AOZ1020-EVA

AOZ1020-EVA EZBuck™ 2A Simple Buck Regulator Evaluation Board Note General Description The AOZ1020 evaluation board is a fully assembled and tested circuit board built with the AOZ1020 buck regulator IC. It outputs a preset or adjustable voltage at up to 2A of continuous current. The evaluation board requires an input voltage from 4.5V to 16V. The output voltage is preset and can be adjusted from 0.8V to VIN–0.4V The AOZ1020-EVA circuit has features like current limit, short circuit protection, input under voltage lock out, internal soft start and thermal shut down. It operates at a fixed 500kHz switching frequency. The current mode control and integrated internal MOSFET minimize component count, board area and total cost. The AOZ1020 comes in SO-8 packages and is rated over a -40°C to +85°C ambient temperature range. Features ● ● ● ● ● ● ● ● 4.5V to 16V operating input voltage range Output voltage is preset to 3.3V and adjustable down to 0.8V 2A continuous output current Fixed 500kHz PWM operation Internal soft start Cycle-by-cycle current limit Short-circuit protection Thermal shutdown Applications ● ● ● ● ● ● ● Point of load DC/DC conversion PCIe graphics cards Set top boxes DVD drives and HDD LCD panels Cable modems Telecom/networking/datacom equipment Evaluation Board Schematic VIN C5 C1 22µF Ceramic 5V R3 VIN EN C6 PG L1 4.7µH AOZ1020 LX COMP RC VOUT C4 R1 AGND CC PGND FB R2 10kΩ C2, C3 22µF Ceramic Figure 1. Rev. 1.0 December 2007 www.aosmd.com Page 1 of 4 AOZ1020-EVA Component List Ref Designation C1 C2 C3 C4 C5 C6 Cc(2) RC(2) R1(1) R2 R3 L1(2) U1 Notes: 1. For evaluation board with different output voltage, these values might be different. 8 + ( 10 × V O ) 2. Output voltage is set by R1; R1 = ---------------------------------- . Table 1 shows that the value of R1 with typical output voltages. 0.8k Ω Table 1. Value 22µF 22µF 22µF NU 1µF 1000pF 2200pF 8.5kΩ 31.6kΩ 10kΩ 10kΩ 4.7µH AOZ1020AI Description Ceramic Cap, 22uF, 25V, 1210, X5R Ceramic Cap, 22uF, 25V, 1210, X5R Ceramic Cap, 22uF, 25V, 1210, X5R Ceramic Cap, 1uF, 25V, 0603, X5R Ceramic Cap, 1000pF, 50V, 0603, X7R Ceramic Cap, 2200pF, 50V, 0603, X7R Thick Film Res, 1%, 31.6k, 0603 Thick Film Res, 1%, 31.6k, 0603 Thick Film Res, 1%, 10k, 0603 Thick Film Res, 1%, 10k, 0603 Inductor, 4.7uH, 2.9A Buck regulator IC, 2A, 16V Manufacturer Part Number GRM32ER61E226KE15L GRM32ER61E226KE15L GRM32ER61E226KE15L GRM188R61E105KA12D GRM188R71E102K GRM188R71E222K CRCW060385K5FKTAP CRCW060331K6FKTAP CRCW060310K0FKTAP CRCW060310K0FKTAP LQH55DN4R7M03 AOZ1020AI Manufacturer Murata DALE Murata AOS Vo (V) 1.2 1.8 2.5 3.3 5.0 R1 (kΩ) 4.99 12.7 21.5 31.6 52.3 Rev. 1.0 December 2007 www.aosmd.com Page 2 of 4 AOZ1020-EVA PCB Layout Figure 1. Top Silk Screen Figure 2. Top Layer Figure 3. Bottom Layer Rev. 1.0 December 2007 www.aosmd.com Page 3 of 4 AOZ1020-EVA Quick Start Guide 1. Connect the terminals of load to +VOUT pins and GND pins. Set load current to between 0A and 2A. 2. Connect the DC power supply to +VIN pin and GND pins. Set DC power supply voltage to between 4.5V and 16V. 3. Connect EN pin to +VIN or any voltage source which is between 2V and 16V. 4. Turn on DC power supply and the evaluation circuit will start. 5. Measure input voltage at the +VIN pin and GND pins to eliminate the effect of voltage drop on wire between DC power supply and evaluation board. 6. Measure output voltage at the +VOUT pin and GND pins to eliminate the effect of voltage drop on wire between load and evaluation board. 7. Use an oscilloscope to monitor input ripple voltage right across input capacitor C1. 8. Use an oscilloscope to monitor output ripple voltage right across output capacitor C2. This data sheet contains preliminary data; supplementary data may be published at a later date. Alpha & Omega Semiconductor reserves the right to make changes at any time without notice. LIFE SUPPORT POLICY ALPHA & OMEGA SEMICONDUCTOR PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support, device, or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. Rev. 1.0 December 2007 www.aosmd.com Page 4 of 4