EVALUATION KIT AVAILABLE MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters LE AVAILAB _______________General Description The MAX710/MAX711 integrate a step-up DC-DC converter with a linear regulator to provide step-up/down voltage conversion. They are optimized for battery applications where the input varies above and below the regulated output voltage. They have an input range from +1.8V to +11V. Typical efficiency when boosting battery inputs is 85%. The MAX710/MAX711 can be configured for minimum noise or optimum efficiency. Shutdown control turns off the part completely, disconnecting the input from the output (ISHDN = 0.2A). Standby control turns off only the step-up converter and leaves the low-power linear regulator active (IQ = 7A). The MAX710 has a preset 3.3V or 5V output voltage. The MAX711 has an adjustable output that can be set from +2.7V to +5.5V with two resistors. Both devices come in 16-pin narrow SO packages. ________________________Applications Single-Cell, Lithium-Powered Portable Devices Digital Cameras 2- to 4-Cell AA Alkaline Hand-Held Equipment 3.3V and Other Low-Voltage Systems 2-, 3-, and 4-Cell Battery-Powered Equipment Battery-Powered Devices with AC Input Adapters __________Typical Operating Circuit Functional Diagrams C1 N/E LBO LBI+ STBY 3.3V Step-Up/Down Voltage Conversion +1.8V to +11V Input Range Output: 5V/250mA at VIN = 1.8V 5V/500mA at VIN = 3.6V No External FETs Required Load Disconnected from Input in Shutdown Battery Drain: 200A No-Load (V IN = 4V) 7A in Standby 0.2A when Off Low-Noise and High-Efficiency Modes ______________Ordering Information PART MAX710C/D MAX710ESE MAX711C/D MAX711ESE TEMP. RANGE 0C to +70C -40C to +85C 0C to +70C -40C to +85C PIN-PACKAGE Dice 16 Narrow SO Dice 16 Narrow SO __________________Pin Configuration TOP VIEW +1.8V TO +11V INPUT ON ____________________________Features OFF SHDN ON MAX710 L1 C2 PS OUTPUT 3.3V/5V OUT C4 REF PGND GND ILIM STBY 5 MAX710 MAX711 13 REF 12 PS 3/5 (FB) 6 11 LBI+ N/E 7 10 LBI- LBO 8 9 C3 0.1F Pin Configurations appear at end of data sheet. Functional Diagrams continued at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. 14 GND ILIM 3 SHDN 4 3/5 LBI- 15 PGND PGND 2 LX STBY 5V 16 LX LX 1 OUT SO ( ) IS FOR THE MAX711. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com. 19-1254; Rev 0; 7/97 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters ABSOLUTE MAXIMUM RATINGS PS, LX, OUT to GND............................................-0.3V to +11.5V ILIM, SHDN, STBY, FB, 3/5, N/E, LBO, LBI-, LBI+, REF to GND ...........................-0.3V to (VPS + 0.3V) PGND to GND .......................................................-0.3V to +0.3V REF Short Circuit to GND ...........................................Continuous IOUT ...................................................................................700mA Continuous Power Dissipation (TA = +70C) SO (derate 8.70mW/C above +70C) ..........................696mW Operating Temperature Range ...........................-40C to +85C Storage Temperature Range .............................-65C to +160C Junction Temperature ......................................................+150C Lead Temperature (soldering, 10sec) .............................