19-5533; Rev 0; 11/11 MAX44269 Evaluation Kit Evaluates: MAX44269 General Description The MAX44269 evaluation kit (EV kit) is a fully assembled and tested PCB that evaluates the MAX44269 dual comparator in a 1.3mm x 1.3mm wafer-level package (WLP). The EV kit circuit can be easily configured by installing shunts and changing a few components to support multiple comparator application circuits, such as window detector, jack detection, relaxation oscillator, pulse-width modulated (PWM) generator, logic-level translator, or power-on-reset circuit. The EV kit provides 0603 component PCB pads for ease of evaluation. The EV kit circuit operates from a +1.8V to +5.5V VCC supply. Features S1.8V to 5.5V Input Voltage-Supply Range SConfigurable for: Window Detector Jack Detection Relaxation Oscillator PWM Generator Logic-Level Translator Power-on-Reset Circuit SEvaluates 9-Bump WLP Package SProven PCB Layout SFully Assembled and Tested Ordering Information appears at end of data sheet. Component List DESIGNATION QTY DESCRIPTION 1 4.7FF Q10%, 6.3V X5R ceramic capacitor (0805) Murata GRM21BR60J475K C2 1 0.1FF Q10%, 50V X5R ceramic capacitor (0603) Murata GRM188R71H104k D1, D2 0 Not installed, diodes (0603) GND 4 Small black test points C1 J1, J2 2 3.5mm audio jacks JU1, JU2 2 3-pin headers JU3, JU4, JU5 3 2-pin headers OUTA, OUTB, TP1–TP4, VCC 7 Small red test points DESIGNATION QTY R1, R2, R6–R9, R12, R13, R15 DESCRIPTION 0 Not installed, resistors (0603) R3, R5, R10, R14 4 0I Q5% resistors (0603) R4, R11 2 100kI Q5% resistors (0603) U1 1 Low-power dual comparator ( 9 WLP) Maxim MAX44269EWL+ (Top Mark: +AJL) — 5 Shunts — 1 PCB: MAX44269 EVALUATION KIT Component Supplier SUPPLIER Murata Electronics North America, Inc. PHONE 770-436-1300 WEBSITE www.murata-northamerica.com Note: Indicate that you are using the MAX44269 when contacting this component supplier. __________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX44269 Evaluation Kit Evaluates: MAX44269 • MAX44269 EV kit Quick Start Detailed Description of Hardware Required Equipment The MAX44269 EV kit is a fully assembled and tested PCB that evaluates the MAX44269 open-drain, dual comparator. The EV kit requires a 1.8V to 5.5V input supply voltage at VCC for normal operation. • Three adjustable 0 to 5V DC power supplies • Dual-channel oscilloscope Procedure The EV kit is fully assembled and tested. Follow the steps below to verify board operation. Caution: Do not turn on the power supplies until all connections are completed. 1)Verify that shunts are installed as followed: JU1: JU2: JU3: JU4: JU5: Pins 1-2 Pins 2-3 Installed Not installed Installed 2)Set a DC power supply to 3.3V. Connect the positive terminal of the power supply to the VCC PCB pad and the ground terminal to the GND PCB pad. 3) Set another DC power supply to 2.5V. Connect the positive terminal of the power supply to the IN1+ PCB pad and the ground terminal to the GND PCB pad. 4) Set another DC power supply to 2V. Connect the positive terminal of the power supply to the IN1- PCB pad and the ground terminal to the GND PCB pad. 5) Enable all three DC power supplies. 6) Verify that OUTA and OUTB are at logic-high (3.3V). 7) Increase the IN1- voltage to 3V and verify that OUTA and OUTB are now at logic-low (0V). The EV kit circuit is configured for independent evaluation of comparator A and comparator B. The comparators have rail-to-rail inputs and an internal 4mV hysteresis. Comparator A input signals are applied at the IN1+/ IN1- PCB pads. Resistors R1, R2, and R3 are available to provide additional hysteresis using positive feedback. The comparator output can be monitored at the OUTA test point. Comparator B input signals are applied at the IN2+/IN2- PCB pads. Resistors R8, R9, and R10 are available to provide additional hysteresis using positive feedback. The comparator output can be monitored at the OUTB test point. Refer to the MAX44269 IC data sheet for additional information on adding external hysteresis using the on-board resistors. The EV kit provides various jumpers and 0603 PCB resistor pads, allowing easy configuration for various comparator application circuits such as a window detector, jack detection, relaxation oscillator, power-on-reset, or PWM generator. Jumpers JU1 and JU2 are available to provide flexibility on the number of voltage sources used for driving the comparator inputs. Jumper JU2 (in addition to JU4) can also be used for configuring the EV kit circuit for window detection or PWM generator operation. Jumpers JU3 and JU5 are available for logic-level translation using external voltage sources applied at the VPULLA and VPULLB PCB pads, respectively. Refer to this document for proper jumper configuration when evaluating the various application circuits. Input Configuration Jumpers JU1 and JU2 are provided to allow flexibility for configuring the voltage source for the comparators’ inputs and configuring the inputs for the various comparator applications. See Table 1 for jumper JU1 and JU2 configurations. Table 1. Input Source (JU1, JU2) JUMPER JU1 SHUNT POSITION 1-2* Single source driving noninverting inputs. 