SP6659EB

SP6659EB Evaluation Board Manual Synchronous Buck regulator with up to 94% efficiency 1.5MHz Constant frequency operation 600mA Output Current 2.5V-5.5V Input Voltage range, 0.6V reference allow low output voltage No Schottky diode required Current mode operation Over-temperature protected Low profile SOT23-5 Package & Ceramic Capacitors for small, low profile Power Supply Ideal for PDAs, Digital Cameras, Wireless Modems, Cellular Telephones DESCRIPTION The SP6659 Evaluation Board is designed to help the user evaluate the performance of the SP6659 for use as a single Li-Ion battery Step-Down DC-DC Converter. The SP6659 operates from 2.5V to 5.5V input, with the highest efficiency in the range 3.0V to 4.2V where the Li-Ion battery has the most energy. The SP6659EB evaluation board is a complete power supply circuit to provide ease of evaluation for the DC/DC Converter performance. FIGURE 1. SP6659 1.8V OUTPUT EVALUATION BOARD SCHEMATIC U1 Vin=2.5-5.5V 1 2 3 SP6659 SW 3 4 1 2 L1 2.2 uH CF 100pF Vout=1.8V VIN RUN CIN 4.7uF J1 VFB GND 5 R1 200K COUT 10uF VFB=0.6V R2 100K Rev 08/29/05 SP6659 Evaluation Board Manual Copyright Sipex Corporation USING THE EVALUATION BOARD 1) Powering up the SP6659 Circuit The SP6659 Evaluation Board can be powered from a single Li-Ion battery or a +2.5 to +5.5V power supply. Connect with short leads directly to the “Vin” and “Gnd” posts. Note the SP6659 will remain in “shutdown” until the “RUN” Jumper J1 is applied to the Vin or position 1 to 2. 2) VOUT PROGRAMMING The SP6659 has a dynamically programmable output voltage using 2 feedback resistors to control the output voltage:  Vout  R1 =  − 1 • R 2  0 .6  OR R1   Vout = 0.61 +   R2  Table 1. SP6659EB BILL OF MATERIALS Ref.Des. Qty Manufacturer Part Number Size Component Vendor Eval bd U1 Cin Cout Cf L1 R1 R2 J1 TP 1 1 1 1 1 1 1 1 1 1 3 Sipex Corp Sipex Corp Murata Murata Murata Murata Vishay Vishay Sullins Sullins Mill-Max 146-6595-00 SP6659 GRM188R60J475KE19D GRM21BR60J106KE19 GRM1885C1H101JA01B LQH32CN2R2M53K CRCW06032003F CRCW06031003F PTC36SAAN STC02SYAN 0300-115-01-4727100 1"x1.5" SOT23-5 0603 0805 603 1210 0603 0603 .23x.12 .2x.1 .042" dia SP6659 Eval board 5 pins SOT23 DC/DC Conv Ceramic 4.7uF 6.3V X5R Ceramic 10uF 6.3V X5R Ceramic 100pF 50V COG 2.2uH 790mA 97m Ω 1.5mm thick 200KΩ, 1/10W, 1% 100KΩ, 1/10W, 1% 3 Pin Header Shunt Test Point Female Pin Sipex 408-937-7500 Sipex 408-937-7500 murata.com murata.com murata.com murata.com vishay.com vishay.com 800-digi-key 800-digi-key 800-digi-key Table 2. SP6659 PIN ASSIGNMENT Pin Name RUN GND SW Vin VFB Pin Description Power down control pin. Forcing this pin above 1.5V enables the device. Forcing this pin below 0.3V shuts down the device. Ground pin Switching node Power supply pin Feedback. Receives the feedback voltage from an external resistive divider across output. 2 Pin # 1 2 3 4 5 EVALUATION BOARD LAYOUT FIGURE 2: SP6659EB COMPONENT PLACEMENT FIGURE 3: SP6659EB PC LAYOUT TOP SIDE FIGURE 4: SP6659EB PC LAYOUT BOTTOM SIDE 3