+300C Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VPS = 5.6V, STBY = PS, CREF = 0.1F, COUT = 4.7F, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER Input Voltage CONDITIONS MIN MAX 1.8 11.0 N/E = GND (Note 2) 1.8 7.0 Full Load Start-Up Voltage Output Voltage (MAX710) TYP N/E = PS 0.9 TA = 0C to +85C 4.8 5.0 5.2 4.6 5.0 5.3 3/5 = high, IOUT = 0 to 250mA, VPS = 4.7V TA = 0C to +85C 3.17 3.3 3.43 3.05 3.3 3.55 TA = -40C to +85C MAX711 Output Voltage Load Regulation 0 < IOUT < 250mA, STBY = PS 0.5 % STBY = PS, 1.8V to 5V 0.3 %/V V STBY = V SHDN = logic high, current measured into PS pin; ILOAD = 0 100 140 A 7 16 A A Quiescent Current Standby Quiescent Current Shutdown Quiescent Current Reference Voltage Standby Output Current V STBY = 0V V SHDN = 0V TA = 0C to +85C, IREF = 0 TA = -40C to +85C, IREF = 0 5.5 V Output Voltage-Adjustment Range Output Voltage Line Regulation FB V V 3/5 = low, IOUT = 0 to 250mA TA = -40C to +85C UNITS 0.1 5 1.24 1.28 1.31 1.23 1.28 1.32 1.20 1.25 1.29 1.18 1.25 1.31 0.1 1 % nA V STBY = 0V, linear regulator TA = 0C to +85C 10 FB Voltage MAX711, OUT = FB Load Regulation MAX711, OUT = FB FB Input Current FB = 1.25V 1 50 VPS = 5.6V 0.2 0.6 MAX710, VPS = 3.7V 0.3 0.9 MAX711, VPS = 2.7V 0.6 1.2 VLX = 5.6V 0.1 1 LX On-Resistance LX Leakage Current LX Current Limit 2 TA = -40C to +85C V 0mA ILOAD 250mA V mA mV A ILIM = PS 0.5 0.8 1.3 ILIM = GND 1.1 1.5 1.95 A Maxim Integrated MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters ELECTRICAL CHARACTERISTICS (continued) (VPS = 5.6V, STBY = PS, CREF = 0.1F, COUT = 4.7F, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER Output PFET Resistance Output PFET Leakage Thermal Shutdown Thermal Shutdown Hysteresis CONDITIONS MIN TYP MAX 0.7 1.3 MAX710, VOUT = 3.0V 1.3 2.4 MAX711, VOUT = 2.7V 1.6 3.0 VPS = 3V, VOUT = 0V 0.4 3 STBY = PS 150 C STBY = PS 20 C VOUT = 5.0V UNITS A LOGIC Input Low Voltage Input High Voltage Input Bias Current STBY, SHDN, N/E, 3/5, ILIM STBY, SHDN, N/E, 3/5, ILIM 0.4 1.6 V 1 STBY, SHDN, N/E, 3/5, ILIM V 50 nA 10 V LBI/LBO COMPARATOR Input Range LBI-, LBI+ (Note 3) Input Bias Current LBI-, LBI+ VLBI-, VLBI+ = 1.25V Hysteresis LBI/LBO Offset Voltage LBO Output Voltage VLBI- = 1.25V ILBO = 2mA, VLBI- = 1.25V, VLBI+ = 1V ILBO = -300A, VLBI- = 1.25V, VLBI+ = 2V 1.2 6 1 50 nA 40 100 mV +25 mV -25 0.4 VPS - 0.2V V Note 1: Specifications at -40C are guaranteed by design, not production tested. Note 2: Guaranteed by design (see Table 1). Note 3: The LBO comparator provides the correct result as long as one input is within the specified input range. Maxim Integrated 3 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters __________________________________________Typical Operating Characteristics (TA = +25C, unless otherwise noted.) VIN = 2.5V VIN = 1.8V VIN = 1V 60 VIN = 1.8V 70 VIN = 1V 50 0.1 1 10 100 1000 0 0.1 1 10 100 VOUT = 5V N/E = PS 0.2 1000 0 50 100 150 200 250 NO-LOAD BATTERY CURRENT vs. INPUT VOLTAGE 70 N/E = PS HIGH-EFFICIENCY MODE ILIM = 0.8A ILIM = 1.5A 80 ILIM = 0.8A 70 ILIM = 1.5A VOUT = 3.3V VIN = 2.5V 50 1 10 100 1000 1200 1000 800 ILIM = GND (1.5A) 600 400 200 ILIM = PS (0.8A) 0 0.1 1 10 100 0 1000 2 4 6 8 10 LOAD CURRENT (mA) LOAD CURRENT (mA) INPUT VOLTAGE (V) MAXIMUM OUTPUT CURRENT vs. INPUT VOLTAGE LINEAR-REGULATOR POWER-SUPPLY REJECTION RATIO vs. FREQUENCY SHUTDOWN CURRENT vs. INPUT VOLTAGE 50 45 PSRR (dB) ILIM = PS 100 40 35 30 25 1.2 1.4 1.6 1.8 2.0 INPUT VOLTAGE (V) N/E = GND 20 N/E = PS 15 2.2 2.4 2.6 10 1.0 12 MAX710/711 TOC09 55 SHUTDOWN CURRENT (A) 60 MAX710/711 TOC08 ILIM = GND MAX710/711 TOC07 1000 1.0 N/E = GND 1400 LOW-NOISE MODE 60 VOUT = 5V VIN = 2.5V 0.1 1600 SUPPLY CURRENT (A) ILIM = 0.8A ILIM = 1.5A 90 MAX710/711 TOC05 EFFICIENCY vs. LOAD CURRENT-- HIGH-EFFICIENCY AND LOW-NOISE MODES (VOUT = 3.3V) EFFICIENCY (%) EFFICIENCY (%) 0.6 EFFICIENCY vs. LOAD CURRENT-- HIGH-EFFICIENCY AND LOW-NOISE MODES (VOUT = 5V) 60 MAXIMUM OUTPUT CURRENT (mA) 0.8 LOAD CURRENT (mA) 80 4 1.0 OUTPUT CURRENT (mA) N/E = GND 10 1.2 OUTPUT CURRENT (mA) 90 50 1.4 0.4 VOUT = 3.3V N/E = GND MAX710/711 TOC04 50 1.6 60 VOUT = 5V N/E = GND MAX710/711 TOC03 80 1.8 INPUT VOLTAGE (V) VIN = 3.6V 70 VIN = 2.5V EFFICIENCY (%) 80 2.0 MAX710/711 TOC02 