DEMO MANUAL DC2493A LTC3892-2, 60V, Low I Q Multiphase Synchronous Step-Down Converter Description Demonstration circuit 2493A is a high output voltage The DC2493A consumes less than 5A of quiescent cur- capable, high efficiency synchronous PolyPhase buck rent during shutdown and it consumes less than 1mA at a converter featuring the LTC 3892EUH-2. The DC2493A no load condition in Burst Mode operation. The DC2493A has a wide input voltage range from 16V to 55V, and is has a standard operating frequency of 150kHz, but can be capable of delivering up to 30A of output current. The adjusted to frequencies as high as 900kHz. The DC2493 output voltage of the DC2493A is set to 12V, however, is a dual phase step-down converter however it designed the output voltage can go as high as 55V, with certain to be easily transformed to a 4- or 6-phase system by modifications. The DC2493A supports three operation combining two or three DC2493A boards. The LTC3892-2 modes: fixed-frequency modulation, pulse-skipping mode data sheet gives a complete description of these parts, and Burst Mode operation. Fixed-frequency mode of operation, and application information and must be read operation reduces output voltage ripple, and yields a low in conjunction with this quick start guide for demonstra- noise switching spectrum. Burst Mode operation employs tion circuit 2493A. a variable frequency switching algorithm that minimizes Design files for this circuit board are available at the input quiescent current and improves efficiency at DEMO MANUAL DC2493A Quick s tart p D Demonstration circuit 2493A is easy to set up to evaluate the 2. Turn on the circuit by inserting the shunt in header JP2 performance of the LTC3892-2. For proper measurement (RUN) into the ON position. The output voltage should equipment configuration, set up the circuit according to be regulating. Measure V it should measure 12V OUT the diagram in Figure 1. Before proceeding to test, insert 2% (Do not apply more than the rated maximum volt- shunt JP2 (RUN) into OFF position, which connects the age of 55V to the board or the part may be damaged). RUN pin to ground (GND), and thus, shut-down the circuit. 3. Vary the converter load, which should not exceed 30A. NOTE: When measuring the input or output voltage ripple, Note: all four input and output terminals V , V and IN OUT care must be taken to avoid a long ground lead on the two GND equipped with two banana jacks, two-wires oscilloscope probe. Measure the input or output voltage can be used for each terminal to reduce copper looses ripple by touching the probe tip directly across the V or and heat dissipation in the interconnection lines. IN V and GND terminals. See Figure 2 for proper scope OUT 4. Vary the input voltage from 16V to 55V V should OUT probe technique. measure 12V 2%. 1. With the DC2394 set up according to the proper mea- 5. Set output current to zero and move jumper JP1 (MODE) surement and equipment in Figure 1, apply 20V at V . IN into Burst Mode position and measure V it should OUT Measure V it should read 0V. If desired, one can OUT register 12V 2%. measure the shutdown supply current at this point. 6. Set output current to zero and move jumper JP2 (MODE) The supply current will be approximately 5A, or less, into PLS SKIP position and measure V it should in shutdown. OUT register 12V 2%. Figure 1. Proper Measurement Equipment Setup dc2493af 2 ure roce