19-2517; Rev. 0; 7/02 MAX1702 Evaluation Kit Features ♦ Triple-Output Power Supply 3.3V VI/O Peripheral Output 1.1V VCORE µP Core Output 1.8V, 2.5V, or 3.3V Selectable VMEM Memory Output ♦ Internal Switches ♦ 1MHz Pulse-Width Modulation (PWM) Switching ♦ Adjustable Dead/Low-Battery Settings ♦ 900mA Available from the VI/O Output ♦ 800mA Available from the VMEM Output ♦ 400mA Available from the VCORE Output ♦ Surface-Mount Construction ♦ Fully Assembled and Tested Ordering Information PART MAX1702EVKIT TEMP RANGE IC PACKAGE 0°C TO +70°C 36 QFN (6mm × 6 mm) Component List DESIGNATION QTY C1 C2, C3, C4, C17 C5, C7 C6 C8 1 4 2 1 1 DESCRIPTION 4.7µF ±20%, 6.3V X5R ceramic capacitor (0805) TDK C2012X5R0J475KT or Taiyo Yuden JMK212BJ475MG 10µF ±10%, 6.3V X5R ceramic capacitors (1206) TDK C3216X5R0J106KT or Taiyo Yuden JMK316BJ106KL 1000pF ±10%, 50V X7R ceramic capacitors (0603) TDK C1608X7R1H102KT or Taiyo Yuden UMK107CG102KZ 680pF ±10%, 50V X7R ceramic capacitor (0603) TDK C1608X7R1H681KT or Taiyo Yuden UMK107CG681KZ 0.1µF ±10%, 16V X7R ceramic capacitor (0603) TDK C1608X7R1C104KT or Taiyo Yuden EMK107BJ104KA DESIGNATION QTY DESCRIPTION C9 0 Not installed, capacitor (1210) C10, C12, C14 3 1.0µF ±10%, 10V X5R ceramic capacitors (0603) TDK C1608X5R1A105K C11, C13, C15, C16 0 Not installed, capacitors (0603) C18, C19, C20 3 33pF ±5%, 50V COG ceramic capacitors (0603) TDK C1608COG1H330JT or Taiyo Yuden UMK107CG330JZ JU1 1 3-pin header JU2 1 4-pin header L1, L3 2 4.7µH, 1.32A inductors Sumida CDRH4D28-4R7 L2 1 4.7µH, 900mA inductor Sumida CDRH3D16-4R7NC R1 1 267kΩ ±1% resistor (0603) R2 1 90.9kΩ ±1% resistor (0603) R3 1 137kΩ ±1% resistor (0603) ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 Evaluates: MAX1702B General Description The MAX1702 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board that demonstrates the MAX1702B power-management IC. The IC is optimized for microprocessor-based applications. The MAX1702B integrates three high-performance step-down DC-DC power supplies with associated supervisory and management functions. The first power supply (VI/O) is configured for 3.3V and provides up to 900mA. The second power supply (VCORE) is configured for 1.1V and provides up to 400mA. The third power supply (VMEM) can be configured to 1.8V, 2.5V, or 3.3V and provides up to 800mA. Power management functions include automatic power-up sequencing, power-on reset, manual reset with timer, and two levels of low-battery detection. The EV kit operates with a 2.6V to 5.5V input voltage range, allowing the use of batteries or a regulated DC power supply at the input. MAX1702 Evaluation Kit Evaluates: MAX1702B Component List (continued) DESIGNATION QTY DESCRIPTION R4 1 33kΩ ±5% resistor (0603) R5 1 8.06kΩ ±1% resistor (0603) R6 1 14kΩ ±1% resistor (0603) R7 1 18kΩ ±5% resistor (0603) R8 1 22kΩ ±5% resistor (0603) R9–R12 4 100kΩ ±5% resistors (0603) R13 1 1Ω ±5% resistor (0603) SW1 1 Momentary contact switch U1 1 MAX1702BEGX (36-pin QFN, 6mm x 6mm) — 2 Shunts (JU1, JU2) — 1 MAX1702 PC board — 1 MAX1702B data sheet — 1 MAX1702 EV kit data sheet Quick Start The MAX1702 EV kit is a fully assembled and tested surface-mount board. Follow the steps below for board operation. Do not turn on the power supply until all connections are completed: 1) Verify that a shunt is across pins 1 and 2 of jumper JU1 (ON2). 2) Verify that a shunt is across pins 1 and 3 of jumper JU3 (PGM3). 3) Connect a voltmeter across the VI/O pad and IGND pad to monitor the VI/O output voltage. 