VIN = 5.6V EFFICIENCY (%) 90 MAX710/711 TOC01 90 MINIMUM START-UP INPUT VOLTAGE vs. LOAD CURRENT MAX710/711 TOC06 EFFICIENCY vs. OUTPUT CURRENT-- HIGH-EFFICIENCY MODE (VOUT = 3.3V) EFFICIENCY vs. OUTPUT CURRENT-- HIGH-EFFICIENCY MODE (VOUT = 5V) 0.8 0.6 0.4 0.2 0 0.01 0.1 1 10 FREQUENCY (kHz) 100 1000 1 2 3 4 5 6 7 8 9 10 11 INPUT VOLTAGE (V) Maxim Integrated MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters ____________________________Typical Operating Characteristics (continued) (TA = +25C, unless otherwise noted.) LINE-TRANSIENT RESPONSE LOAD-TRANSIENT RESPONSE MAX710/711 TOC10 MAX710/711 TOC11 A A B B 2ms/div 1ms/div A: VOUT = 3.3V (50mV/div, AC COUPLED), N/E = PS B: IOUT = 10mA TO 100mA A: VOUT = 3.3V (100mV/div, AC COUPLED), N/E = GND B: VIN = 2V TO 4V, IOUT = 100mA OUTPUT RIPPLE (LOW-NOISE MODE) OUTPUT RIPPLE (HIGH-EFFICIENCY MODE) MAX710/711 TOC13 MAX710/711 TOC12 200s/div 200s/div VIN = 2.5V, IOUT = 20mA, N/E = PS VOUT = 5V (20mV/div, AC COUPLED), IOUT = 20mA VIN = 2.5V, IOUT = 20mA, N/E = GND VOUT = 5V (20mV/div, AC COUPLED), IOUT = 20mA START-UP DELAY TURN-OFF DELAY MAX710/711 TOC14 20s/div A: VOUT (2V/div), IOUT = 100mA B: VSHDN (2V/div) Maxim Integrated MAX710/711 TOC15 A A B B 200s/div A: VOUT (2V/div), IOUT = 100mA B: VSHDN (2V/div) 5 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters ______________________________________________________________Pin Description PIN NAME FUNCTION MAX710 MAX711 1 1 LX 2 2 PGND 3 3 ILIM 4 4 SHDN Shutdown Input. When low, the entire circuit is off and OUT is actively pulled to GND. 5 5 STBY Standby Input. Connect to GND to disable boost circuit. Connect to PS for normal operation. Drain Connection for internal N-channel power MOSFET Power Ground Inductor Current-Limit-Select Input. Connect to GND for 1.5A limit and to PS for 0.8A limit. 6 -- 3/5 Selects the output voltage. Connect to GND for 5V output and to OUT for 3.3V output. -- 6 FB Feedback Input 7 7 N/E Selects low-noise or high-efficiency mode. Connect to GND for high efficiency and to PS for lowest noise. See Operating Configurations section. 8 8 LBO Low-Battery Comparator Output 9 9 OUT Linear-Regulator Output. Bypass with a 4.7F capacitor to GND. 10 10 LBI- Negative Input to Low-Battery Comparator 11 11 LBI+ Positive Input to Low-Battery Comparator 12 12 PS 13 13 REF 1.28V Reference Voltage Output. Bypass with a 0.1F capacitor to GND. 14 14 GND Analog Ground. Must be low impedance. Solder directly to ground plane. 15 15 PGND 16 16 LX Source of internal PFET regulator. The IC is powered from PS. Power Ground Drain Connection for internal N-channel power MOSFET _______________Detailed Description The MAX710/MAX711 integrate a step-up DC-DC converter with a linear regulator to provide step-up/down voltage conversion. The step-up switch-mode regulator contains an N-channel power MOSFET switch. It also shares a precision voltage reference with a linear regulator that contains a P-channel MOSFET pass element (Figure 1). Step-Up Operation A pulse-frequency-modulation (PFM) control scheme with a constant 1s off-time and variable on-time controls the N-channel MOSFET switch. The N-channel switch turns off when the part reaches the peak current limit or the 4s maximum on-time. The ripple frequency is a function of load current and input voltage. Step-Down Operation The low-dropout linear regulator consists of a reference, an error amplifier, and a P-channel MOSFET. The reference is connected to the error amplifier's inverting 6 input. The error amplifier compares this reference with the selected feedback voltage and amplifies the difference. The difference is conditioned and applied to the P-channel pass transistor's gate. Operating Configurations The