USERS MANUAL ISL91110IIN-EVZ, ISL91110II2A-EVZ, ISL91110IIA-EVZ AN1912 Rev 1.00 Evaluation Boards March 12, 2014 Description Key Board Features The ISL91110 is a high-current buck-boost switching regulator Small, compact design for systems using new battery chemistries. It uses Intersils Jumper selectable EN (enabled/disabled) proprietary buck-boost algorithm to maintain voltage regulation, Jumper selectable MODE (auto-PFM/forced-PWM) while providing excellent efficiency and very low output voltage ripple when the input voltage is close to the output voltage. The Connectors, test points, and jumpers for easy probing ISL91110IIN-EVZ, ISL91110II2A-EVZ and ISL91110IIA-EVZ platforms allow quick evaluation of the high performance References features of the ISL91110 buck-boost regulator series. ISL91110 Data Sheet. Specifications The boards are designed to operate at the following operating Ordering Information conditions: Input voltage rating from 1.8V to 5.5V PART NUMBER DESCRIPTION Resistor programmable output voltage on the ISL91110IIA-EVZ ISL91110IIN-EVZ Evaluation Board for ISL91110IINZ Fixed 3.3V output voltage on the ISL91110IIN-EVZ ISL91110II2A-EVZ Evaluation Board for ISL91110II2AZ Fixed 3.5V output voltage on the ISL91110II2A-EVZ ISL91110IIA-EVZ Evaluation Board for ISL91110IIAZ Up to 2A output current (PVIN = 2.5V, V = 3.3V) OUT 2.5MHz switching frequency Operating temperature range: -40C to +85C ISL91110IIAZ VIN PVIN LX1 GND VIN LX2 VOUT VOUT MODE GND FB EN FIGURE 1. ISL91110IIA-EVZ BLOCK DIAGRAM AN1912 Rev 1.00 Page 1 of 8 March 12, 2014 SGND PGNDISL91110IIN-EVZ, ISL91110II2A-EVZ, ISL91110IIA-EVZ Functional description The ISL91110IIN-EVZ, ISL91110II2A-EVZ and ISL91110IIA-EVZ be connected to the V and GND headers on J2. Measure OUT provides simple platforms to demonstrate the feature of the the input and output currents. Calculate efficiency based on ISL91110 buck-boost regulator. The ISL91110IIN-EVZ is for the these measurements. fixed 3.3V output IC ISL91110IINZ. The ISL91110II2A-EVZ is for 11. To test external sync, remove the jumper at J4, then apply an the fixed 3.5V output IC ISL91110II2AZ and the ISL91110IIA-EVZ external clock between 2.75MHz and 3.25MHz on the MODE is for the adjustable output IC ISL91110IIAZ. The Evaluation input (the center pin of header J4). boards have been functionally optimized for best performance of the ISL91110 IC series. The input power and load connections TABLE 1. OUTPUT VOLTAGE PROGRAMMING For ISL91110IIA-EVZ are provided through multi-pin connectors for high current operations. DESIRED OUTPUT VOLTAGE R2 RESISTOR VALUE (V) (k ) The ISL91110IIA-EVZ evaluation board is shown in Figures 4 and 5. The boards enable function is controlled by the on-board jumper 2.0 665 header J3. Similarly the Mode function is controlled by the on-board 2.5 470 jumper header J4. 3.0 365 The schematic of the ISL91110IIA-EVZ evaluation board is shown in Figure 6. The schematic for the ISL91110IIN-EVZ and 3.3 324 ISL91110II2A-EVZ is shown in Figure 7. The PCB layout images 3.4 309 for all layers are shown in Figures 8 and 11. The bill of materials of the ISL91110IIA-EVZ is shown in Table 2. The bill of materials 4.0 249 of the ISL91110IIN-EVZ and ISL91110II2A-EVZ is shown in 4.5 215 Table 3. 5.0 191 Operating Range The V range of the boards is 1.8V to 5.5V. The V range for the IN OUT ISL91110IIA-EVZ is 2V to 5V. The I range of the boards is 0 to 2A. OUT The operating ambient temperature range is -40C to +85C. LX1 2V/DIV Quick Start Guide LX2 2V/DIV For the ISL91110IIA-EVZ board, the default output voltage is set at 3.3V. Should other output voltages are desired, resistor R2 can V OUT be changed to set to a desired voltage as shown in Table 1 (use a 2V/DIV resistor with 1% accuracy). Refer to the following Quick Setup Guide to configure and EN power-up the board for proper operation. During the power-on I = 200mA 2V/DIV OUT process, the expected waveforms are shown in Figures 2 and 3. 400s/DIV Quick Setup Guide FIGURE 2. ISL91110 START-UP WITH V = 2V and V = 3.3V IN OUT 1. Install jumper on J3, shorting EN to V . IN 2. Install jumper on J4, shorting MODE to V . IN 3. Connect power supply to J1, with voltage setting between 1.8V and 5.5V. LX1 2V/DIV 4. Connect electronic load to J2. 5. Place scope probes on the V test point, and other test LX2 OUT 2V/DIV points of interest. 6. Turn on the power supply. V OUT 7. Monitor the output voltage start-up sequence on the scope. The 2V/DIV waveforms will look similar to that shown in Figures 2 and 3. EN 8. Turn on the electronic load. 2V/DIV I = 200mA OUT 9. Measure the output voltage with the voltmeter. The voltage should regulate within datasheet spec limits. 400s/DIV 10. To determine efficiency, measure input and output voltages FIGURE 3. ISL91110 START-UP WITH V = 4V and V = 3.3V IN OUT at the Kelvin sense test points (S+ and S-), which are part of J1 and J2 headers. The bench power supply can be connected to the PVIN and GND headers on J1. The electronic load can AN1912 Rev 1.00 Page 2 of 8 March 12, 2014