4) Connect a voltmeter across the VCORE pad and CGND pad to monitor the VCORE output voltage. 5) Connect a voltmeter across the VMEM pad and MGND pad to monitor the VMEM output voltage. 6) Connect the positive terminal of a 4.5V supply to the VIN pad. Connect the negative terminal to the GND pad. 7) Turn on the power supply and verify that the VI/O output is at 3.3V, VCORE output is at 1.1V, and VMEM output is at 2.5V. 8) Use a voltmeter to verify that LBO, OUTOK, and RSO are at 3.3V and REF is at 1.25V. Detailed Description The MAX1702 EV kit is a fully assembled and tested surface-mount circuit board that demonstrates the capability of the MAX1702B triple-output step-down DC-DC converter optimized for microprocessor-based applications. The MAX1702B integrates three high-performance, 1MHz PWM switching, step-down DC-DC power supplies. These power supplies can be used to power the microprocessor, memory, and I/O peripherals in a single system. The microprocessor VCORE supply is configured for 1.1V and provides up to 400mA. The memory VMEM supply is configurable to 1.8V, 2.5V, or 3.3V and provides up to 800mA. The I/O peripheral VI/O supply is configured for 3.3V and provides up to 900mA. The VPLL output is a filtered output from VCORE that can be used to supply noise-sensitive circuitry such as a phase-lock loop. The EV kit input voltage range is 2.6V to 5.5V and requires up to 2A of current from the source with all outputs fully loaded. Input Source The MAX1702 EV kit has a 2.6V to 5.5V input voltage range that allows the use of batteries or a regulated DC power supply as the power source. However, the EV kit requires a minimum of 3.6V at the input for the VI/O output supply to regulate to 3.3V ±2%. If the input voltage falls below 3.6V, VI/O tracks the input voltage. If VMEM is configured to regulate at 3.3V, it also tracks the input voltage below 3.6V. Input Thresholds The MAX1702B contains two low-battery detection thresholds, dead battery (DBI) and low-battery (LBI), that are used to monitor the input power source to the EV kit. These thresholds are programmable with external resistors. The DBI threshold is set to 2.7V and the Component Suppliers SUPPLIER PHONE FAX WEBSITE Sumida 847-545-6700 847-545-6720 www.sumida.com Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com TDK 847-803-6100 847-390-4405 www.component.tdk.com Note: Please indicate that you are using the MAX1702 when contacting these component suppliers. 2 _______________________________________________________________________________________ MAX1702 Evaluation Kit SHUNT STATUS VMEM OUTPUT (V) PIN CONNECTION 1 and 2 PGM3 connected to VIN 3.3 1 and 3 PGM3 connected to REF 2.5 1 and 4 PGM3 connected to GND 1.8 LBI threshold is set to 3.6V with resistors R1, R2, and R3. If the input source falls below the LBI threshold, the low-battery LBO output is pulled low. The EV kit enters shutdown mode when the input source falls below the DBI threshold. Replace resistors R1, R2, and R3 with different values to reconfigure the DBI and LBI thresholds. Refer to the MAX1702B data sheet to select new resistor values for R1, R2, and R3. Power-Up Sequence The MAX1702 EV kit power-up sequence is initiated when the input voltage is greater than the dead-battery setting (DBI) and greater than the UVLO threshold (2.4V). During initial power-up, VI/O first ramps up in a soft-start mode. Once VI/O reaches its regulation voltage, VMEM ramps to its target in soft-start mode. Finally, once VMEM reaches its regulation voltage, VCORE ramps to its target