MAX710/MAX711 have several operating configurations to minimize noise and optimize efficiency for different input voltage ranges. These configurations are accomplished via the N/E input, which controls operation of the on-chip linear regulator. With N/E low, the linear regulator behaves as a 0.7 (at 5V output) PFET switch when the IC is boosting, and as a conventional linear regulator when VIN > VOUT. This provides optimum boost efficiency, but the PFET does little to reject boost-converter output ripple. With N/E high, boost ripple rejection is optimized by maintaining headroom (VFV, typically 0.5V at 5V output) across the linear regulator. Boost mode efficiency is then about 10% lower than with N/E high. Maxim Integrated MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters N/E VOUT VIN ERROR AMP2 REF1 PS LX tON FIXED tOFF GENERATOR VFV DRV N OFF PS ILIM MAX710 100mV CURRENTLIMIT COMPARATOR PGND ERROR AMP1 REF1 PGND PS REF2 OUT (FB) SHDN REFA REF2 REF STBY 3.3/5 REFB LBI+ REF1 GND LBILBO ( ) IS FOR MAX711. Figure 1. Functional Diagram Maxim Integrated 7 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters In high-efficiency mode (N/E = low), the maximum input voltage is limited to 7V. This voltage limitation is easily overcome, however, by configuring the LBO output to change modes based on input voltage, allowing an 11V maximum input with high-efficiency configurations. Four operating configurations are described in Table 1 and in the following subsections. Configuration 1: High Efficiency, 7V Max VIN With N/E connected to GND, when the IC boosts, the linear regulator operates only as a switch, with minimum forward drop, until VIN > VOUT (where linear regulation begins). This configuration is limited to no more than 7V input, but provides best efficiency for batteryonly operation or low-voltage AC adapter usage. Table 1. Operating Configurations Configuration 2: High Efficiency, VBATT < VOUT In this configuration, N/E is driven high by LBO when V IN > V OUT (Figure 2a). When V IN < V OUT , the IC boosts, and the linear regulator operates as a switch, with minimum forward drop. When VIN > VOUT, the linear regulator operates with VFV forward drop, while VPS increases by VFV so that OUT maintains regulation. VFV is set inside the IC to approximately 0.5V (at 5V VOUT). When VIN is only slightly higher than VOUT, conversion efficiency is poorer than in configuration 1, so configuration 2 is most suitable when the battery voltage is less than VOUT, but the AC adapter output is greater than VOUT. NO. DESCRIPTION INPUT VOLTAGE CONNECTIONS 1 High efficiency, 7V max VIN Up to 7V N/E = GND 2 High efficiency, VBATT < VOUT (Figure 2a) Up to 11V LBO = N/E LBI- = VOUT LBI+ = VIN 3 High efficiency, 11V, VBATT < 6.5V (Figure 2b) Up to 11V LBO = N/E LBI- = REF LBI+ = R5, R6 4 Low noise Up to 11V N/E = PS VIN = +1.8V TO +11V VIN = +1.8V TO +11V 100F 100F L1 SHDN LX STBY PS LBO 100F OUT N/E L1 R5 4.7F MAX710 LX STBY PS 100F OUT N/E LBO 4.7F MAX710 LBI+ LBI+ LBI- R6 REF PGND GND ILIM Figure 2a. High-Efficiency Operating Configuration for VBATT < VOUT LBIREF 3/5 0.1F 8 SHDN 0.1F 3/5 PGND GND ILIM (VIN - VREF) VREF R5 = R6 (4.08) WHEN VREF = 1.28V AND VIN = 6.5V R5 = R6 Figure 2b. High-Efficiency Operating Configuration for VBATT < 6.5V Maxim Integrated MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters Configuration 3: High Efficiency, 11V, VBATT < 6.5V In this configuration, N/E is driven high by LBO when V IN > 6.5V (Figure 2b). When V IN < V OUT , the IC boosts, and the linear regulator operates as a switch, with minimum forward drop. When VIN > VOUT, linear regulation begins. When VIN > 6.5V (set by R5 and R6), the linear regulator forces a minimum forward drop of VFV (typically 0.5V at 5V VOUT) as LBO drives N/E high. This transition is not seen at the output, since the linear regulator already has an input-output voltage difference of 6.5V - 5V. Efficiency with VIN slightly higher than VOUT is equal to that of configuration 1, so configuration 3 is most suitable when the battery voltage may be near VOUT. This hookup has no functional shortcomings compared with configuration 2, except that two additional resistors (R5 and R6) are needed. Configuration 4: Low Noise With N/E connected to PS, when the IC is boosting, the linear regulator operates with VFV forward voltage (typically 0.5V at 5V VOUT) for optimum noise rejection. Linear regulation occurs when VIN > VOUT + VFV. The VFV voltage differential results in boost efficiency typically 10% lower than with the high-efficiency configurations. ILIM The current-limit-select input, ILIM, selects between the two peak current limits: 1.5A (ILIM = GND) and 0.8A (ILIM = PS). If the application requires 200mA or less from the MAX710/MAX711, select 0.8A. The lower peak current limit permits the use of smaller, low-cost inductors. The ILIM input is internally diode clamped to GND and PS, and should not be connected to signals outside this range. Shutdown and Standby Modes Grounding SHDN turns off the MAX710/MAX711 completely, disconnecting the input from the output. Tie SHDN to PS for normal operation. The MAX710/MAX711 have a standby mode that shuts down the step-up converter. The linear regulator remains on with a 7A (typ) LDO quiescent current. Connect STBY to ground to enter standby mode; otherwise, connect STBY to PS. __________________Design Procedure Output Voltage Selection For the MAX710, you can obtain a 3.3V or 5V output voltage by tying 3/5 to GND or PS. Efficiency is typically 85% over a 2mA to 250mA load range. The device is bootstrapped, with power derived from the step-up voltage output (at PS). Under all load conditions, the Maxim Integrated IN C1 L1 ON R3 OFF SHDN LX STBY PS OUT N/E LBO R1 MAX711 LBI+ R4 C2 C4 FB LBI- R2 REF PGND GND ILIM Figure 3. MAX711 Adjustable Output Voltage MAX710/MAX711 typically start up with a 1V input. If the battery voltage exceeds the programmed output voltage, the output will linear regulate down to the selected output voltage. The MAX711's adjustable output voltage is set by two resistors, R1 and R2 (Figure 3), which form a voltage divider between the output and FB. Use the following equation to determine the resistor values: R1 = R2 [(VOUT / VREF) - 1] where VREF = 1.25V. Since the input bias current at FB has a maximum value of 50nA, R1 and R2 can be large with no significant accuracy loss. Choose R2 in the 100k to 1M range and calculate R1 using the formula above. For 1% error, the current through R1 should be at least 100 times FB's bias current. Low-Battery Comparator The MAX710/MAX711 contain a comparator for lowbattery detection. If the voltage at LBI+ falls below that at LBI- (typically connected to REF), LBO goes low. Hysteresis is typically 50mV. Set the low-battery monitor's threshold with two resistors, R3 and R4 (Figure 2), using the following equation: R3 = R4 [(VLBT / VLBI-) - 1] 9 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters Table 2. Component Selection INDUCTORS (L1) CAPACITORS RECTIFIERS (D1) Sumida CD75-220 (1.5A), CDRH-74-220 (1.23A), or CD54-220 100F, 16V low-ESR tantalum capacitor AVX TPSE107M016R0100 or Sprague 593D107X0016E2W Coilcraft DO33-08P-223 4.7F, 16V tantalum capacitor Sprague 595D475X0016A2T where VLBT is the desired threshold of the low-battery detector and VLBI- is the voltage applied to the inverting input of the low-battery comparator. Since LBI current is less than 50nA, R3 and R4 can be large (typically 