1 Watt SLC Dual Series DC/DC Converters Features ! Low Cost ! Operating Range of 4.5 to 5.5 Volts ! Semi-Regulated 1 Watt Outputs • ±5, 12, 15 and 7, 14, 17 Volt Outputs ! Simple Five Terminal Operation ! Small SLC Package, Fits in 0.19 sq.in. of PCB Area ! Low Noise Operation ! 750 VDC Isolation Voltage ! 5 Year Warranty Description Selection Chart The CALEX SLC Dual is specifically designed to provide bipolar output voltages and isolation for 5 volt digital systems. The series provides semi-regulated outputs of 5, 12 and 15 volts for directly driving your circuits or 7, 14 and 17 volt outputs for driving three terminal regulators. Model The high efficiency operation of typically 74% for a 12 volt output means efficient use of your system power. Easy five terminal operation makes using the converter a snap. Just plug it in and you are ready to solve those nasty analog problems that arise when only 5 volt digital power is available in your system. Input Range VDC Output Min Max VDC 5D5.075SLC 4.5 5.5 ±5.0 ±75 Power W ¾ 5D7.070SLC 4.5 5.5 ±7.0 ±70 1 5D12.040SLC 4.5 5.5 ±12.0 ±40 1 5D14.035SLC 4.5 5.5 ±14.0 ±35 1 5D15.033SLC 4.5 5.5 ±15.0 ±33 1 5D17.030SLC 4.5 5.5 ±17.0 ±30 1 mA 1 Watt SLC Dual Series Block Diagram A 2401 Stanwell Drive • Concord, California 94520 • Ph: 925/687-4411 or 800/542-3355 • Fax: 925/687-3333 • www.calex.com • Email: [email protected] 1 3/2001 1 Watt SLC Dual Series DC/DC Converters Input Parameters* Model 5D5.075SLC Voltage Range MIN TYP MAX 5D7.070SLC 5D12.040SLC 5D14.035SLC 5D15.033SLC 5D17.030SLC 4.50 5.00 5.50 75 Units VDC Reflected Ripple (1) TYP Input Current Full Load No Load Efficiency TYP TYP TYP Switching Frequency TYP 105 kHz Maximum Input Overvoltage 100 mSec max MAX 6.5 VDC 200 25 75 50 250 27 78 40 240 27 79 245 30 79 250 35 79 mA P-P 255 40 79 mA % Output Parameters* Model Output Voltage Output Voltage Accuracy (2) Output Balance (3) Rated Load Range Load Regulation (4) 20% - 75% Full Load 75% - 100% Full Load Cross Regulation (5) MIN TYP MAX TYP MIN MAX 5D5.075SLC 5D7.070SLC ±5 4.75 5.00 5.25 ±7 6.65 7.00 7.35 5D12.040SLC 5D14.035SLC 5D15.033SLC 5D17.030SLC ±12 11.40 12.00 12.50 0 ±75 0 ±70 0 ±40 Line Regulation (6) TYP TYP Temperature Coefficient TYP Short Circuit Protection to Common TYP ±15 14.50 15.00 15.50 ±17 16.50 17.00 17.50 0 ±35 0 ±33 0 ±30 < 0.5% TYP TYP TYP Noise, 0 to 20MHz (1) ±14 13.50 14.00 14.50 VDC VDC % 5.0 2.5 mA % 1.0 1.5 % 30 mV P-P 1.3 60 Units %/% 40 400 ppm/°C (7) NOTES parameters measured at Tc=25 °C case temperature, * All nominal input voltage and full rated load unless otherwise noted. Refer to the CALEX Application Notes for definition of terms, measurement circuits and other information. (1) Noise is measured per CALEX Application notes. All noise measurements are made with a 10uF/35V Tantalum capacitor connected directly across the input and outputs. Measurement bandwidth is 0-20 MHz. (2) Output voltage accuracy is measured at 75% of maximum load. (3) Output balance is the percent difference in voltage from the plus to the minus output at 75% of maximum load. (4) (5) (6) (7) (8) (9) Load regulation is measured relative to 75% maximum load. Load regulation is specified with both outputs changing simultaneously. Cross regulation is measured relative to 75% maximum load. Cross regulation is measured by operating the +output at 75% of maximum load and varying the -output as specified. The change in the +output is the cross regulation. Line regulation is for a 1% change in the input voltage. Current limiting must be accomplished by using a current limited source or fuse in the input circuit. The case thermal impedance is specified as the case temperature rise over ambient per package watt dissipated. Specifications subject to change without notice. A General Information The 1 Watt SLC series provides isolated, semi-regulated outputs of ±5, 7, 12, 14, 15, and 17 VDC. The high efficiency low noise push-pull design operates at 105 kHz which reduces to a minimum your external filter requirements. The converter is packaged in a non-conductive plastic case and can be water washed after being assembled to your PC board. Applying The Input Figure 1 shows the recommended input connections for the SLC Dual series. C1 may not be required when the power source is less than 2" from the unit. The source impedance should be less than 0.5 ohm over the frequency range of DC to 165 kHz. A 10µF/10V solid Tantalum capacitor will satisfy the requirements for C1, and should be placed as close to the converter as possible. C1 = 10µF if converter is more than 2" from the main power source. C2 = 2.2µF minimum, 10 µF typical, may be spread around your board. Figure 1. Typical input and output connections for the SLC Dual series. 