Evaluates: MAX8526/MAX8527/MAX8528 19-4163 Rev 0 6/08 MAX8526 Evaluation Kit General Description Features The MAX8526 evaluation kit (EV kit) is a fully assembled 1.425V to 3.6V Input-Voltage Range and tested surface-mount PCB demonstrating the 1.2V Output Voltage MAX8526 low-dropout (LDO) regulator. The EV kit comes assembled with a MAX8526EUD+ circuit that Up to 3A Output Current (Limited by Power steps down a 1.425V to 3.6V input-voltage range to a Dissipation and Dropout) 1.2V output capable of sourcing up to 2A of continuous Low-Dropout Voltage (200mV max at 2A) output current with a maximum dropout voltage of only 200mV. Other features of the EV kit include a logic-con- Power-OK (POK) Output (MAX8527 Only) trolled shutdown mode (EN) and adjustable output volt- Power-On Reset (POR) Output (MAX8528 Only) age through feedback resistors R1 and R2. The EV kit can also be used to evaluate the MAX8527, Fully Assembled and Tested which features a POK output that goes high impedance once the output is within 10% of its regulation value. The EV kit can also be used to evaluate the MAX8528, Ordering Information which features a POR output that goes high impedance 150ms (typ) after the output has risen above 90% of its PART TYPE final value. Both the POK and POR features require an MAX8526EVKIT+ EV Kit external pullup resistor to IN. See the Detailed +Denotes lead-free and RoHS-compliant. Description of Hardware section for more details. Although the EV kit is optimized for 2A output current, the part is capable of supporting up to 3A output cur- rent (limited by power dissipation and dropout). Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION 2.2F 10%, 6.3V X5R ceramic R1 1 698 1% resistor (0603) capacitor (0603) R2 1 499 1% resistor (0603) C1 1 TDK C1608X5R0J225K R3, R4 0 Not installed, resistors (0603) Murata GRM185R60J225K LDO regulator (14 TSSOP) 10F 20%, 6.3V X5R ceramic U1 1 Maxim MAX8526EUD+ capacitor (1206) C2 1 1 Shunt TDK C3216X5R0J106M Murata GRM31CR70J106K 1 PCB: MAX8526 Evaluation Kit+ JU1 1 3-pin header Component Suppliers SUPPLIER PHONE WEBSITE Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com TDK Corp. 847-803-6100 www.component.tdk.com Note: Indicate that you are using the MAX8526, MAX8527, or MAX8528 when contacting these component suppliers. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX8526 Evaluation Kit Quick Start Detailed Description of Hardware Recommended Equipment Output-Voltage Selection Before beginning, the following equipment is needed: The MAX8526/MAX8527/MAX8528 feature an adj- ustable output voltage from 0.5V to 3.4V, using two MAX8526 EV kit external resistors connected as a voltage-divider to FB, One 4V, 2A variable-output power supply as shown in Figure 1. The output voltage is set by the Dummy load capable of sinking 2A following equation: Digital multimeter (DMM) R1 VV=+1 OUT FB R2 Procedure The MAX8526 EV kit is fully assembled and tested. where V is 0.5V. Choose R2 < 1k to optimize quies- FB Follow the steps below to verify board operation. cent current, accuracy, and high-frequency power- Caution: Do not turn on power supplies until all con- supply rejection. To simplify resistor selection: nections are completed. 1) Preset the power supply to 1.425V and turn off the V OUT RR12=1 power supply. V FB 2) Verify that a shunt is across pins 1-2 of JU1 to enable the device. Shutdown Mode The MAX8526 EV kit features 3-pin jumper JU1 to con- 3) Connect the positive lead of the power supply to the trol the enable (EN) input. For normal operation, con- VIN pad on the EV kit, and the negative lead of the nect EN to IN by placing a shunt across pins 1-2. To power supply to the GND pad on the EV kit. shut down the device, pull EN to GND by placing a 4) Connect the positive input of the DMM to the VOUT shunt across pins 2-3. During shutdown, an internal pad on the EV kit, and the negative input of the 10k resistor pulls down the output. DMM to the GND pad on the EV kit to measure the output voltage. Power-OK (POK) (MAX8527 Only) The EV kit can also evaluate the MAX8527 IC, which 5) Turn on the power supply and verify that the output features a power-OK (POK) output to indicate the status voltage is 1.2V 1.4%. of the output. POK remains high when the regulator out- 6) Sweep the input voltage from 1.425V to 3.6V. Verify put is within 10% of its nominal output voltage. If the that the output voltage is 1.2V 1.4% over the entire output voltage falls or rises outside this range, POK input range. transitions low. This open-drain output requires an 7) Set the power supply to 2V. external pullup resistor to IN. Connect POK to IN by installing a 100k pullup resistor R4. 8) Connect the 2A load between the VOUT and GND pads on the EV kit. Power-On Reset (POR) (MAX8528 Only) 9) Verify that the output voltage is 1.2V 1.4%. The EV kit can also evaluate the MAX8528 IC, which features a power-on-reset (POR) output that transitions high 150ms (typ) after the output has risen above 90% of its final value. If the part is in shutdown mode, falls below 90% of the nominal output voltage, or experi- ences a short-circuit/thermal fault, POR immediately transitions low. This open-drain output requires an external pullup resistor to IN. Connect POR to IN by installing a 100k pullup resistor R3. Table 1. Jumper JU1 Functions SHUNT POSITION EN PIN MODE 1-2* Connected to IN Normal operation 2-3 Connected to GND Shutdown mode *Default position. 2 Evaluates: MAX8526/MAX8527/MAX8528