100k to 1M), minimizing input supply loading. If the low-battery comparator is not used, connect LBI+ to PS and LBI- to REF, leaving LBO unconnected. Inductor Selection A 22H inductor value performs well in most MAX710/MAX711 applications. The inductance value is not critical, however, since the MAX710/MAX711 work with inductors in the 18H to 100H range. Smaller inductance values typically offer a smaller size for a given series resistance, allowing the smallest overall circuit dimensions. Circuits using larger inductance values exhibit higher output current capability and larger physical dimensions for a given series resistance. The inductor's incremental saturation current rating should be greater than the peak switch-current limit, which is 1.5A for ILIM = GND and 0.8A for ILIM = PS. However, it is generally acceptable to bias most inductors into saturation by as much as 20%, although this slightly reduces efficiency. The inductor's DC resistance significantly affects efficiency. See Tables 2 and 3 for a list of suggested inductors and suppliers. Capacitor Selection A 100F, 16V, 0.1 equivalent series resistance (ESR), surface-mount tantalum (SMT) output filter capacitor, C2, typically exhibits 50mV output ripple when stepping up from 2V to 5V at 100mA. Smaller capacitors (down to 10F with higher ESRs) are acceptable for light loads or in applications that can tolerate higher output ripple. The ESR of both bypass and filter capacitors affects efficiency and output ripple. Output voltage ripple is the product of the peak inductor current and the output capacitor's ESR. Use low-ESR capacitors for best performance, or connect two or more filter capacitors in parallel. Low-ESR, SMT capacitors are currently available from Sprague (595D series) and AVX (TPS series). Sanyo OS-CON organic-semiconductor through-hole capacitors also exhibit very low ESR and are especially 10 Schottky diode Motorola MBRS130T3 useful for operation at cold temperatures. The output capacitor, C3, needs to be only 4.7F to maintain linear regulator stability. See Tables 2 and 3 for a list of suggested capacitors and suppliers. Rectifier Diode For optimum performance, use a switching Schottky diode. Refer to Tables 2 and 3 for the suggested diode and supplier. __________Applications Information The MAX710/MAX711 high-frequency operation makes PC layout important for minimizing ground bounce and noise. Keep the IC's GND pin and the ground leads of C1 and C2 (Figure 1) less than 0.2in. (5mm) apart. Also keep all connections to the FB and LX pins as short as possible. To maximize output power and efficiency and minimize output ripple voltage, use a ground plane and solder the IC's GND pin directly to the ground plane. Table 3. Component Suppliers SUPPLIER PHONE FAX AVX (803) 946-0690 (803) 626-3123 Coilcraft (847) 639-6400 (847) 639-1469 Motorola (602) 303-5454 (602) 994-6430 Sanyo (619) 661-6835 (619) 661-1055 Sprague (603) 224-1961 (603) 224-1430 Sumida (847) 956-0666 (847) 956-0702 ___________________Chip Information TRANSISTOR COUNT: 661 SUBSTRATE CONNECTED TO GND Maxim Integrated MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters SOICN.EPS ________________________________________________________Package Information Maxim Integrated 11 MAX710/MAX711 3.3V/5V or Adjustable, Step-Up/Down DC-DC Converters NOTES 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. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. 12 (c) Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 Maxim Integrated The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc. Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: MAX710ESE+ MAX711ESE+ MAX710ESE+T MAX711ESE+T MAX710ESE-T MAX711ESE MAX711ESE-T MAX710ESE