NON-ISOLATED DC/DC CONVERTERS 12 Vdc Input Vddq/2 / 8 A Output VRAF-08xT50 RoHS Compliant Rev.H 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-08xT50 module is a non-isolated, step down dc/dc power converter that operates from a nominal 12 Vdc or wide range 5 Vdc to 13.8 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 Input Voltage Max. Output Current Max. Output Power Typical Efficiency Model Number 0.9 V 10.8 V - 13.2 V 8A 7.2 W 69% VRAF-08AT50 0.9 V 5.0 V - 13.8 V 8A 7.2 W 69% VRAF-08ET50 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”. Absolute Maximum Ratings Parameter Input Supply Voltage Min -0.5 V Input Signal Voltage -0.3 V Operating Temperature Storage Temperature Typ - Max 15 V 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 Operating Input Voltage VRAF-08AT50 VRAF-08ET50 Input Current (full load) VRAF-08AT50 VRAF-08ET50 Input Current (no load) Reference Voltage Range (Vddq) Remote Off Input Current Min Typ Max 10.8 V 5.0 V 12 V 12 V 13.2 V 13.8 V - - 1.05 A 2.2 A - 25 mA 35 mA 1.2 V 1.8 V 1.89 V - 7 mA 10 mA Notes 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 Input Specifications (continued) 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 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 9.2 A - 14 A Output Ripple and Noise (pk-pk) - 25 mV 50 mV Output Ripple and Noise (rms) - 8 mV 15 mV - 2 1.1 A s 2.2 A s - 2.5 mS 5 mS 5 mS 8 mS - 0% 3% 0 uF - 2200 uF Output DC Current Limit Short Circuit Surge Transient Notes Vin=12 V, lout=full load Test conditions: 0-20 MHz BW, with a 22 uF / 6.3 V ceramic capacitor at the output. 2 Turn on Time VRAF-08AT50 VRAF-08ET50 Overshoot at Turn on Output Capacitance Start up from ENABLE. Transient Response 50% ~ 100% Max Load Settling Time 100% ~ 50% Max Load VO =0.9 V Settling Time - 100 mV 200 mV - 20 uS 50 uS - 100 mV 200 mV - 20 uS 50 uS di/dt=0.3 A/uS; Vin12 V; and with a 22 uF / 6.3 V ceramic capacitor at the output. 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 MTBF Typ 69% 300 kHz 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. 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 Control Specifications Parameter Output Enable Min Typ Max Notes ENABLE High 2V - 5.5 V ENABLE Low 0V - 0.8 V 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-08AT50 Efficiency Curve Efficiency 85.0% 75.0% 5.0V 12.0V 13.8V 65.0% 55.0% 45.0% 0.8 2.0 4.0 6.0 8.0 Output Current (A) VRAF-08ET50 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 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 Ripple and Noise Waveform Note: Ripple and noise at Vin=12 V, Vddq=1.8 V, Io=8 A, with a 22 uF/6.3 V X5R ceramic capacitor at the output, Ta=25 C. Transient Response Waveforms 50% to 100% load step at Vin=12 V, Vddq=1.8 V 100% to 50% load step at Vin=12 V, Vddq=1.8 V Note: Transient response at di/dt=0.3 A/uS, with 22 uF/6.3 V X5R ceramic capacitor 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 Vddq/2 / 8 A Output 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 / 8 A Output Mechanical Outline Pin Connections Pin Function 1 Vin 2 Vddq 3 Vout (Vtt) 4 GND 5 Enable RoHS Compliance Complies with the European Directive 2002/95/EC, calling for the elimination of lead and other hazardous substances from electronic products. 2009 Bel Fuse Inc. Specifications subject to change without notice. 042709 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