2-3 Single source driving IN1+ and IN2- PCB pads. Not installed JU2 EV KIT CONFIGURATION Independent voltage sources driving noninverting inputs. 1-2 Single source driving IN1- and IN2+ PCB pads. 2-3* Single source driving inverting inputs. Not installed Independent voltage source driving inverting inputs. *Default position. __________________________________________________________________ Maxim Integrated Products 2 MAX44269 Evaluation Kit Evaluates: MAX44269 Comparator Application Circuits Logic-Level Translation Jumpers JU3 and JU5 are available to select the output logic voltage for the comparators’ open-drain outputs (Figure 1). Install a shunt at the jumpers to set VCC as the comparator output logic level. Remove the shunt and apply the desired voltage source at the VPULLA and/or VPULLB PCB pads to set the comparator output logic level independent of the supply voltage. Note that the OUTA and OUTB pins have an absolute maximum voltage of -0.3V to 6V. See Table 2 for proper jumper configurations. Jumper JU4 is also provided to connect Comparator A and B outputs together for window-detection operation. See Table 3 for proper JU4 configuration. Jack Detection Each of the EV kit comparators can be configured as a simple jack-detection circuit, as follows: 1) Short the IN1+ (or IN2+) PCB pads to VCC. 2) Install a pullup resistor greater than 1kI at the R3 (or R10) pad to minimize the power dissipated across the resistors when inserting a standard 3-conductor plug at the corresponding jack (J1 or J2). 3) Uninstall jumpers JU1, JU2, and JU4. 4) Apply a suitable external reference voltage at the IN1- (or IN2-) PCB pad. The value of the pullup resistor and the reference voltage can be adjusted to select the threshold voltage for accessory detection. Relaxation Oscillator Comparator A can be configured to operate as a simple relaxation oscillator (Figure 2), as follows: 1) Add a suitable resistor and capacitor at the R7 and R6 pads, respectively. 2) Short IN1+ to VCC. 3) The trip thresholds are set by applying suitable external hysteresis using resistors R1, R2, and R3. 4) Uninstall jumpers JU1, JU2, and JU4. 5) Comparator B can also be independently configured to operate as a relaxation oscillator, as follows: a) Add a suitable resistor and capacitor at the R13 and R12 pads, respectively. b) Short IN2+ to VCC. c) The trip thresholds are set by applying suitable external hysteresis using resistors R8, R9, and R10. d) Uninstall jumpers JU1, JU2, and JU4. VCC VIN SHUNT POSITION OUT_ PIN Installed* Pulled up to VCC through resistors R4/R11 VCC Pulled up to PULLA/ VPULLB through resistors R4/R11 External voltage applied at the VPULLA/VPULLB PCB pads Not installed R4/R11 OUT 5) When no accessory is plugged into the jack (IN_+ > IN_-), the corresponding OUT_ is at logic-high. When the plug is inserted at jack J1 (or J2), the IN_+ voltage falls below IN_-, causing the corresponding OUT_ to trip low. Table 2. OUTA and OUTB Logic Level (JU3, JU5) VPULL MAX44269 VREF GND Figure 1. Logic-Level Translator VCC LOGIC-HIGH VOLTAGE R1/R8 VCC R3/R10 R4/R11 MAX44269 OUT R2/R9 *Default position. GND Table 3. Jumper JU4 Configuration SHUNT POSITION EV KIT CONFIGURATION Installed Window detector Not installed* Normal operation R7/R13 R6/R12 *Default position. Figure 2. Relaxation Oscillator __________________________________________________________________ Maxim Integrated Products 3 MAX44269 Evaluation Kit Evaluates: MAX44269 Use the equations below to determine the optimum component values: COMPARATOR A: R1R2 V T_RISE = VCC R3 R1 + R3 R2 + R1R2 R2 R7 (R3 + R1) + (R1R2) V T_FALL = VCC R2 R7 (R3 + R1) + R1 R2 + R3 (R1 + R1R7 + R7) Using the basic time-domain equations for the charging and discharging of the respective comparator RC circuit, the Comparator A oscillator frequency can be calculated using the equation below: fOSCA = 1 V T_FALL (VIN1+ − VT_RISE ) R7 R6 ln V T_RISE (VIN1+ − V T_FALL) where VIN1+ is in kI, R6 is in FF, and the oscillator frequency is in kHz. COMPARATOR B: R8 R9 V T_RISE = VCC R10 R8 + R10 R9 + R8 R9 R9 R13 (R10 + R8) + (R1R2) V T_FALL = VCC R9 R13 (R10 + R8) + R8 R9 + R10 (R8 + R8 R13 + R13) Resistors R3, R15, and R12 pads are available for setting the overvoltage, and undervoltage-threshold levels. OUTA provides an active-low undervoltage indication and OUTB provides an active-low overvoltage indication. The open-drain outputs of both comparators are wired in an OR configuration using jumper JU4 to give an active-high power-good signal on either OUTA or OUTB. For accurate threshold settings, use the following equations: Select