STEVAL-ISQ009V1 STMicroelectronics

STEVAL-ISQ009V1 Load share controller demonstration board based on the L6615 Data brief Features Three paralleled DC-DC converter modules (in synchronous buck topology, managed by STs L6910) Output currents shared through ST current sharing controller L6615 Innovative use of a MOSFET as both the OR- ing element (replacing OR-ing diode) and sensing element (R ) DS(on) RoHS compliant Description STEVAL-ISQ009V1 The STEVAL-ISQ009V1 demonstration board is composed of three identical sections It is possible to verify that disabling one section (daughterboards) and a motherboard. (through the relevant switch on the motherboard) Each daughterboard is capable of performing DC- does not cause overvoltage on the output or DC conversion starting from +5 VDC and is overcurrent in other sections. In the same way, designed to deliver 3.3 V / 5 A to the load. enabling one section (with the other two already running) does not cause negative output voltage The input terminals of the motherboard are drop or a short to ground, and current sharing is connected to a +5 VDC external source and the established. output terminals to the load. The board can accommodate up to three DC-DC converters. The motherboard contains the circuitry necessary to perform current sharing (utilizing the L6615) and to isolate a failed section from the load. It is designed to be adaptable to all power supplies (compatible with the L6615 absolute maximum ratings) having remote sense pins. By changing just a few components, it can be modified for new specifications. It is possible to build a system to supply a 10 A load at +3.3 V in a 2+1 redundant configuration. That is, whenever three sections are running, each of them supplies 3.33 A, a value lower than its nominal capability. If one of them is switched off, the system is able to supply the load, and each section carries 5 A. DC-DC conversion management is performed by the L6910. February 2010 Doc ID 17166 Rev 1 1/5 For further information contact your local STMicroelectronics sales office. www.st.com 5 2 . 2 2 2 3 2 2 2 2 %4 2 2 Schematic diagrams STEVAL-ISQ009V1 1 Schematic diagrams Figure 1. Single daughterboard circuit schematic 0- /45 3 0 . 6 4 / % 4% 5 %4 0 . 6& / 3 5 , 0 /- 4 6 . ISQ009v1 schematic 1 - V 2/5 Doc ID 17166 Rev 1 05 // 1 n , 0( 3 /5 , 33 0 / 62%& % 2%& 2 33