MAX8554 MAXIM [Maxim Integrated Products], MAX8554 Datasheet
MAX8554
Related parts for MAX8554
MAX8554 Summary of contents
Page 1
... The controllers operate in synchronous-rectification mode to ensure balanced current sourcing and sinking capabili 25A. The MAX8553/MAX8554 also provide up to 95% efficiency, making them ideal for server and point- of-load applications. Additionally, a low 5µA shutdown current allows for longer battery life in notebook applica- tions. Lossless current monitoring is achieved by monitor- ing the low-side MOSFET’ ...
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... MAX8554 enabled EN Input Current HSD Input Voltage Range MAX8554 enabled HSD Input Current REFIN Input Voltage Range V+ Supply Current (MAX8553 Supply Current (MAX8554) V REFIN Supply Current EN/HSD Supply Current VL Supply Current V V+ Shutdown Supply Current EN/HSD = GND REFIN Shutdown Supply Current ...
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... MAX8554 (Note 1) V ±10 +1.25V EN/HSD VTT OUT MAX8554, V ±10 +2.5V, HSD OUT I = 0A, FSEL unconnected OUT 0 < I < +7A +1.25V OUT VTT MAX8554, 0 < I < +7A +2.5V, OUT OUT FSEL unconnected +4.5 to +5.5V REF +5V 50µ REF V ...
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... LX to PGND, R Current-Limit Threshold (Negative LX to PGND, ILIM = VL, with respect to positive Direction) current-limit threshold ILIM Input Current FAULT DETECTION MAX8553 (V Overvoltage Threshold MAX8553 (V MAX8554 VL REGULATOR Output Voltage +6V < V Line Regulation +6V < V RMS Output Current Bypass Capacitor ESR < 100mΩ DRIVER DH Gate-Driver On-Resistance ...
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... EN/HSD Input Voltage Range EN Input Voltage Range EN Input Current HSD Input Voltage Range HSD Input Current REFIN Input Voltage Range V+ Supply Current (MAX8553) V+ Supply Current (MAX8554) REFIN Supply Current EN/HSD Supply Current VL Supply Current V+ Shutdown Supply Current REFIN Shutdown Supply Current VL Shutdown Supply Current ...
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... Ramps the ILIM trip threshold from 20% to 100% in ILIM Ramp Period 20% increments Rising edge of EN/HSD to the start of internal digital Output Predischarge Period soft-start OSCILLATOR MAX8553, V On-Time (Note 2) MAX8554, V On-Time (Note 2) Off-Time (Note 2) CURRENT LIMIT LX to PGND, ILIM = VL Current-Limit Threshold (Positive LX to PGND, R Direction) ...
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... LX DL high state DL low state FSEL = REF FSEL unconnected FSEL = VL Max I for V < +0. EN/HSD EN/HSD +4.5 to +5.5V, 100mV hysteresis +4.5 to +5. MAX8553 MAX8553 MAX8554 MAX8554 I = 2mA SINK V = +5V POK = 1µ 0.22µ ILIM = VL, PGND REF FSEL MIN MAX 2.5 3.0 1. 0.5 1.65 2.35 3.15 3. ...
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... LOAD CURRENT (A) SWITCHING FREQUENCY vs. OUTPUT CURRENT (CIRCUIT OF FIGURE 2) 650 600 550 500 450 400 - OUTPUT CURRENT (A) MAX8554 SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 HSD GND INPUT VOLTAGE (V) LOAD REGULATION (CIRCUIT OF FIGURE 2) 1.31 1.29 VTT CONNECTED 1.27 TO THE OUTPUT 1 ...
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Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications (V = 12V 1.8V, circuit of Figure OUT LOAD TRANSIENT 0A TO 20A TO 0A (CIRCUIT OF FIGURE 1) I OUT ...
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Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications (V = 12V 1.8V, circuit of Figure V+ OUT POWER-UP WAVEFORMS WITH 20A LOAD (CIRCUIT OF FIGURE OUT V POK ...
