DEMO MANUAL DC2448A-D LTM4636-1 PolyPhase 160A Step-Down Power Module Regulator with Overvoltage and Overtemperature Protection DESCRIPTION Demonstration circuit DC2448A-D features a PolyPhase For high efficiency at low load currents, the MODE PLLIN design using the LTM4636-1EY, a 40A high efficiency, jumper selects pulse-skipping mode for noise sensitive switch mode step-down power Module regulator with applications or Burst Mode operation in less noise sensi- overvoltage and overtemperature protection features. The tive applications. The MODE PLLIN pin also allows the input voltage range is from 9V to 15V. The output volt- LTM4636-1 to synchronize to an external clock signal. age range is 0.6V to 3.3V. The DC2448A-D can deliver a DC2448A-D has the option of choosing both internal nominal 160A output current. DC2448A-D has on-board and external compensation circuits for LTM4636-1. The hot swap circuit that can disconnect input supply and LTM4636-1 data sheet must be read in conjunction with protect the LTM4636-1 and the load under overvoltage this demo manual prior to working on or modifying demo and overtemperature conditions. As explained in the data circuit DC2448A-D. sheet, output current derating is necessary for certain Design files for this circuit board are available. V , V and thermal conditions. The board operates in IN OUT All registered trademarks and trademarks are the property of their respective owners. continuous conduction mode in heavy load conditions. BOARD PHOTO Rev. 0 1DEMO MANUAL DC2448A-D PERFORMANCE SUMMARY Specifications are at T = 25C A PARAMETER CONDITIONS VALUE Input Voltage Range 9V to 15V Output Voltages 0.9V 1.3% Maximum Continuous Output Current Derating is necessary for certain operating conditions. See data sheet for details. 160A DC Operating Frequency 350kHz Efficiency V = 12V, V = 0.9V, I = 160A 86.1% Figure 2 IN OUT OUT Load Transient V V = 12V, V = 0.9V, I = 0A TO 40A 95mV Figure 3 OUT(P-P) IN OUT STEP V Overvoltage Threshold R11=100k 1V OUT Overtemperature Threshold R71=R73=R74=R75=66.5k, V =5V 130C BIAS QUICK START PROCEDURE Demonstration circuit DC2448A-D is an easy way to 4. Vary the input voltage from 9V to 15V and adjust the evaluate the performance of PolyPhase operation of the load current from 0A to 160A. Observe the output LTM4636-1EY. Due to the high input/output current, the voltage regulation, ripple voltage, efficiency and other user should select the proper input supply/load/cable parameters. which can sustain the full load operation. Please refer to 5. (Optional) For optional load transient test, apply an Figure 1 for proper measurement equipment setup and adjustable pulse signal between IOSTEP CLK and GND follow the procedure below: test points. The pulse amplitude sets the load step cur- 1. Place jumpers in the following positions for a typical rent amplitude. Keep the pulse width short (<1ms) and application: pulse duty cycle low (<5%) to limit the thermal stress on the load transient circuit. MODE RUN 6. (Optional) LTM4636-1 can be synchronized to an CCM ON external clock signal. Apply a clock signal (0V to 5V, square wave) on the MODE PLLIN test point. 2. With power off, connect the input power supply, load 7. (Optional) The outputs of LTM4636-1 can track another and meters as shown in Figure 1. Preset the load to 0A supply. The output voltage tracks the voltage on TRACK and V supply to 12V. IN when a valid signal is applied on the test point. 3. Turn on the power supply at the input. The output volt- 8. (Optional) To test the OVP and OTP circuitry of LTM4636-1, age should be 0.9V 1.3% (0.888V to 0.912V). another external 5V power supply is needed at the BIAS pin. Rev. 0 2