2401 Stanwell Drive • Concord, California 94520 • Ph: 925/687-4411 or 800/542-3355 • Fax: 925/687-3333 • www.calex.com • Email: [email protected] 2 3/2001 1 Watt SLC Dual Series DC/DC Converters General Specifications* All Models Units Isolation Isolation Voltage Input to Output 10µA Leakage MIN 750 VDC Input to Output Capacitance TYP 30 pF Environmental Case Operating Range No Derating Storage Range Thermal Impedance (8) Unit Weight Case Material MIN MAX MIN MAX TYP TYP -40 °C 85 -40 °C 100 58 °C/Watt 0.1 oz Non Conductive Plastic Mechanical tolerances unless otherwise noted: X.XX dimensions: ±0.020 inches X.XXX dimensions: ±0.010 inches Output Short Circuit Protection Pin 1 2 3 4 5 This series is only protected for momentary output short circuits to common so a fast acting fuse or input current limiting is recommended to protect the converter. If output shorts are possible then the protection circuit should not be omitted as it serves to prevent unlimited current from flowing in the case of an overcurrent at the load. Function +INPUT -INPUT -OUTPUT CMN +OUTPUT Operation With Changing Input Voltage Very Low Noise Input Circuit The output will change proportionally to a change in the input voltage. The typical output voltage change is 1.2% per 1% change in input voltage. Figure 2 shows a very low noise input circuit that may be used with the converters. This circuit will reduce the input reflected ripple current to less than 10 mA peak to peak. L1 should be sized to handle the maximum DC current of your application. C1 must be used if L1 is required in the circuit. Low Noise Output Circuit The circuit shown in Figure 3 can be used to reduce the output noise to below 8 mV p-p over a 20 MHz bandwidth. Size inductor L2 appropriately for the maximum expected load current. All the ground connections must be as short as possible back to the CMN pin. The filter should be placed as close as possible to the converter, even if your load is at some distance. A Figure 2. This circuit will reduce the input reflected ripple current to less than 10 mA peak to peak. See the discussion in the text for selecting C1 and L1. Applying The Output Figure 1 shows the typical output connection for the converter. C2 is required for proper operation of the outputs. C2 should be at least 2.2µF minimum and can be made up of the bypass capacitors already used in your application. A low ESR 10µF Tantalum capacitor is recommended. Decreasing the ESR of C2 will lower the output noise. Figure 3. Operation With Light Loads Single Ended Loads This converter uses a semi-regulated design. The output voltage will vary as the load is changed, increasing as the load is decreased. See the Output Voltage vs. Output Load curve for more information. The SLC Dual series may be operated in a single ended mode to get 10, 14, 24, 28, 30 or 34 volt outputs. The circuit of Figure 4 should be used for single ended operation. The CMN pin should be left floating from your application ground. C2, C3 = . 2.2 µF, 10 µF TYPICAL L2 = 1 µH - 5 µH This circuit can reduce the output noise to below 8mV P-P over a 20 MHz bandwidth. Size L2 for the maximum expected load current. Place as close as possible to the converter. 2401 Stanwell Drive • Concord, California 94520 • Ph: 925/687-4411 or 800/542-3355 • Fax: 925/687-3333 • www.calex.com • Email: [email protected] 3 3/2001 1 Watt SLC Dual Series DC/DC Converters from ambient by knowing that the case temperature rise is approximately 58°C per package watt dissipated. For example: If a 5D12.040SLC is delivering 0.9 watts at 5V input, at what ambient could it expect to run with no additional cooling such as moving air? Efficiency is approximately 73% which leads to an input power of 1.23 watts. The internal power loss is 1.23 - .9 = 0.33 watts. The case temperature rise will be 0.33W x 58°C/W= 19.1°C. This number is subtracted from the maximum case temperature rating of 85°C to get 65.9°C, which is the maximum ambient operating temperature. Figure 4. This example calculation is for an application with no extra air flow for cooling. Extra cooling air will greatly effect the maximum ambient temperature. Exact internal power loss depends upon the efficiency, input voltage, and load in the application. Unipolar output voltages up to 34 volts may be generated by operating the SLC Dual Series converters in a single ended mode. The CMN pin should not be directly used in your application. Grounding The above example is a rough approximation to the maximum ambient temperature. Because of the difficulty of defining ambient temperature, these calculations should be verified by actual measurement before committing to a production design. The input and output sections are fully floating and isolated from each other. They may be operated fully floating or with a common connection between the input and output. Temperature Derating The 1 Watt Output SLC series can be operated up to a +85°C case temperature. Case temperature can be roughly calculated Typical Performance: (Tc=25°C) LOAD REGULATION Line Regulation 15 8 10 Normalized Output (%) NORMALIZED OUTPUT (%) 10 6 4 2 0 -2 5 0 -5 -10 -4 -6 0 10 20 30 40 50 60 70 80 90 -15 4.50 100 5.00 5.25 5.50 Input Voltage (VDC) EFFICIENCY Vs. LOAD INPUT CURRENT Vs. INPUT VOLTAGE 80 0.30 75 0.25 INPUT CURRENT (AMPS) EFFICIENCY (%) A 4.75 OUTPUT LOAD (%) 70 65 60 55 50 0.20 0.15 0.10 0.05 0.00 0 10 20 30 40 50 60 70 80 90 100 0.0 LOAD (%) 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (VDC) 2401 Stanwell Drive • Concord, California 94520 • Ph: 925/687-4411 or 800/542-3355 • Fax: 925/687-3333 • www.calex.com • Email: [email protected] 4 3/2001