EN5367QI Evaluation Board User Guide Jan. 2012 Enpirion EN5367QI DC-DC Converter w/Integrated Inductor Evaluation Board Introduction Thank you for choosing Enpirion, the source for ultra small foot print power converter products This evaluation board user guide applies to EN5367QI. The EN5367QI is a 6A device. In addition to this document, you will also need the latest device datasheet. The EN5367QI features integrated inductor, power MOSFETS, controller, a bulk of the compensation network, and protection circuitry against system faults. This level of integration delivers a substantial reduction in footprint and parts count over competing solutions. The evaluation board is optimized for engineering ease of testing through programming options, clip leads, test points etc. The EN5367QI features a customer programmable output voltage by means of a resistor divider. The resistor divider allows the user to set the output voltage to any value within the range 0.75V to (V -V ). The evaluation board, as IN DROPOUT shipped is populated with a 4 resistor divider option. The upper resistor is fixed and has a phase lead capacitor in parallel. One of 4 lower resistors is selected with the jumper option for different output voltages to change V , retain the OUT upper resistor and capacitor values and change only the lower resistor. This device has no over-voltage protection feature. If making modifications to the board, we strongly recommend the customer to ensure the feedback loop is truly closed before powering up the device especially if the load can not withstand the input voltage. The input and output capacitors are X5R or X7R multi-layer ceramic chip capacitors. The Soft-start capacitor is a small 47nF X7R MLCC. Pads are available to have multiple input and output capacitors. This allows for evaluation of performance over a wide range of input/output capacitor combinations. The jumper labeled LLM/SYNC pin controls the SYNC pin. LLM (light-load mode) function is not available on this part. This pin should be pulled LOW if the SYNC function is not to be used. Do not leave this pin floating or high. The jumper labeled VDROOP should be left grounded. This function is not available on this part. Clip-on terminals are provided for POK, and ENA, pins. Page 1 of 8 EN5367QI Evaluation Board User Guide Jan. 2012 Banana jacks are provided for V and V power terminals. Several signal and IN OUT GND clip-on test points are also provided to measure V , V , and GND nodes. IN OUT A jumper is provided for controlling the Enable signal. Enable may also be controlled using an external switching source by removing the jumper and applying the enable signal to the ENA clip-on terminal. A jumper is also provided to connect a POK pull-up resistor to the input supply. This jumper is especially useful to measure the disable current and eliminates having to subtract the current drawn by the POK resistor. Foot print is also provided for a SMA connector to SYNC input. A switching input to this pin allows the device clock to be phase locked to an external signal. This external clock synchronization allows for moving any offending beat frequency to be moved out-of-band. A swept frequency applied to this pin results in spread spectrum operation and reduces the peaks in the noise spectrum of emitted EMI. The board comes with input decoupling and reverse polarity protection to guard the device against common setup mishaps. Quick Start Guide STEP 1: Set the ENABLE jumper to the Disable Position, as shown in Figure 1. Figure 1: Shows POK, Enable, VDROOP and SYNC/LLM Jumpers. POK PWR jumper as shown connects the pull-up resistor to VIN. Enable jumper shown is in DISABLE position. SYNC/LLM jumper as shown ties this pin Low. VDROOP jumper as shown is low, and should stay grounded. STEP 2: Connect Power Supply to the input power connectors, VIN (+) and GND (-) as indicated in Figure 1 and set the supply to the desired voltage. The device disable current may be measured in this configuration. CAUTION: be mindful of the polarity. Even though the evaluation board comes with reverse polarity protection diodes, it may not protect the device under all conditions. Page 2 of 8