MAX8524 MAXIM [Maxim Integrated Products], MAX8524 Datasheet
MAX8524
Related parts for MAX8524
MAX8524 Summary of contents
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... Rev 2; 4/ 8-Phase VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage General Description The MAX8525 (VRM 10/VRD 10)/MAX8524 (VRM 9.1/ VRD 9.1) current-mode step-down controllers, the MAX8523 high-speed, dual-phase MOSFET gate driver, and the MAX8552 wide-input, single-phase MOSFET gate driver provide flexible, low-cost, low-voltage CPU core supplies ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage Positioning ABSOLUTE MAXIMUM RATINGS REF, COMP, VID0 to VID5, OSC, CLKI, CLKO to GND ..........................................-0. RS+, RS-, ILIM to GND .................................-0. PWM_ ...
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... Input Low Level V CC Input High Level V CC Input Pulldown Level Internal pulldown Input Pulldown Resistance Internal pulldown MAX8524 LOGIC INPUTS (VID0–VID4) Input Low Level V CC Input High Level V CC Input Pullup Level Input Pullup Resistance Internal pullup resistance MAX8525 LOGIC INPUTS (VID0–VID5) ...
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... CC noted.) PARAMETER Output rising PWRGD Upper Threshold Output falling Output falling PWRGD Lower Threshold Output rising OVP PROTECTION MAX8524 output rising Output Overvoltage Trip Threshold, OVP Action MAX8525 output rising PWM, CKLO OUTPUTS Output Low Level I PWM_ Output High Level I PWM_ ...
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... Internal pullup LOGIC INPUTS (CLKI) Input Low Level V CC Input High Level V CC Input Pulldown Resistance Internal pulldown MAX8524 LOGIC INPUTS (VID0–VID4) Input Low Level V CC Input High Level V CC Input Pullup Resistance Internal pullup resistance MAX8525 LOGIC INPUTS (VID0–VID5) ...
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... From EN rising, tracks CLKO Output rising PWRGD Upper Threshold Output falling Output falling PWRGD Lower Threshold Output rising OVP PROTECTION MAX8524 output rising Output Overvoltage Trip Threshold, OVP Action MAX8525 output rising PWM, CLKO OUTPUTS Output Low Level I PWM_ Output High Level ...
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... DYNAMIC VID RESPONSE, 250mV STEP VOLTAGE MAX8524 toc05 POWER-GOOD OUTPUT PHASE 1 INDUCTOR CURRENT 10A/div OUTPUT VOLTAGE 200mV/div 40µs SOFT-STOP WAVEFORMS AT 1.45V OUTPUT MAX8524 toc07 POWER- GOOD OUTPUT 0A OUTPUT VOLTAGE 0.5V/div OUT 400µs I OUT V OUT 50mV/div POWER- ...
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... TEMPERATURE 2.010 2.005 2.000 1.995 1.990 100 -40 - TEMPERATURE (°C) CLOCK FREQUENCY vs. R OSC 10 100 1000 R RESISTOR (kΩ) OSC CLKO RISE AND FALL TIME vs. TEMPERATURE MAX8524 toc15 RISE FALL -40 ...
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... VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage (V = 12V 1.2V 80A OUT OUT_MAX INTERLEAVED 8-PHASE OPERATION: LX WAVEFORMS MAX8524 toc16 MASTER PH1 MASTER PH2 MASTER PH3 MASTER PH4 SLAVE PH1 SLAVE PH2 SLAVE PH3 SLAVE PH4 1µs PIN ...
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... CLKI GND permits floating this pin. See the Paralleling Operation section for detailed clocking operation. DAC Code Input. The MAX8524 has a 15kΩ internal pullup resistor to V 15–19 16–19 VID0–VID4 requires an external pullup resistor. DAC Code Input. The MAX8525 requires an external pullup resistor. Connect to V — ...
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... In 4-phase operation, the effective switching frequency is 0.6MHz to 4.8MHz. For 8-phase operation, the effective switching frequency is 1.2MHz to 9.6MHz. The MAX8525 includes a 6-bit DAC (Intel VRM 10.0 compliant) and the MAX8524 includes a 5-bit DAC (Intel VRM 9.1 compliant), both able to achieve ±0.4% ______________________________________________________________________________________ VID0 ...
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... OSC pin. 1 1.625 0 1.600 A precision 2V reference is provided by the 1 1.575 MAX8524/MAX8525 at the REF pin. REF is capable of 0 1.550 sourcing up to 500µA for external loads. REF stays alive when EN is low and while V 1 1.525 Connect a 0.22µF ceramic capacitor from REF to GND. ...
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... C is the value of the compensation capacitor. For example, a 1mΩ 2025-package sense resistor has an ESL of 1.6nH. Output Current-Limit and Short-Circuit The MAX8524/MAX8525 provide a cycle-by-cycle cur- rent limit to control the average output current as pro- I OUT grammed by the user at the ILIM pin. This approach is ...
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... Figure 5 shows the clock timing between the phases of both master and slave controllers. 2-Phase and 3-Phase Operation Selection The MAX8524/MAX8525 can operate in 2-, 3-, and 4-phase operation. Connect PWM4 to V 6-phase operation. Also connect PWM2 to V 2-phase operation. All PWM outputs are held low dur- ing shutdown ...
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... Figure 6. Output Overvoltage Protection (OVP) When the output voltage exceeds the regulation volt- age by 225mV for the MAX8524 or 200mV for the MAX8525, all PWM outputs are pulled low and the con- troller is latched off. To discharge the output voltage, the MOSFET drivers must keep the low-side MOSFETs on and high-side MOSFETs off ...
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... When the DC resistance of the output inductor is used for current sensing, the range of DC resistances is limit the following constraints: VID0 VID1 VID2 SLAVE VID3 VID4 VID5 CLKI REF MAX8524/ RS+ MAX8525 COMP RS the switching frequency, I OUT_MAX ( ) × × × − V ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage × ≤ × × OUT MAX _ and N ≥ × × ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage Positioning low-side MOSFETs of each phase can be calculated from the following equation OUT MAX _ = × ...
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... Use the ground plane to shield the current-sense traces and the feedback from noise sources. Place the REF capacitor, the V sense decoupling capacitors, and the remote-sense decoupling capacitors as close to the MAX8524/ MAX8525 as possible. For an example PC board layout, refer to the MAX8525 evaluation kit. TRANSISTOR COUNT: 9021 ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage Positioning Figure 7. Typical Application Circuit for VRM 10 Using a Sense Resistor for Output Current Sensing and 8-Pin SO MOSFET Packages 20 ______________________________________________________________________________________ ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage Figure 8. 600kHz Application Circuit with Direct MOSFETs for Compact VRM 10 Design ______________________________________________________________________________________ Positioning 21 ...
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... R U COMP RS+ RS- GND 22 ______________________________________________________________________________________ SYNC DETECT 1 0.45MHz TO 4.8MHz INTERNAL CLOCK MUX 0 div 2 CURRENT FOLDBACK AND FAULT LOGIC MAX8524 OVP MAX8525 REF SOFT-START 2V ±0.4% 7-BIT DAC COUNTER LOAD GMV 1µs DELAY RAPID- ACTIVE AVERAGE CURRENT SENSE RSDA CLAMP ...
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VRM 10/9.1 PWM Controllers with Precise Current Sharing and Fast Voltage (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.) Maxim cannot assume ...