19-1871; Rev 0; 12/00 MAX1747 Evaluation Kit Features ♦ Low-Profile Solution, 1.1mm max Height The low-current negative charge-pump circuit is configured for a -7V output; the low-current positive chargepump circuit is configured for a +12V output. Both circuits provide up to 20mA of current. The high-current step-up DC-DC converter or the EV kit’s input source can be used to power either or both charge pumps. The MAX1747 EV kit demonstrates an inductorless and low profile (1.1mm max) solution. Operation up to 1.23MHz allows the use of tiny surface-mount components and provides fast transient response. ♦ Integrated Power MOSFETs ♦ Three Charge-Pump Regulators +5V Output at 200mA +12V Output at 20mA -7V Output at 20mA ♦ High-Current Output Regulated to ±1% ♦ Adjustable Outputs ♦ 1µA Shutdown Current ♦ Switching Frequency Up to 1.23MHz ♦ Fast Transient Response ♦ Surface-Mount Components ♦ Fully Assembled and Tested Ordering Information PART MAX1747EVKIT TEMP.RANGE IC PACKAGE 0°C to +70°C 20 TSSOP Component List DESIGNATION QTY C1, C2, C3, C17 4 5 C5, C7, C20, C21, C22 C6, C8, C14 C9, C11, C12, C15, C16, C19 C10 3 6 1 DESIGNATION QTY 4.7µF, 6.3V X7R ceramic capacitors (1210) Taiyo Yuden LMK325BJ475MD D1–D4 4 200mA, 25V Schottky diodes (SOT23) Fairchild BAT54S 1µF, 16V X5R ceramic capacitors (1206) Murata GRM42-6X5R105K016 R1 1 150kΩ ±1% resistor (0805) R2, R4, R6 3 49.9kΩ ±1% resistors (0805) R3 1 432kΩ ±1% resistor (0805) 0.47µF, 25V X7R ceramic capacitors (1206) Murata GRM42-6X7R474K025 R5 1 280kΩ ±1% resistor (0805) R7 0 Not installed (0805) R8 1 107kΩ ±1% resistor (0805) 0.1µF, 16V X7R ceramic capacitors (0603) Taiyo Yuden EMK107BJ104KA R10 1 1MΩ ±5% resistor (0805) U1 1 MAX1747EUP (20 TSSOP) JU1 1 2-pin header 1500pF, 50V X7R ceramic capacitor (0603) Taiyo Yuden UMK107BJ152KZ JU2, JU3 2 3-pin headers None 3 Shunts (JU1, JU2, JU3) None 1 MAX1747 PC board None 1 MAX1747 data sheet None 1 MAX1747 EV kit data sheet DESCRIPTION C13 1 0.22µF, 10V X7R ceramic capacitor (0603) Taiyo Yuden LMK107BJ224KA C4, C18 0 Not installed (1210) DESCRIPTION ________________________________________________________________ Maxim Integrated Products 1 For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Evaluates: MAX1747 General Description The MAX1747 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board that contains three charge-pump regulators. The first one is a highcurrent step-up DC-DC converter and is configured for a +5V output that provides up to 200mA of current. The other two charge pumps are low-current charge pumps that generate positive and negative voltages. A +3.0VDC to +3.6VDC source can be utilized to power the EV kit input. Evaluates: MAX1747 MAX1747 Evaluation Kit Component Suppliers SUPPLIER PHONE FAX Fairchild 408-822-2000 408-822-2102 Murata 814-237-1431 814-238-0490 Nihon 661-867-2555 661-867-2698 Taiyo Yuden 408-573-4150 408-573-4159 Note: Please indicate that you are using the MAX1747 when contacting these component suppliers. Quick Start The MAX1747 EV kit is fully assembled and tested. Follow these steps to verify board operation. Do not turn on the power supply until all connections are completed. Output 1) Connect a voltmeter to the VOUT pad. 2) Verify that shunts are present across pins 1 and 2 of jumpers JU2 (SUPN) and JU3 (SUPP). Verify that jumper JU1 (SHDN) does not have a shunt installed. 3) Connect a +3.0VDC to +3.6VDC power supply to the VIN pad. 4) Connect the supply ground to the GND pad. 5) Turn on the power supply and verify that the highcurrent step-up DC-DC converter output (VOUT) is +5V. The low-current negative charge pump provides -7V output; other negative output voltages can be evaluated by replacing two voltage feedback resistors. The output can be adjusted to -8V. The low-current positive charge pump provides a +12V output (VP); other output voltages can be evaluated by replacing two voltage feedback resistors. The output can be adjusted up to +13V. Jumper options allow either charge-pump circuit to be fed power from the EV kit’s input (VIN) or the high-current step-up DC-DC converter output (VOUT). The MAX1747 switching frequency is determined by resistor R8 and the voltage supplied to the EV kit input pad (VIN). Applying a voltage in the range of +3.0V to +3.6V to the VIN pad causes the switching frequency to operate in the 980kHz to 1.23MHz range, respectively. An off-board CMOS or bipolar transistor can control the EV kit’s shutdown feature. Jumper Selection Shutdown Mode The MAX1747 EV kit features a shutdown mode that reduces the EV kit’s quiescent current to less than 60µA (typ). The two-pin jumper, JU1, selects the shutdown modes for the MAX1747. Table 1 lists the selectable jumper options. Table 1. Jumper JU1 Functions 6) Verify that