MAX8855 MAXIM [Maxim Integrated Products], MAX8855 Datasheet
MAX8855
Related parts for MAX8855
MAX8855 Summary of contents
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... V ideal for on-board point-of-load applications. Total output error is less than ±1% over load, line, and temperature. The MAX8855 operates in PWM mode with a switching frequency ranging from 0.5MHz to 2MHz, set by an external resistor. It can also be synchronized to an external clock in the same frequency range. Two inter- nal switching regulators operate 180° ...
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Dual, 5A, 2MHz Step-Down Regulator ABSOLUTE MAXIMUM RATINGS IN_, LX_ VDL, PWRGD_ to GND..................-0.3V to +4. VDL to IN_.....................................................-0.3V to +4.5V DD EN_, SS_, COMP_, FB_, REFIN, FSYNC to GND ......-0.3V to the lower of ...
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Dual, 5A, 2MHz Step-Down Regulator ELECTRICAL CHARACTERISTICS (continued 3.3V 0.5V VDD VDL FB 0.022µF, PWRGD not connected -40°C to +85°C, typical values are PARAMETER REFIN, ...
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... PWRGD_ Leakage Current Note 2: All devices 100% production tested at +25°C. Limits over temperature are guaranteed by design. Note 3: V must equal V and be equal to or greater than V VDD VDL ( 3.3V. MAX8855, circuit of Figure 6, T IN1 IN2 EFFICIENCY vs. LOAD CURRENT WITH 3.3V INPUT 100 ...
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... Dual, 5A, 2MHz Step-Down Regulator ( 3.3V. MAX8855, circuit of Figure 6, T IN1 IN2 SWITCHING FREQUENCY vs. TEMPERATURE 1100 1080 1060 1040 1020 1000 980 960 940 920 900 -40 -15 10 AMBIENT TEMPERATURE (°C) SHUTDOWN SUPPLY CURRENT vs. SUPPLY VOLTAGE IN1 IN2 VDL VDD ...
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... Dual, 5A, 2MHz Step-Down Regulator ( 3.3V. MAX8855, circuit of Figure 6, T IN1 IN2 OUTPUT PEAK CURRENT LIMIT vs. OUTPUT VOLTAGE 0.8 1.1 1.4 1.7 2.0 2.3 2.6 OUTPUT VOLTAGE (V) OUTPUT TRACKING (EN1 = EN2) V OUT1 V OUT2 V PWRGD1 V PWRGD2 1ms/div DDR TRACKING 1.8V, 0.9V 6 _______________________________________________________________________________________ Typical Operating Characteristics (continued) = +25°C, unless otherwise noted.) ...
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Dual, 5A, 2MHz Step-Down Regulator PIN NAME Power-Good Open-Drain Output for Regulator 1. PWRGD1 is high impedance when V ≥ 0 PWRGD1 V FB1 REFIN thermal shutdown is activated, or when V External Reference Input for Regulator ...
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... Figure 1 shows the MAX8855 functional diagram. The MAX8855 provides both peak and valley current limits to achieve robust short-circuit protection. During the high-side MOSFET’s on-time, if the drain-source current reaches the peak current-limit threshold (specified in ...
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... REFIN - FB1 ERROR AMPLIFIER COMP1 COMP LOW DETECTOR FROM SS2 (0.6V FB2 ERROR AMPLIFIER COMP2 COMP LOW DETECTOR THERMAL REF SHUTDOWN MAX8855 Figure 1. Functional Diagram _______________________________________________________________________________________ _______________________________________________________________________________________ CURRENT-LIMIT COMPARATOR UVLO DC CIRCUITRY + IN2 VDD IN1 CONTROL LOGIC EN1 REF CLOCK THERMAL SHUTDOWN1 CURRENT-LIMIT ...
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... EN_ low turns the regulator off. Driving both EN1 and EN2 low puts the IC in low-power shutdown mode, reducing the supply current typically to 30nA. The MAX8855 regula- tors power up when the following conditions are met (see Figure 2): • ...
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Dual, 5A, 2MHz Step-Down Regulator For ratiometric tracking applications, connect REFIN to the center of a voltage-divider from the output of regula- tor 2 to GND (see Figure 3b). In this application, the EN_ inputs are connected to each other ...
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... SS 2 OUT 2 Synchronization (FSYNC) The MAX8855 operates from 500kHz to 2MHz using either its internal oscillator externally supplied clock. See the Setting the Switching Frequency section. Thermal-Overload Protection Thermal-overload protection limits the total power dissi- pation of the MAX8855. Internal thermal sensors monitor the junction temperature at each of the regulators. When the junction temperature exceeds +165° ...
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... S The MAX8855 can also be synchronized to an external clock from 500kHz to 2MHz by connecting the clock signal to FSYNC through a 10kΩ isolation resistor. The external sync frequency must be higher than the fre- quency that would be produced by R regulators switch at the same frequency as the FSYNC clock, and are 180° ...
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... ESR in the above equation is equal to that of the ESR of a single-output capacitor divided by the total number of output capacitors. The high-switching-frequency range of the MAX8855 allows the use of ceramic output capacitors. Since the ESR of ceramic capacitors is typically very low, the fre- ...
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Dual, 5A, 2MHz Step-Down Regulator π × × π × × π × ...
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... Use caution when routing feedback and compensa- tion node traces; avoid routing near high dV/dt nodes (LX_) and high-current paths. Place the feed- back and compensation components as close as possible to the IC pins. • Reference the MAX8855 Evaluation Kit for an exam- ple layout. ...
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... V C16 R11 C8 DD 0.1µF 10Ω 0.22µF V VDL DD IN1 IN2 PGND1 PGND2 BST1 BST2 C6 LX1 LX2 GND MAX8855 COMP1 COMP2 FB1 FB2 REFIN SS2 SS1 FSYNC PWRGD1 PWRGD2 EN1 EN2 EXPOSED PAD C2 C23 0.1µF 10µF C19 C20 L2 22µF 0.1µF OUT2 C17 0.56µ ...
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... Figure 7. Tracking DDR Application Circuit 18 ______________________________________________________________________________________ V C16 R11 C8 DD 0.1µF 10Ω 0.22µF V VDL DD IN1 IN2 PGND1 PGND2 BST1 BST2 C6 LX1 LX2 GND MAX8855 COMP1 COMP2 FB1 FB2 REFIN C7 SS2 1000pF SS1 FSYNC PWRGD1 PWRGD2 EN1 EN2 EXPOSED PAD C2 C23 0.1µF 10µF C19 C20 L2 22µF 0.1µ ...
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... Dual, 5A, 2MHz Step-Down Regulator Pin Configuration TOP VIEW PGND1 25 PGND1 26 27 IN1 28 IN1 MAX8855 EN1 29 COMP1 30 31 FB1 + 32 SS1 THIN QFN (5mm x 5mm) ______________________________________________________________________________________ PROCESS: BiCMOS PGND2 15 PGND2 14 IN2 13 IN2 12 EN2 COMP2 11 10 FB2 ...
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Dual, 5A, 2MHz Step-Down Regulator (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 20 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN ...
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Dual, 5A, 2MHz Step-Down Regulator (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) Maxim cannot assume responsibility for use of any circuitry other than circuitry ...