MAX5037 MAXIM [Maxim Integrated Products], MAX5037 Datasheet
MAX5037
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MAX5037 Summary of contents
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... PC board-embedded planar magnetics achieving superior reliability, current sharing, thermal management, compact size, and low system cost. The MAX5037 also features a clock input (CLKIN) for syn- chronization to an external clock, and a clock output (CLKOUT) with programmable phase delay (relative to CLKIN) for paralleling multiple phases ...
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VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller ABSOLUTE MAXIMUM RATINGS IN to SGND.............................................................-0.3V to +30V BST_ to SGND…………………………………….… .-0.3V to +35V DH_ to LX_ .................................-0.3V to [(V DL_ to PGND ..............................................-0. BST_ to LX_ ..............................................................-0.3V to +6V V ...
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VRM 9.0, Dual-Phase, Parallelable, ELECTRICAL CHARACTERISTICS (continued +5V, circuit of Figure (Note 1) PARAMETER SYMBOL Non-Overlap Time OSCILLATOR AND PLL Switching Frequency PLL Lock Range PLL Locking Time CLKOUT Phase Shift (at ...
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VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller ELECTRICAL CHARACTERISTICS (continued +5V, circuit of Figure (Note 1) PARAMETER SYMBOL SENSE+ to SENSE- Input R Resistance VOLTAGE-ERROR AMPLIFIER (EAOUT) Open-Loop Gain A VOL(EA) ...
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VRM 9.0, Dual-Phase, Parallelable, (Circuit of Figure +25°C, unless otherwise noted.) A EFFICIENCY vs. OUTPUT CURRENT AND INTERNAL OSCILLATOR FREQUENCY 100 500kHz 250kHz + ...
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... CNTR 1.75 1. 200kΩ CNTR R = ∞ CNTR 1. +12V IN VID SETTING = +1.75V 1. (A) LOAD DIFFERENTIAL AMPLIFIER BANDWIDTH MAX5037 toc17 90 3.5 45 3.0 PHASE 0 2.5 -45 2.0 -90 1.5 -135 GAIN 1.0 -180 0.5 -225 0 -270 0.01 0 FREQUENCY (MHz) OVERVOLTAGE THRESHOLD (OVPOUT) vs. INPUT VOLTAGE 2.1 2 +1.8V OUT 1 ...
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... SINK AND SOURCE CURRENT DH_ V = +12V V = +12V 22nF f = 250kHz DH_ SW 100ns/div PLL LOCKING TIME 250kHz TO 500kHz AND 500kHz TO 250kHz MAX5037 toc26 CLKOUT 5V/div 500kHz PLLCMP 200mV/div 250kHz 0 100µs/div 12.0 13.0 MAX5037 toc24 DH_ 1.6A/div MAX5037 toc27 V = +12V IN NO LOAD 7 ...
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... MAX5037 toc35 V PGOOD 1V/div V OUT 1V/div V IN 5V/div V = +12V +1.75V OUT I = 52A OUT 1ms/div HIGH-SIDE DRIVER (DH_) FALL TIME MAX5037 toc30 DH_ 2V/div V = +12V 22nF DH_ 40ns/div OUTPUT RIPPLE MAX5037 toc33 DL_ 2V/div V = +12V +1.75V OUT I = 52A OUT ...
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VRM 9.0, Dual-Phase, Parallelable, PIN NAME DAC Code Inputs. VID0 is the LSB and VID4 is the MSB for the internal 5-bit DAC (Table 1). Connect to VID3–VID0, 1–4, 44 SGND for logic low or leave open circuit for logic ...
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... Oscillator Output. CLKOUT is phase shifted from CLKIN by the amount specified by PHASE. Use 36 CLKOUT CLKOUT to parallel additional MAX5037s. CMOS Logic Clock Input. Drive the internal oscillator with a frequency range between 125kHz and 600kHz. The PWM frequency defaults to the internal oscillator if CLKIN is connected to V ...
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... VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller EN +5V IN LDO REGULATOR INTERNAL CIRCUITS V DD CSP1 CSN1 CLP1 SGND MAX5037 PHASE- CLKIN LOCKED LOOP CLKOUT PLLCMP RAMP GENERATOR DIFF SENSE- +0.6V DIFF AMP SENSE+ CNTR ADAPTIVE VOLTAGE REG POSITIONING EAOUT EAN ERROR AMP VID0 ...
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... VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller Detailed Description The MAX5037 (Figures 1 and 2) average current-mode PWM controller drives two out-of-phase buck converter channels. Average current-mode control improves cur- rent sharing between the channels while minimizing component derating and size. Parallel multiple ...
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... VRM 9.0, Dual-Phase, Parallelable, Dual-phase converters with an out-of-phase locking arrangement reduce the input and output capacitor rip- ple current, effectively multiplying the switching fre- quency by the number of phases. Each phase of the MAX5037 consists of an inner average current loop V = +8V TO +28V ...
