DEMO MANUAL DC2230A-A LTM4636 40A DC/DC Module Regulator DESCRIPTION Demonstration circuit 2230A-A features the LTM 4636EY, also allows the LTM4636 to synchronize to an external a 40A high efficiency, switch mode step-down power clock signal. DC2230A-A has the option of choosing both Module regulator. The input voltage range is from 4.7V to internal and external compensation circuit for LTM4636. 15V. For input voltage range from 4.7V to 5.5V, short PV Tying the PHASMD pin to different voltage generates cer- CC pin to V pin with R8 = R21 = 0 and remove R17. The tain phase difference between MODE PLLIN and CLKOUT. IN output voltage range is 0.6V to 3.3V. Derating is necessary The LTM4636 data sheet must be read in conjunction with for certain V , V , frequency and thermal conditions. The this demo manual prior to working on or modifying demo IN OUT board operates in continuous conduction mode in heavy circuit DC2230A-A. load conditions. For high efficiency at low load currents, Design files for this circuit board are available at the MODE PLLIN jumper selects pulse-skipping mode for DEMO MANUAL DC2230A-A PERFORMANCE SUMMARY PARAMETER CONDITIONS/NOTES VALUE Input Voltage Range 4.7V to 15V Output Voltages 1.0V 1.3% Maximum Continuous Output Current Derating is Necessary for Certain Operating Conditions. See Data Sheet for Details. 40ADC Operating Frequency 350kHz Efficiency V = 12V, V = 1.0V, I = 40A 87.7% (see Figure 2) IN OUT OUT Load Transient V = 12V, V = 1.0V, I = 0A to 10A 81mV (see Figure 3) IN OUT STEP QUICK START PROCEDURE 4. Vary the input voltage from 6V to 15V and adjust the Demonstration circuit 2230A-A is an easy way to evalu- load current from 0A 40A. Observe the output volt- ate the performance of the LTM4636EY. Please refer to age regulation, ripple voltage, efficiency, and other Figure1 for proper measurement equipment setup and parameters. follow the procedure below. 5. (Optional) For optional load transient test, apply an 1. Place jumpers in the following positions for a typical adjustable pulse signal between IOSTEP CLK and GND application: test points. The pulse amplitude sets the load step cur- MODE RUN rent amplitude. Keep the pulse width short (<1ms) and CCM ON pulse duty cycle low (<5%) to limit the thermal stress on the load transient circuit. 2. With power off, connect the input power supply, load 6. (Optional) LTM4636 can be synchronized to an external and meters as shown in Figure 1. Preset the load to 0A clock signal. Place the JP1 jumper on EXT CLK and and V supply to 12V. IN apply a clock signal (0V to 5V, square wave) on the 3. Turn on the power supply at the input. The output volt- MODE PLLIN test point. age should be 1.0V 1.3% (0.987V to 1.013V). dc2230aaf 2