Ball Finish MSL Peak Temp (3) Samples (Requires Login) PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples Purchase Samples DCP022405U ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP022415DP ACTIVE PDIP NVA 7 25 Pb-Free (RoHS) CU NIPDAU N / A for Pkg Type Request Free Samples DCP022415DU ACTIVE SOP DVB 12 28 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Request Free Samples DCP022415DU/1K ACTIVE SOP DVB 12 1000 Pb-Free (RoHS) CU NIPDAU Level-3-260C-168 HR Purchase Samples (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. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. 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Addendum-Page 2 MECHANICAL DATA MPDS106A – AUGUST 2001 – REVISED NOVEMBER 2001 DVB(R-PDSO-G12/28) –A– 28 PLASTIC SMALL-OUTLINE 18,10 17,70 11,20 10,82 C 0°–8° 15 1,27 0,40 F 7,60 7,40 –B– D 10,65 10,01 0,25 M B M Index Area 1 14 0,30 0,10 2,65 2,35 0,75 0,25 x 45° Base Plane –C– Seating Plane 1,27 G 0,32 0,23 0,51 0,33 0,10 0,25 M C A M B S 4202104/B 11/01 G. Lead width, as measured 0,36 mm or greater above the seating plane, shall not exceed a maximum value of 0,61 mm. H. Lead-to-lead coplanarity shall be less than 0,10 mm from seating plane. I. Falls within JEDEC MS-013-AE with the exception of the number of leads. NOTES: A. All linear dimensions are in millimeters. B. This drawing is subject to change without notice. C. Body length dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, and gate burrs shall not exceed 0,15 mm per side. D. Body width dimension does not include inter-lead flash or portrusions. Inter-lead flash and protrusions shall not exceed 0,25 mm per side. E. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the cross-hatched area. F. Lead dimension is the length of terminal for soldering to a substrate. • POST OFFICE BOX 655303 DALLAS, TEXAS 75265 POST OFFICE BOX 1443 HOUSTON, TEXAS 77251–1443 • 1 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. 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