NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Sep. 29, 2011 VRAF-08AT51 RoHS Compliant Rev.D Non-Isolated Under-Voltage Lockout High Efficiency Output Enable Fixed Frequency OCP/SCP Low Cost Current Source/Sink Capability Tracking a Reference for Output Voltage Over Voltage Protection (Hiccup Mode) High Power Density Description The Bel VRAF-08AT51 module is a non-isolated, step down dc/dc power converter that operates from a nominal 12 Vdc or wide range 10.8 Vdc to 13.2 Vdc source. This converter is designed specifically to provide bus termination voltages in applications such as DDR (double data rate) memory where the bus termination voltage must closely track the I/O bus voltage. The converter accepts a reference input and uses this to program its output voltage to 50% of the reference. The unit is packaged in compact single-in-line footprint and provides a maximum 8 A output. Standard features include remote on/off, input under-voltage lockout, output over voltage protection. Part Selection Output Voltage 0.9 V Input Voltage 10.8 V - 13.2 V Max. Output Current 8A Max. Output Power 7.2 W Typical Efficiency 69% Model Number VRAF-08AT51 Notes: 1. All part numbers above indicate RoHS 6. Change the second letter "R" to "7" for RoHS 5 part numbers. 2. Add “G” suffix at the end of the model numbers listed above to indicate “Tray Packaging”. Part Number Explanation V R AF – 08 A T5 1 1 2 3 4 5 6 7 1---Vertical Mount 2---RoHS 6, change “R” to “7” means RoHS 5 3---0.65"x0.41" DDR 4---Output current 8A 5---12V narrow range, 10.8-13.2V 6---Vout =0.5Vddq 7---Option Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Sep. 29, 2011 Absolute Maximum Ratings Min Typ Max Input Supply Voltage Parameter -0.5 V - 15 V Input Signal Voltage -0.3 V Operating Temperature Storage Temperature Notes 5.25 V 0 C - 70 C -40 C - 85 C Note: All specifications are typical at 25 C unless otherwise stated. Input Specifications Parameter Min Typ Max Operating Input Voltage 10.8 V 12 V 13.2 V Input Current (full load) - - 1.05 A Input Current (no load) - 25 mA 35 mA 1.2 V 1.8 V 1.89 V - 7 mA 10 mA Parameter Min Typ Max Input Reflected Ripple Current (pk-pk) - 110 mA 180 mA Input Reflected Ripple Current (rms) - 25 mA 60 mA I t Inrush Current Transient - 0.006 A s 0.012 A s Turn on Voltage Threshold 2.6 V - 3.9 V Turn off Voltage Threshold 2.4 V - 3.7 V Reference Voltage Range (Vddq) Remote Off Input Current Notes Input Specifications (continued) 2 2 Notes With simulated source impedance of 1000 nH, 5 Hz to 20 MHz. Use a 100 uF/25 V Tan cap with ESR=0.025 ohm max, at 100 kHz@25°C. 2 Notes: 1. All specifications are typical at 25 C unless otherwise stated. 2. This power module is not internally fused. An input line fuse must always be used. Output Specifications Parameter Output Voltage Set Point Tracking Tolerance (Vddq/2-Vout)/Vout Load Regulation Min - Typ Vddq/2 Max - -1.5% - 1.5% - 3 mV 6 mV Line Regulation - 3 mV 6 mV Output Current 0A - 8A Output DC Current Limit 9.2 A - 14 A Output Ripple and Noise (pk-pk) - 25 mV 50 mV Output Ripple and Noise (rms) - 8 mV 15 mV Short Circuit Surge Transient - 1.1 A s 2 2.2 A s Turn on Time - 2.5 mS 5 mS - 0% 3% 0 uF - 2200 uF Overshoot at Turn on Output Capacitance Notes Vin=12 V, lout=full load Test conditions: 0-20 MHz BW, with 13 X 10uF 0603 ceramics + 1 X 47uF 1206 ceramic at the output. 2 Start up from ENABLE. Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Sep. 29, 2011 Transient Response 12.5% ~ 62.5%Max Load Settling Time 62.5% ~ 12.5%Max Load VO =0.9 V Settling Time - 80 mV 120 mV - 30 uS 50uS - 80 mV 120 mV - 30 uS 50 uS di/dt=1A/uS; Vin12 V; and with 13 X 10uF 0603 ceramics + 1 X 47uF 1206 ceramic at the output. Vddq=1.5V. Note: All specifications are typical at Vin =12 V, Vddq=1.8 V, Io=8 A, Ta= 25°C unless otherwise stated. General Specifications Parameter Efficiency Switching Frequency Min 68% 260 kHz Typ 69% 300 kHz MTBF Max 340 kHz Notes Vin=12 V, Vddq=1.8 V, Io=8 A Calculated Per Bell Core SR-332 (IO = 80% load; Vin=12 V; Ta = 25 C) 6,416,286 hours Dimensions Inches (L × W × H) Millimeters (L × W × H) Weight - 0.65 x 0.41 x 0.40 16.51 x 10.41 x 10.16 2.5 g - Note: All specifications are typical at 25 C unless otherwise stated. Control Specifications Parameter Output Enable Min Typ Max ENABLE High 2V - 5.5 V ENABLE Low 0V - 0.8 V Notes Enable Pin open, the module is off. Efficiency Data Efficiency Efficiency Curve 85.0% 80.0% 75.0% 70.0% 65.0% 60.0% 55.0% 50.0% 45.0% 10.8 V 12.0 V 13.2 V 0.8 2.0 4.0 6.0 8.0 Output Current (A) VRAF-08AT51 Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 Sep. 29, 2011 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Thermal Derating Curve The thermal reference point Tref is shown above. For reliable operation this temperature should not exceed 115C. The output power of the module should not exceed the rated power for the module. Vin=12 V, Vddq=1.8 V Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 8 A Output Sep. 29, 2011 Bel Power Inc., a subsidiary of Bel Fuse Inc. Ripple and Noise Waveform Note: Ripple and noise at Vin=12 V, Vddq=1.5 V, Io=8 A, with 13 X 10uF 0603 ceramics + 1 X 47uF 1206 ceramic at the output, Ta=25 C. Transient Response Waveforms 12.5% to 62.5% load step at Vin=12 V, Vddq=1.5V 62.5% to 12.5% load step at Vin=12 V, Vddq=1.5V Note: Transient response at di/dt=1A/uS, with 13 X 10uF 0603 ceramics + 1 X 47uF 1206 ceramic at the output, Ta=25 C. Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Sep. 29, 2011 Vddq/2 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Output Tracking Test condition: Vin=12 V, Vddq=1.8 V, Io=8 A. Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 Sep. 29, 2011 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Mechanical Outline Pin Connections Pin Function 1 Vin 2 Vddq 3 Vout 4 GND 5 Enable Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 / 8 A Output Bel Power Inc., a subsidiary of Bel Fuse Inc. Sep. 29, 2011 Revision History Date Revision Changes Detail Approval 2011-08-19 A First Release HL 2011-8-23 B Update transient response HL 2011-8-30 C Update transient response HL 2011-9-29 D Update input range HL RoHS Compliance Complies with the European Directive 2002/95/EC, calling for the elimination of lead and other hazardous substances from electronic products. 2011 Bel Fuse Inc. Specifications subject to change without notice. 092911 CORPORATE FAR EAST EUROPE Bel Fuse Inc. 206 Van Vorst Street Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com Bel Fuse Ltd. 8F/ 8 Luk Hop Street San Po Kong Kowloon, Hong Kong Tel 852-2328-5515 Fax 852-2352-3706 www.belfuse.com Bel Fuse Europe Ltd. Preston Technology Management Centre Marsh Lane, Suite G7, Preston Lancashire, PR1 8UD, U.K. Tel 44-1772-556601 Fax 44-1772-888366 www.belfuse.com