in soft-start mode. The reset output RSO is held low during this time. Once the VCORE output has reached its target voltage, a 65.5ms reset timer is started. RSO is pulled high when the timer expires. The timer may be manually reset by pushing the momentary switch SW1 or by applying a logic-low signal at the MR pad. The outputs stay on during the manual reset. Table 2. Normal/Sleep Mode (JU1) SHUNT STATUS PIN CONNECTION EV KIT OPERATION 1 and 2 ON2 connected to VIN Normal mode 2 and 3 ON2 connected to GND Sleep mode (VCORE disabled, VI/O and VMEM remain enabled) None ON2 connected to external controller External controller determines operation mode data sheet for instructions on selecting resistors R5 and R6. VMEM can supply 800mA at an output voltage of 3.3V, 2.5V, or 1.8V and can be set by configuring JU2. See Table 1 for JU2 configuration. VI/O output voltage is fixed to 3.3V and can supply 900mA. SLEEP Mode The EV kit contains a 3-pin jumper (JU1) that can be used to enable the MAX1702B in normal mode or to place it in sleep mode. In normal operation, the three converters are enabled. In sleep mode, VCORE is in shutdown while VI/O and VMEM remain enabled. Sleep mode allows the microprocessor to enter sleep mode while memory and I/O peripherals are kept alive in a system application. See Table 2 for JU1 configuration. Normal and sleep modes can also be controlled with an external device by removing the shunt on JU1 and applying a CMOS logic-level signal to the ON2 pad. Triple Outputs OUTOK Output The MAX1702 EV kit features three (VCORE, VMEM, and VI/O) step-down DC-DC converters that can be set to regulate to different voltages. VCORE can supply 400mA at an output voltage of 1.1V. The VCORE output voltage is set with resistors R5 and R6. Refer to the Setting the Output Voltages section in the MAX1702B The MAX1702 EV kit provides an OUTOK logic output signal to indicate the regulation state of VCORE. A logic low at the OUTOK pad indicates that the VCORE output has dropped to 92.5% of its regulation voltage. A logic high at OUTOK indicates that VCORE is 95.5% of its regulation voltage. _______________________________________________________________________________________ 3 Evaluates: MAX1702B Table 1. VMEM Output Settings (JU2) Evaluates: MAX1702B MAX1702 Evaluation Kit R1 267kΩ 1% VIN 1 3 VIN C9 OPEN R2 90.9kΩ 1% 2 R3 137kΩ 1% C1 4.7µF GND 36 LBO R9 100kΩ 9 18 LBI OUT1 LX1 LBO N.C. OUTOK VIN 2 JU1 ON2 3 INP1 U1 22 1 10 VI/O 4 R11 100kΩ PG1 OUTOK RSO COMP1 ON2 N.C. RSO N.C. VI/O R12 100kΩ MR SW1 FB2 16 MR LX2 6 GND PG2 REF 7 REF REF 5 2 REF 3 1 JU2 4 LX3 PGM3 PG3 8 GND 13 L1 4.7µH R8 22kΩ 35 VIN C20 33pF VI/O C2 10µF C11 OPEN 12 IGND R4 33kΩ 17 25 VIN C5 1000pF C18 33pF 26 R6 14kΩ 1% C12 1µF 27 28 24 23 33 32 N.C. INP3 N.C. 31 COMP3 30 C7 1000pF 14 R5 8.06kΩ 1% L2 4.7µH C3 10µF VCORE C16 OPEN R13 1Ω C17 10µF C13 OPEN CGND C19 33pF L3 4.7µH C6 680pF VMEM C4 10µF C15 OPEN 34 C14 1µF Figure 1. MAX1702 EV Kit Schematic 4 VPLL R7 18kΩ COMP2 21 29 OUT3 C8 0.1µF VIN VI/O 20 MAX1702B INP2 11 15 C10 1µF R10 100kΩ VI/O 19 DBI N.C. N.C. N.C. N.C. IN _______________________________________________________________________________________ MGND MAX1702 Evaluation Kit Evaluates: MAX1702B Figure 2. MAX1702 EV Kit Component Placement Guide— Component Side Figure 3. MAX1702 EV Kit PC Board Layout—Component Side Figure 4. MAX1702 EV Kit PC 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ © 2002 Maxim Integrated Products Printed USA 5 is a registered trademark of Maxim Integrated Products.