AP6502-EVM 340kHz 18V 2A Synchronous DCDC Buck Converter Description The AP6502 is a 340kHz switching frequency external compensated synchronous DCDC buck converter. It has integrated low RDSON high and low side MOSFETs. The AP6502 is available in a standard Green SO-8EP with exposed PAD for improved thermal performance. AP6502 is also available in SO-8 package and is RoHS compliant. The AP6502 enables continues load current of up to 2A with efficiency as high as 95%. The AP6502 features current mode control operation, which enables fast transient response times and easy loop stabilization. • Gaming Consoles • TV sets and Monitors • Set Top Boxes Performance Spec of AP6502SPG-EVM Parameter Input voltage Output Current Output Voltage Output Voltage Ripple Transient Response • Distributed power systems • Home Audio • Consumer electronics Conditions Range 4.75V to 18V Peak Deviation Load step 1.0A/us to 2A/us Switching Frequency Efficiency Figure 1. Evaluation Board AP6502 Document number: Rev. 1 - 0 Performance Value 12V 2A 3.3V 20mVp-p 140mV 340kHz 90% Figure 2. Efficiency vs Load Current 1 of 4 www.diodes.com April 2012 © Diodes Incorporated AP6502-EVM 340kHz 18V 2A Synchronous DCDC Buck Converter Quick Start Guide The AP6502-EVM has a simple layout and allows access to the appropriate signals through test points. To evaluate the performance of the AP6502, follow the procedure below: 1. Connect a power supply to the input terminals Vin and GND. Set Vin to 12V. 2. Connect the positive terminal of the electronic load to Vout and negative terminal to GND. 3. EN has a positive voltage through a 100K pull-up to Vin. No supply input is required for EN. Note: To use the EN function drive EN above 1.3V to start the converter and below 0.4V to stop the converter. 4. The evaluation board should now power up with a 3.3V output voltage. 5. Check for the proper output voltage of 3.3V(+/-1%) at the output terminals Vout and GND. Measurement can also be done with a multimeter with the positive and negative leads between Vout and GND. 6. Set the load to 1.5A through the electronic load. Check for the stable operation of the SW signal on the oscilloscope. Measure the switching frequency. A test point is conveniently located at the head of the inductor. Measurement/Performance Guidelines: 1) The evaluation board has the inductor pad spaced for easy access to measure the inductor current. As shown in the picture, a current probe can be connected to the wire loop to measure the inductor current. 2) When measuring the output voltage ripple, maintain the shortest possible ground lengths on the oscilloscope probe. Long ground leads can erroneously inject high frequency noise into the measured ripple. 3) For efficiency measurements, connect an ammeter in series with the input supply to measure the input current. Connect an electronic load to the output for output current. AP6502 Document number: Rev. 1 - 0 2 of 4 www.diodes.com April 2012 © Diodes Incorporated AP6502-EVM 340kHz 18V 2A Synchronous DCDC Buck Converter EVALUATION BOARD SCHEMATIC BILL OF MATERIALS QTY REF VALUE DESCRIPTION PACKAGE MANUFACTURER MANUFACTURER P/N 1 C1 10nF Ceramic Capacitor, 25V,X5R SM0805 AVX 08055C103KAT2A 2 C5, C9 22uF 1210 AVX 1210YD226KAT2A 3 C3 6.8nF Ceramic Cap, 16V, X5R Ceramic Cap, 50V, X7R SM0805 AVX 08055C682KAT2A 4 C2 10uF Ceramic Capacitor, 10V, X5R 1210 AVX 12103D106KAT2A 5 C6 0.1uF Ceramic Cap, 50V, X7R 0805 AVX 08055C104KAT2A 6 L1 10µh Inductor, 5.0A SMD Wurth Electronics 74477110 7 R1 26.1K Resistor, 1% 0603 Panasonic 8 R2 6.8KΩ Resistor, 1% 0603 Panasonic CRCW060326KIFK EA ERJ-6GEYJ682V 9 R3 10.0k Resistor, 1% 0603 Panasonic ERJ-6ENF1002V 10 R4 100k Resistor, 1% 0603 Panasonic ERJ-6GEYJ104V 11 U1 DC/DC Converter SOP-8LEP/SOP-8 Diodes Inc AP6502 AP6502 Document number: Rev. 1 - 0 3 of 4 www.diodes.com April 2012 © Diodes Incorporated AP6502-EVM 340kHz 18V 2A Synchronous DCDC Buck Converter TOP SILK LAYER TOP LAYER BOTTOM LAYER AP6502 Document number: Rev. 1 - 0 4 of 4 www.diodes.com April 2012 © Diodes Incorporated