MAX1887EEE Maxim Integrated Products, MAX1887EEE Datasheet
MAX1887EEE
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... I o 20µA Standby Supply Current o <1µA Shutdown (MAX1897) Supply Current o Small 16-Pin QSOP (MAX1887), Compact 20-Pin 5mm x 5mm QFN (MAX1897), or 20-Pin 5mm x 5mm Thin QFN (MAX1897) PART MAX1887EEE GP* MAX1897ETP *Contact factory for availability. TOP VIEW Applications ) Converters Pin Configurations continued at end of data sheet. ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +30V GND (Note 3) .......................................-0. PGND to GND.....................................................................±0.3V TRIG, LIMIT to GND .................................................-0.3V to +6V SHDN to ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V (MAX1897 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER SYMBOL CURRENT SENSING On-Time Adjustment Range COMP Output Current I ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V (MAX1897 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER SYMBOL LOGIC Logic ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V (MAX1897 -40°C to +85°C, unless otherwise noted.) (Note 5) A PARAMETER SYMBOL Shutdown Supply Current ( (MAX1897, Note 3) CURRENT SENSING On-Time Adjustment Range ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies (Circuit of Figure 12V TWO-PHASE EFFICIENCY vs. LOAD CURRENT (V = 1.3V) OUT 100 ...
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Figure 12V COMPENSATION OUTPUT CURRENT vs. CURRENT-SENSE VOLTAGE DIFFERENTIAL 100 OUT = CM+ = CM COMP M CS+ CS- 60 ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies (Circuit of Figure 12V SWITCHING WAVEFORMS (OUT-OF-PHASE) 20A 10V 0 1µs/div A. OUTPUT VOLTAGE MASTER/SLAVE INDUCTOR CURRENTS C. MASTER/SLAVE LX WAVEFORMS ...
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Figure 12V DYNAMIC OUTPUT VOLTAGE TRANSITION 5.0V 0 1.3V 1. 40µs/div A. ZMODE = OUTPUT VOLTAGE 1.10V (ZMODE = V C. SLAVE ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies PIN NAME MAX1887 MAX1897 1 19 ILIM 2 20 TRIG CM- — 3 TON COMP — 7 POL 8 8 ...
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PIN NAME MAX1887 MAX1897 BST LIMIT Table 1. Component Selection for Standard Applications COMPONENT CIRCUIT OF FIGURE 1 Output Voltage Input Voltage Range Maximum Load Current Inductor ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies Table 2. Component Suppliers MANUFACTURER MOSFETS Fairchild Semiconductor International Rectifier Siliconix CAPACITORS Kemet Panasonic Sanyo Taiyo Yuden INDUCTORS Coilcraft Coiltronics Sumida transition on the TRIG input, the slave controller’s inductor current is below ...
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C2 0.22µF TO LOGIC DAC INPUTS SUSPEND INPUTS MUX CONTROL C CC 47pF R13 C REF 0Ω 0.22µF R8 53.6kΩ FLOAT (300kHz) ON OFF R9 100kΩ C5 470pF R10 34.8kΩ 5V BIAS SUPPLY C3 R7 1µF 10Ω C4 0.22µF FLOAT ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies ( CONTROLLER (SHDN)* BIAS (TON)* V+ COMP CS- GMS CS+ CM+ GMM CM- LIMIT POSITIVE CM LIMIT Figure 2. Functional Diagram η number of phases (1/ ) when compared to a ...
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Therefore, the instantaneous input current peaks of each phase do not overlap, resulting in reduced input and output volt- age ripple and RMS ripple current. This lowers the input and output capacitor requirements, which ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies Table 4. Operating Mode Truth Table SHDN ILIM DL GND X High GND V High CC (< 0.25V) High V Switching CC (> 0.25V Don’t Care Several Quick-PWM converters that may ...
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LIMIT(VALLEY) LOAD(MAX) 0 TIME Figure 3. “Valley” Current-Limit Threshold Point There also is a negative current limit that prevents excessive reverse inductor currents when V ing current. The negative current-limit threshold is set to approximately 150% of ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies MOSFET Gate Drivers (DH, DL) The DH and DL drivers are optimized for driving moder- ately sized, high-side and larger, low-side power MOSFETs. This is consistent with the low duty factor seen in ...
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MOSFET technology that are making higher frequen- cies more practical. Setting Switch On Time: The constant on-time control algorithm in the master results in a nearly constant switching frequency despite the lack of a fixed-frequen- cy clock generator. In ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies SLAVE CONTROLLER R C ILIM R D MAX1887 MAX1897 R LIMIT LIMIT C LIMIT Figure 5. Setting the Adjustable Current Limits current-limit threshold. This is acceptable since the slave’s inductor current limit only ...
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Use 1% toler- ance resistors in the divider with 10µA to 20µA DC bias current to prevent significant errors due to the ILIM pin’s input current. Reducing the current-limit threshold voltage lowers the sense ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies SLAVE CURRENT-LIMIT VOLTAGES vs. AVERAGE INDUCTOR CURRENT 160 140 120 100 AVERAGE INDUCTOR CURRENT (A) MASTER CURRENT-LIMIT VOLTAGES vs. AVERAGE INDUCTOR CURRENT 160 140 120 100 ...
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In non-CPU applications, the output capacitor selection often depends on how much ESR is needed to maintain an acceptable level of output ripple voltage. The output ripple voltage of a step-down controller equals the total inductor ripple current multiplied by ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies Input Capacitor Selection The input capacitor must meet the ripple current requirement (I ) imposed by the switching currents. RMS The MAX1887/MAX1897 multiphase slave controllers operate out-of-phase (MAX1897 POL = V staggering the ...
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V , consider choosing another MOSFET with IN(MAX) lower parasitic capacitance. For the low-side MOSFET (N ), the worst-case power L dissipation always occurs at maximum input voltage: V OUT = sistive ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies VOLTAGE POSITIONING THE OUTPUT 1.4V 1.4V A. CONVENTIONAL CONVERTER (50mV/div) B. VOLTAGE-POSITIONED OUTPUT (50mV/div) Figure 7. Voltage Positioning the Output 50mV x 21.3A = 1.06W, which results in an overall power savings of: ...
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Ceramic Output Capacitor Applications Ceramic capacitors have advantages and disadvan- tages. They have ultra-low ESR and are noncom- bustible, relatively small, and nonpolarized. However, they are also expensive and brittle, and their ultra-low ESR characteristic can result in excessively high ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies MAX1718 (MASTER) MASTER LM VIA TO CM+ AND VIA TO CM MASTER Figure 9. Power-Stage PC Board Layout Example 28 ______________________________________________________________________________________ MAX1897 (SLAVE) VIA TO POWER GROUND ≤10Ω ...
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REF (MASTER) FLOAT (300kHz) ILIM (MASTER) FB (MASTER MAX1897 PINS ONLY V bypass capacitor go; the master’s analog DD ground plane where sensitive analog components, the master’s GND pin and V CC go; and the slave’s analog ground ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 30 ______________________________________________________________________________________ Package Information ...
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For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies Package Information (continued) 31 ...
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Quick-PWM Slave Controllers for Multiphase, Step-Down Supplies (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 32 ______________________________________________________________________________________ Package Information (continued) ...
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... 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 ____________________ 33 © 2002 Maxim Integrated Products ...