MIC2165 5A Evaluation Board Adaptive On-Time DC-DC Controller Featuring Hyper Light LoadTM Hyper Speed ControlTM Family General Description The MIC2165 DC-DC controller operates over an input supply range of 4.5V to 28V and provides a regulated output at up to 25A of output current. The output voltage is adjustable down to 0.8V with a typical accuracy of ±1% and the device operates at a switching frequency of 600kHz. The switching frequency remains fairly constant with changes in input voltage and output load. Micrel’s Hyper Speed ControlTM architecture allows for ultrafast transient response while reducing the output capacitance and also makes (High VIN)/(Low VOUT) operation possible. The MIC2165 utilizes an adaptive TON ripple control architecture. An undervoltage lockout feature is provided to ensure proper operation under power-sag conditions. An internal soft-start feature is provided to reduce the inrush current. Fold-back current limit and “hiccup” mode shortcircuit protection and thermal shutdown ensures protection of the IC during fault conditions. Note: This evaluation board is for 5A applications. Datasheet and supporting documentation can be found on Micrel’s web site at: www.micrel.com. Requirements The MIC2165 evaluation board requires an input power source that is able to maintain greater than 7.0V. The output load can either be an active or passive load. Precautions The evaluation board does not have reverse polarity protection. Applying a negative voltage to the VIN terminal may damage the device. In addition, the maximum VIN operating voltage of the MIC2165, 5A evaluation board is 28V. Exceeding 29V on VIN could damage the device. Getting Started 1. Connect an external supply to VIN terminal. Apply desired input voltage to the VIN (J1) and ground (J3) terminals of the evaluation board, paying careful attention to polarity and supply voltage (7V < VIN < 28V). An ammeter may be placed between the input supply and the VIN terminal to the evaluation board. Ensure that the supply voltage is monitored at the VIN terminal. The ammeter and/or power lead resistance can reduce the voltage supplied to the input. 2. Connect the load to the VOUT and ground terminals. The load can be either passive (resistive) or active (as in an electronic load). An ammeter can be placed between the load and the VOUT (J2) terminal. Ensure that the output voltage is monitored at the VOUT terminal. The default VOUT is set to 1.2V. This can be adjusted by changing the feedback resistors. See “Output Voltage” section. 3. Enable the MIC2165. The EN pin is connected to VIN through R2 on the evaluation board. The output of the MIC2165 turns on when VIN exceeds the UVLO threshold. The output of the MIC2165 may be turned off by shorting the EN pin to ground. An external connection on the board provides easy access to the enable pin. Output Voltage The output voltage on the MIC2165 evaluation board is adjustable. It is set by adjusting the feedback resistors (R7 and R4) and can be calculated as follows: VOUT = VREF × (1 + R8 ) R4 where VREF = 0.8V. The evaluation board is preset for a 1.2V output, but it can easily be modified by removing R4 and R8 and replacing them with the values that yield the desired output voltage. The total voltage divider resistance R4+R8 is recommended to be 7.5kΩ. Once R8 is selected, R4 can be calculated using: R4 = R8 × VREF VOUT − VREF R4 = R 8 × 0 .8 V VOUT − 0.8 V For VREF = 0.8V: The output voltage should not be set to exceed 5V due to the 6.3V rating of the output capacitor. If an output voltage greater than 5V is desired, the output capacitor must be replaced with another capacitor that has a higher voltage rating. Hyper Speed Control is a trademark of Micrel, Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com June 2010 M9999-060210-A Micrel, Inc. MIC2165 5A Evaluation Board Ordering Information Part Number Description Package MIC2165YMME IC 10-pin ePad MSOP MIC2165YMME 5A EV Evaluation Board 10-pin ePad MSOP Evaluation Board Schematic MIC2165, 7V-28VIN to 1.2VOUT/5A Bill of Materials Item Part Number 06035C104KAT2A C1,C2,C6,C9 GRM188R71H104KA93D C1608X7R1H104K 0805ZD106KAT2A C3 C4 GRM21BR61A106KE19L June 2010 TDK 0.1µF Ceramic Capacitor, X7R, Size 0603, 50V 4 10µF Ceramic Capacitor, X5R, Size 0805, 10V 1 4.7µF Ceramic Capacitor, X7R, Size 1210, 50V 1 220µF Aluminum Capacitor, SMD, 35V 1 (3) AVX Murata 12105C475KAZ2A AVX B41125A7227M Qty AVX Murata(2) TDK GRM32ER71H475KA88L Description (1) C2012X5R1A106M C3225X7R1H475M C5 Manufacturer Murata TDK EPCOS(4) 2 M9999-060210-A Micrel, Inc. MIC2165 5A Evaluation Board Bill of Materials (Continued) Item Part Number 06035C102KAT2A C7 GRM188R71H102KA01D C1608X7R1H102K 06035C472KAT2A C8 C10,C11 GRM188R71H472KA01D Murata AVX SD103BWS-7 1nF Ceramic Capacitor, X7R, Size 0603, 50V 1 4.7nF Ceramic Capacitor, X7R, Size 0603, 50V 1 100µF Ceramic Capacitor, X5R, Size 1210, 6.3V 2 Small Signal Schottky Diode 1 1.8µH Inductor, 7.41A Saturation Current 1 Dual, 30V, 6.9A, N-Channel MOSFET, 17.5mΩ Rds(on) @ 4.5V 1 AVX Murata 12106D107MAT2A SD103BWS Qty. TDK TDK GRM32ER60J107ME20L Description AVX C1608X7R1H472K C3225X5R0J107M D1 Manufacturer Murata TDK MCC(5) (6) DIODE INC Cooper Bussmann(7) L1 DR1030-1R8 Q1 FDS6994S R1,R5 CRCW06032R21FKEA Vishay Dale(9) 2.21Ω Resistor, Size 0603, 1% 2 R2,R3 CRCW060310K0FKEA Vishay Dale 10kΩ Resistor, Size 0603, 1% 2 R4 CRCW06034K99FKEA Vishay Dale 4.99kΩ Resistor, Size 0603, 1% 1 R6 CRCW060319K6FKEA Vishay Dale 19.6kΩ Resistor, Size 0603, 1% 1 R7 CRCW08051R21FKEA Vishay Dale 1.21Ω Resistor, Size 0805, 1% 1 R8 CRCW06032K49FKEA Vishay Dale 2.49kΩ Resistor, Size 0603, 1% 1 R9 CRCW06030000Z0EA Vishay Dale 0Ω Resistor, Size 0603, 5% 1 R10 CRCW060349R9FKEA Vishay Dale 49.9Ω Resistor, Size 0603, 1% 1 600kHz Buck Controller 1 U3 MIC2165YMME Fairchild(8) (10) Micrel. Inc. Notes: 1. AVX: www.avx.com 2. Murata: www.murata.com 3. TDK: www.tdk.com 4. EPCOS: www.epcos.com 5. MCC: www.mccsemi.com 6. Diodes Inc: www.diodes.com 7. Cooper Bussmann: www.cooperbussmann.com 8. Fairchild: www.fairchildsemi.com 9. Vishay: www.vishay.com 10. Micrel, Inc.: www.micrel.com June 2010 3 M9999-060210-A Micrel, Inc. MIC2165 5A Evaluation Board PCB Layout Recommendations Figure 1a. Top Layer Figure 1b. Bottom Layer June 2010 4 M9999-060210-A Micrel, Inc. MIC2165 5A Evaluation Board PCB Layout Recommendations (Continued) Figure 1c. Mid Layer 1 Figure 1d. Mid Layer 2 MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2010 Micrel, Incorporated. June 2010 5 M9999-060210-A