the low-current negative charge pump output (VN) is -7V. SHUNT LOCATION SHDN PIN OUTPUT 7) Verify that the low-current positive charge pump output (VP) is +12V. None Connected to VIN via R8 MAX1747 enabled, operation up to 1.23MHz Installed Connected to GND Shutdown mode, VOUT = 0 For instructions on selecting the feedback resistors for other output voltages, see the Evaluating Other Output Voltages section. The input voltage range is +3.0V to +3.6V when selecting the output voltage. Detailed Description The MAX1747 EV kit contains a high-current step-up DC-DC converter and two low-current charge-pump circuits. The EV kit’s voltage input range is from +3.0V to +3.6V as configured, and can be extended to operate in the +2.7V to +5.5V range. The high-current stepup DC-DC converter output voltage can be adjusted from +VIN to +5.5V with resistors. 2 A CMOS open-drain or bipolar open-collector transistor can be connected to the EV kit SHDN pad and ground to control the shutdown mode. The shunt for jumper JU1 must be removed for this feature to function. Low-Current Negative Voltage Source The MAX1747 EV kit features an option to choose which voltage source feeds the low-current negative charge-pump circuit. Jumper JU2 selects the input voltage source for pin SUPN on the MAX1747. Table 2 lists the options. _______________________________________________________________________________________ MAX1747 Evaluation Kit SHUNT LOCATION SUPN PIN OPERATING MODE 1, 2 Connected to VOUT VOUT voltage source feeds low-current negative input 2, 3 Connected to VIN Input voltage source, VIN feeds low-current negative input Low-Current Positive Voltage Efficiency The MAX1747 EV kit features an option to improve the low-current positive charge pump efficiency for low output voltages at VP. Jumper JU3 selects the voltage source for the maximum pump voltage, and thus, maximum efficiency. Table 3 lists the options. Low-Current Positive Charge-Pump Output Voltages (VP) The MAX1747 EV kit’s low-current positive chargepump output is set to +12V by feedback resistors (R3, R4). To generate output voltages other than +12V, select different external voltage-divider resistors (R3, R4). Refer to Output Voltage Selection in the MAX1747 data sheet for instructions on selecting the resistors. Jumper JU4 is provided to improve the efficiency of the low-current positive charge pump for output voltages under 10V. See Table 3 for the jumper selection of output voltage ranges. Table 3. Jumper JU3 Functions SHUNT LOCATION DIODE D1 OPERATING MODE 1, 2 Connected to VOUT VP > 10V; VOUT feeds D1 2, 3 Connected to VIN VP < 10V; VIN feeds D1 Evaluating Other Output Voltages High-Current Step-Up DC-DC Converter Output Voltages (VOUT) The MAX1747 EV kit’s high-current step-up DC-DC converter output is set to +5V by feedback resistors (R1, R2). To generate output voltages other than +5V, select different external voltage-divider resistors (R1, R2). Refer to Output Voltage Selection in the MAX1747 data sheet for instructions on selecting the resistors. Low-Current Negative Charge-Pump Output Voltages (VN) The MAX1747 EV kit’s low-current negative chargepump output is set to -7V by feedback resistors (R5, R6). To generate output voltages other than -7V, select different external voltage-divider resistors (R5, R6). Refer to Output Voltage Selection in the MAX1747 data sheet for instructions on selecting the resistors. See Table 2 for the jumper selection of input voltage ranges. _______________________________________________________________________________________ 3 Evaluates: MAX1747 Table 2. Jumper JU2 Functions 4 GND VN -7V GND C7 1µF C8 0.47µF +3.0V TO +3.6V VIN SHDN VIN RDY R R 1 L D3 2 1 L 2 C1 4.7µF 6.3V D4 R8 107k 1% 3 3 R5 280k 1% C16 0.1µF 3 1 2 C18 OPEN JU2 R10 1M C15 0.1µF VIN VOUT C17 4.7µF 6.3V JU1 C10 1500pF C13 0.22µF R6 49.9k 1% C20 1µF C9 0.1µF R7 SHORT 5 11 8 10 12 13 3 6 C21 1µF INTG SHDN REF FBN DRVN SUPN RDY IN U1 PGND 16 MAX1747 GND 7 18 SUPM TGND TGND CXN CXP FBP DRVP SUPP FB OUT 2 1 17 19 9 14 15 4 20 3 3 C14 0.47µF C12 0.1µF C11 0.1µF C19 0.1µF R2 49.9k 1% D2 D1 R1 150k 1% 1 2 R 2 L R L 1 R4 49.9k 1% C6 0.47µF JU3 R3 432k 1% 3 1 2 C22 1µF C5 1µF VIN VOUT +12V C4 OPEN GND VP C3 4.7µF 6.3V C2 4.7µF 6.3V +5V GND VOUT Evaluates: MAX1747 MAX1747 Evaluation Kit Figure 1. MAX1747 EV Kit Schematic _______________________________________________________________________________________ MAX1747 Evaluation Kit Evaluates: MAX1747 1.0" 1.0" Figure 2. MAX1747 EV Kit Component Placement Guide— Component Side Figure 3. MAX1747 EV Kit PC Board Layout—Component Side 1.0" Figure 4. MAX1747 EV Kit PC Board Layout—Solder Side Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 5 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.