USERS MANUAL ISL8216MEVAL1Z AN1907 Rev 0.00 Evaluation Board February 10, 2014 Description Recommended Equipment The ISL8216M is a simple and easy to use, high voltage DC/DC 10V to 80V (or other voltage rating depending on desired module. The ISL8216M is ideal for servers, 48V input voltage for the ISL8216M) power supply with at least telecom/datacom applications, 12V/42V automotive and 2A source current capability industrial equipment, and other distributed power Electronic load capable of sinking current up to 4A converters/point-of-load (POL) applications. Only few passive Digital multimeters (DMMs) components and a V setting resistor are needed for a OUT complete a high voltage power design. 100MHz quad-trace oscilloscope The ISL8216MEVAL1Z provides an evaluation platform for the Quick Start ISL8216M. The input voltage range is from 10V to 80V, and the output voltage is preset to five options, 5V, 12V, 20V, 24V and 1. Select the output voltage by using one of the five jumpers 30V. Any other output voltages within the range from 2.5V to JP1 to JP5, for 5V, 12V, 20V, 24V or 30V. 30V can be set with a single resistor. 2. Connect the VIN (J1) and PGND (J2) terminals to a power supply and connect the load to the VOUT (J4) and PGND (J3) terminals. 3. Set the input power supply to desired input voltage between 10V to 80V note that the input voltage must be higher than the selected output voltage. 4. Enable the power supply first before turning on the load, preset the load to 0A. 5. Toggle switch SW1 to the lower position denoted ENABLE. The PGOOD INDICATOR LED should glow in green to indicate proper operation. Use the digital multimeter to check the output voltage. V SELECTION JUMPERS OUT + + LOAD 10V to 80V (0A to 4A) V V V V OUT IN - - FIGURE 1. ISL8216MEVAL1Z BOARD IMAGE AN1907 Rev 0.00 Page 1 of 11 February 10, 2014ISL8216MEVAL1Z external enable circuit is provided on the ISL8216MEVAL1Z Evaluation Board Information evaluation board, see Figure 2. The evaluation board size is 76.2mmx76.2mm (3 inchx3 inch). The FR4 board has four layers, with 2oz copper on the top and V IN the bottom layers, and 1oz copper on the two internal layers. The ENSS board can be used as 4A reference design. Refer to the ISL8216MEVAL1Z Board Schematic on page 4 and BIAS VOLTAGE ISL8216MEVAL1Z Layouts on page 5. All the components on the board, including the solder attachment, are lead free. V OUT Circuits Description Selecting Output Voltage EX EN ON/OFF TP14 The ISL8216MEVAL1Z evaluation board has several output voltages preset for users convenience. The 5V, 12V, 20V, 24V, and 30V can be easily selected by shorting their appropriate jumper. If any other output voltage between 2.5V and 30V is desired, the user can use a FIGURE 2. OPTIONAL EXTERNAL ENABLE CIRCUIT feedback resistor based on Equation 1. To utilize the circuit shown in Figure 2, the user can place 11.3k (EQ. 1) V = 1 + ---------------------------- 1.192V appropriate components on the place holders for R201, D201, OUT R FB R202, Q201, and Q202. NOTE: The output voltage accuracy is not only dependent on the modules A bias voltage of approximately 5.1V is generated from V with a IN internal reference voltage, but also on the feedback resistance accuracy. resistor (R201) in series and a zener diode (D201). R202 is a For higher overall output accuracy, the customer should select a high pull-up resistor of typically 100k, and Q201 and Q202 are accuracy resistor (i.e 0.5%). N-MOSFETs. The external control signal is applied to TP14 (EX EN). When EX EN is logic low, ENSS is pulled to ground to Programming the Switching Frequency disable the module. When EX EN is logic high, ENSS is released The ISL8216M has an internally set fixed switching frequency of to allow the modules soft-start function. The selection of R201 in 300kHz. By adding a resistor between V and RTCT and a series with the zener diode D201 can be calculated as shown in IN capacitor between RTCT and SGND, the modules switching Equation 2: frequency can be adjusted between 200kHz to 600kHz. The V V IN Z R201 = ---------------------------- (EQ. 2) place holders for the resistor (R5) and capacitor (C5) are provided I Z on the ISL8216MEVAL1Z evaluation board for the users convenience. Refer to the ISL8216M datasheet for optimum Where: switching frequency for different conditions. V is the zener diode D201s working voltage, nominal 5.1V. Z The SYNC pin can provide the function to synchronize the I is the zener diode D201s working reverse current, typically Z ISL8216Ms switching frequency to an external source. When about 5mA. frequency synchronization is used, the time constant of R /C T T must be set longer than the period of the sync signal. When the The power dissipation rating should be taken into consideration external sync feature is not used, the customer should tie the when selecting R201. SYNC pin to SGND. Other External Circuits Requirements Optional External Enable Control Circuit Depending on the applications conditions, other external circuits The module can be enabled by an external signal by using an may be required. Table 1 shows these requirements. open-drain device, or by adding an external circuit. This optional TABLE 1. EXTERNAL CIRCUITS REQUIREMENT BASED ON APPLICATION CONDITIONS CONDITIONS EXTERNAL CIRCUITS REQUIREMENTS V Use PGOOD Signal Enable Method PGOOD Delay Circuit 1k Dummy Load Resistor V -BOOT Resistor OUT IN 12V Yes/No Self or External Enable Control No No No >12V Yes Self Enable Yes Yes No >12V No Self Enable No No Yes >12V Yes External Enable Control No No Yes >12V No External Enable Control No No Yes AN1907 Rev 0.00 Page 2 of 11 February 10, 2014 D201 R201 R202 Q201 Q203 Q202