resistor R12’s value so the current through R12 exceeds 1.5FA: R12 = where VIN1- is the reference voltage applied at the IN1or IN2+ PCB pads and R12 is in kI. Choose the desired overvoltage threshold and calculate resistance RT using Equation 1 for resistor R12 value: VOTH RT =× R12 − 1 (Equation 2) VIN1- where RT = R3 + R15 in kI and VOTH is the desired overvoltage threshold in volts. Table 4. Window Detector Jumper Configurations Using the basic time-domain equations for the charging and discharging of the respective comparator RC circuit, the Comparator B oscillator frequency can be calculated using the equation below: fOSCB = VIN1(Equation 1) 1.5µA JUMPER SHUNT POSITION JU1, JU5 Not installed JU2 1-2 JU3, JU4 Installed VCC VIN1+ VCC R3 R4 INA+ 1 OUTA V T_FALL (VINB+ − VT_RISE ) R13 R12 ln V T_RISE (VINB+ − V T_FALL) where VIN2+=VCC, R13 is in kI, R12 is in FF, and the oscillator frequency is in kHz. Window Detector Circuit Table 4 depicts the proper jumper configuration for evaluating the EV kit window detector application circuit (Figure 3) using Comparators A and B. See Table 4 for proper jumper configurations. R15 INA- POWER GOOD MAX44269 INB+ OUTB REF 1.24V INB- GND R12 GND Figure 3. Window Detector Circuit __________________________________________________________________ Maxim Integrated Products 4 MAX44269 Evaluation Kit Evaluates: MAX44269 Calculate R15 using the following equation: VIN1- R15 = (R12 + RT) × − R12 (Equation 3) VUTH Table 5. PWM Generation Circuit Jumper Configuration where VUTH is the desired undervoltage threshold and R15 is in kI. Calculate the R3 resistor value using Equation 3 to obtain R15 value: R3 = RT − R15 JUMPER SHUNT POSITION JU1 Not installed JU2 2-3 JU3, JU5 Installed JU4 Not installed where R3 is in kI. PWM Generator The EV kit can be configured to generate a simple PWM signal using Comparators A and B (Figure 4). See Table 5 for proper jumper configurations on the EV kit for a simple PWM generation circuit. Configure Comparator A as a relaxation oscillator as described in the previous section. Jumper JU2 connects the sawtooth waveform generated on Comparator A’s inverting input to Comparator B’s inverting input. The analog control voltage, applied on the noninverting input of Comparator B (IN2+), determines the pulse width. Note: Since the relaxation oscillator generates a sawtooth waveform, the duty cycle is not a linear function of the applied analog control voltage. Power-On-Reset (POR) Circuit The EV kit can be used to evaluate a POR circuit (Figure 5). R4 VCC VCC R3 R4 OUTA R2 INAR5 R6 ANALOG CONTROL VOLTAGE R11 OUTB Comparator A can be configured as a POR circuit, as follows: GND 1) Short the IN1+ and IN1- PCB pads to the VCC pad. 2) Replace the R5 and R6 pads with suitable resistors to create a resistive-divider between VCC and GND at the comparator’s inverting input. Figure 4. PWM Generator 3) Populate a suitable resistor and capacitor on the R3 and R2 pads, respectively. The RC time constant provides the required power-up delay time at the noninverting input. 4) Diode D1 (optional) can be used to rapidly discharge the capacitor (CR2) in the event of sudden power loss. VCC VCC R3/R10 D1/D2 R5/R14 MAX44269 To configure Comparator B for a POR circuit instead, do the following: 1) Short the IN2+ and IN2- PCB pads to the VCC pad. 2) Replace the R14 and R12 pads with suitable resistors to create a resistive-divider between VCC and GND at the comparator’s inverting input. 3) Populate a suitable resistor and capacitor on the R10 and R9 pads, respectively. The RC time constant provides the required power-up delay time at the noninverting input. VCC MAX44269 R4/R11 OUT_ R2/R9 R6/R12 GND Figure 5. Power-on-Reset Circuit 4) Diode D2 (optional) can be used to rapidly discharge the capacitor (CR9) in the event of sudden power loss. __________________________________________________________________ Maxim Integrated Products 5 MAX44269 Evaluation Kit Evaluates: MAX44269 Figure 6. MAX44269 EV Kit Schematic __________________________________________________________________ Maxim Integrated Products 6 MAX44269 Evaluation Kit Evaluates: MAX44269 1.0” Figure 7. MAX44269 EV Kit Component Placement Guide 1.0” Figure 8. MAX44269 EV Kit PCB Layout—Component Side 1.0” Figure 9. MAX44269 EV Kit PCB Layout—Solder Side __________________________________________________________________ Maxim Integrated Products 7 MAX44269 Evaluation Kit Evaluates: MAX44269 Ordering Information PART TYPE MAX44269EVKIT# EV Kit #Denotes RoHS compliant. __________________________________________________________________ Maxim Integrated Products 8 MAX44269 Evaluation Kit Evaluates: MAX44269 Revision History REVISION NUMBER REVISION DATE 0 11/11 DESCRIPTION Initial release PAGES CHANGED — 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. 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