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... UVLO eliminates “chattering” during startup. Most of the internal circuitry, including the oscillator, turns on when the input voltage reaches +4V. The MAX5037 draws up to 4mA of current before the input voltage reaches the UVLO threshold. The power-on reset clears the overvoltage protection (OVP) fault latch at the UVLO threshold to avoid unintentional OVP latching ...
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... R8 R7, FIGURES 1 AND Figure 3. MAX5037 Control Loop ______________________________________________________________________________________ Average Current-Mode Controller The outer voltage control loop consists of the differen- tial amplifier (DIFF AMP), adaptive voltage-positioning (AVP) block, digital-to-analog converter (DAC), and voltage-error amplifier (VEA). The unity-gain differential amplifier provides true differential remote sensing of the output voltage ...
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... The difference between SENSE+ and SENSE- regulates to the pro- grammed VID output voltage. Connect SENSE external resistor-divider network at the output voltage to use the MAX5037 for output voltages higher than those allowed by the VID codes. PEAK CURRENT COMPARATOR ...
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VRM 9.0, Dual-Phase, Parallelable, Voltage-Error Amplifier The VEA sets the gain of the voltage control loop. The VEA determines the error between the differential amplifier output and the reference voltage generated from the DAC. The VEA output clamps to 0.9V ...
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... The DAC programs the output voltage. The DAC typi- cally receives a digital code, alternatively, the VID inputs are hard-wired to SGND or left open-circuit. VID0–VID4 logic can be changed while the MAX5037 is active, initiating a transition to a new output voltage level. Change VID0–VID4 together, avoiding greater than 1µ ...
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... P SCR. When the crowbar SCR turns on, a fuse must blow or the source current for the MAX5037 regulator must be limited to prevent further damage to the exter- nal circuitry. Connect the SCR close to the input source and after the fuse. Use an SCR large enough to handle ...
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... Parallel Operation For applications requiring large output current, parallel up to three MAX5037s (six phases) to triple the available output current. The paralleled converters operating at the same switching frequency but different phases keep the capacitor ripple RMS currents to a minimum. Three par- allel MAX5037 converters deliver up to 180A of output current ...
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... VRM 9.0, Dual-Phase, Parallelable, Applications Information Each MAX5037 circuit drives two 180° out-of-phase channels. Parallel two or three MAX5037 circuits to achieve four- or six-phase operation, respectively. Figure 1 shows the typical application circuit for two- phase operation. The design criteria for a two-phase converter includes frequency selection, inductor value, input/output capacitance, switching MOSFETs, sense resistors, and the compensation network ...
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... VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller SENSE+ SENSE PHASE V CC CLKIN DIFF EAN EAOUT Figure 10. Parallel Configuration of Multiple MAX5037s 22 ______________________________________________________________________________________ CSN1 CSP1 V IN DH1 LX1 DL1 MAX5037 V IN DH2 LX2 DL2 CSP2 CSN2 PGND SGND CLKOUT CSN1 CSP1 CLKIN ...
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... EN PLLCMP IN CLKIN SENSE- SENSE+ CSN1 CSP1 23 DH1 Q5 24 LX1 25 DL1 Q6 22 BST1 R16 C62 MAX5037 1µF (SLAVE DH2 Q7 31 LX2 30 DL2 Q8 34 BST2 CLP1 CLP2 PGND SGND PHASE PGOOD CSN2 CSP2 20 ...
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VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller Table 3. Component Suppliers SUPPLIER Murata ON Semiconductor Panasonic TDK Vishay-Siliconix 1-800-551-6933 Number of Phases Selecting the number of phases for a voltage regulator depends mainly on the ratio of input-to-output voltage (operating ...
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... L from DH1, DH2, DL1, and DL2. The power dissipated in the MAX5037 is proportional to the input voltage and the average drive current. See the V section to determine the maximum total gate charge allowed from all the driver outputs together. ...
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VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller For example, from the typical VRM specifications in the Applications Information section with V the high-side and low-side MOSFET RMS currents are 9.9A and 24.1A, respectively. Ensure that the thermal impedance of the ...
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... PC board. Also, select a non-inductive resistor with the appropriate wattage rating. The main control loop consists of an inner current loop and an outer voltage loop. The MAX5037 uses an aver- age current-mode control scheme to regulate the out- put voltage (Figure 3). I ...
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... Sense the current right at the pads of cur- rent-sense resistors. 7) Avoid long traces between the V tors, driver output of the MAX5037, MOSFET gates and PGND pin. Minimize the loop formed by the V bypass capacitors, bootstrap diode, bootstrap DD capacitor, MAX5037, and upper MOSFET gate ...
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VRM 9.0, Dual-Phase, Parallelable, (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.) ______________________________________________________________________________________ Average Current-Mode Controller Package Information 29 ...
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VRM 9.0, Dual-Phase, Parallelable, Average Current-Mode Controller (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 responsibility for use of any circuitry other ...