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... Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications PIN MAX8553 MAX8554 Enable/High-Side Drain. Connect to the high-side N-channel MOSFET drain through a 5.1kΩ EN/HSD — resistor for normal operation. Connect to GND for low-power shutdown (Figure 2). If the enable 1 function is not used, connect EN/HSD directly to the high-side N-channel MOSFET drain ...
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Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications FSEL ON-TIME COMPUTE TON TRIG Q ONE-SHOT POK VTTR VTT POK REFIN EN/HSD 60% 56% 50% 44% MAX8553 12 ______________________________________________________________________________________ VTT Q TRIG ONE-SHOT S Q ...
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... Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications FSEL ON-TIME COMPUTE TON TRIG Q ONE-SHOT HSD POK FB POK EN MAX8554 ______________________________________________________________________________________ Functional Diagrams (continued) OUT Q TRIG ONE-SHOT LATCH ERROR OVP COMP 0.600V 0.720V 0.672V 0.528V ILIM 5µ ...
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... DDR Termination and Point-of-Load Applications R1 20kΩ POK POK FSEL OFF HSD C7 0.22µF 10V MAX8554 REF R4 25.5kΩ ILIM PGND R5 110kΩ GND Figure 1. Typical Application Circuit 1: 12V Input, 2.5V Output 20A with 200kHz Switching Frequency VL R3 20kΩ ...
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... EN/HSD EN/HSD and the output, respectively, and K = 1.7µs. The value of N depends on the configuration of FSEL and is listed in For the MAX8554, the general formula for on-time (t where V HSD and the output, respectively, and K = 1.7µs. The value of N depends on the configuration of FSEL and is ...
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... VTTR with at least a 1µF ceramic capacitor. The voltage at REF is nominally 2.00V. Connect a 0.22µF ceramic bypass capacitor between REF and GND logic input used to enable or shut down the MAX8554. Drive EN high or connect enable the ) + R output. Drive EN low to place the MAX8554 in low- ...
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... Power-Good Output (POK) POK is the open-drain output of the internal window comparators that continuously monitor VTT and VTTR for the MAX8553 and FB for the MAX8554. POK is actively held low in shutdown, and becomes high impedance when the outputs are within 12% of their respective nominal regulation voltage. ...
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... Otherwise, the sense circuitry in the MAX8553/ MAX8554 can interpret the MOSFET gate as “off” while there is actually still charge left on the gate. Use very I short, wide traces measuring 10 squares to 20 squares ...
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Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications peak inductor current at the maximum-defined load current (I ): LOAD(MAX) LIR = + PEAK LOAD MAX ( ) 2 Output-Capacitor ...
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... R FOBK Figure 5. Setting the Foldback Current Limit with Two Resistors, R ILIM and R FOBK The switching frequency of the MAX8553/MAX8554 can be lowered from the value set by FSEL by adding a ILIM resistor voltage-divider to EN/HSD (HSD) as shown in Figure 6. This voltage-divider lowers the voltage the IC ...
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... DRP OUT MAX R should be chosen to handle this power dissipation. DRP Power MOSFET Selection The MAX8553/MAX8554 drive external, logic-level, N- channel MOSFETs as the circuit-switch elements. The key selection parameters are: On-resistance (R ): The lower, the better. DS(ON) Maximum drain-to-source voltage (V should be at least 20% higher than the input supply rail at the high-side MOSFET’ ...
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... Adding series resistors increases the power dissipation of the MOSFET, so ensure that this does not overheat the MOSFET. 22 ______________________________________________________________________________________ × Power dissipation in the MAX8553/MAX8554 IC is pri marily due to the on-chip MOSFETs’ gate drivers (DH and DL). This power dissipation depends on the gate charge of the external MOSFETs used ...
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... PGND BST 13 PGND VTTR TRANSISTOR COUNT: 2827 PROCESS: BiCMOS / π). < f ESR S Pin Configurations HSD POK 3 14 BST MAX8554 PGND ILIM FSEL REF GND 8 9 OUT QSOP Chip Information 23 ...
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Input, Synchronous PWM Buck Controllers for DDR Termination and Point-of-Load Applications (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 ...