MAX5950 MAXIM [Maxim Integrated Products], MAX5950 Datasheet
MAX5950
Related parts for MAX5950
MAX5950 Summary of contents
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... Protection features include lossless valley-mode current limit, hiccup-mode output short-circuit protection, and thermal shutdown. The MAX5950 is available in a space-saving 5mm x 5mm, 32-pin thin QFN package and is specified for operation over the -40°C to +85°C extended tempera- ture range. Refer to the MAX5951 data sheet for a pin- compatible, general-purpose PWM controller ...
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PWM Controller with Hot-Swap ABSOLUTE MAXIMUM RATINGS IN to AGND.............................................................-0.3V to +24V HSENSE, PWM_IN to AGND........................-0. GATE to AGND.......................................................-0.3V to +30V GATE to PWM_IN ....................................................-0.3V to +6V PWREN, PWRFLT, MPWRGD, HUVLO, PGI, DCENO to AGND ................................................................-0.3V to ...
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PWM Controller with Hot-Swap ELECTRICAL CHARACTERISTICS (continued 12V PWM_IN IN PWM_IN C = 2.2µ -40°C to +85°C, unless otherwise noted. Typical values are at T REG ...
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PWM Controller with Hot-Swap ELECTRICAL CHARACTERISTICS (continued 12V PWM_IN IN PWM_IN C = 2.2µ -40°C to +85°C, unless otherwise noted. Typical values are at T REG ...
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PWM Controller with Hot-Swap ELECTRICAL CHARACTERISTICS (continued 12V PWM_IN IN PWM_IN C = 2.2µ -40°C to +85°C, unless otherwise noted. Typical values are at T REG ...
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PWM Controller with Hot-Swap (Typical Application Circuits PWM_IN = 2.2µ +25°C, unless otherwise noted.) A HOT-SWAP UNDERVOLTAGE LOCKOUT THRESHOLD vs. TEMPERATURE 1.30 1.27 1.24 1.21 1.18 1.15 -40 - TEMPERATURE ...
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... REG SWITCHING PERIOD vs 100 150 200 250 300 350 400 500 R (kΩ) RT OPEN-LOOP GAIN/PHASE vs. FREQUENCY MAX5950 toc16 100 -10 - 100 1k 10k 100k FREQUENCY (Hz 49.9kΩ 48.7kΩ, C SYNCIN ...
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... TEMPERATURE (°C) STARTUP WAVEFORM MAX5950 toc22b IN 10V/div PWREN 5V/div GATE 1OV/div PWM_IN 1OV/div 1ms/div PWREN SWITCHING FROM HIGH TO LOW STARTUP MAX5950 toc23b V = 12V PWM_IN DCENO = DECENI1 5V/div PGI 5V/div MPWRGD 2V/div PWRFLT 2V/div 40ms/div REG 85 I INRUSH 1A/div V ...
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... PWREN SWITCHING FROM HIGH TO LOW OUT3 SHORTED TO PGND SHORT-CIRCUIT RESPONSE MAX5950 toc26a 2µs/div = 0V 49.9kΩ 48.7kΩ, C SYNCIN RT ILIM TRACKING (FIGURE 1) MAX5950 toc23d DCEN0 - DCENI_ = STARTUP_ 5V/div OUT1 1V/div OUT2 1V/div OUT3 1V/div PGOOD_ 5V/div 400µs/div OVERLOAD RESPONSE ...
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... DL1 5V/div I = 0.5A OUT1 10ns/div EFFICIENCY vs. LOAD CURRENT 100 16V 12V OUT 0 1.0 0 0.5 1.0 1.5 2.0 I (A) LOAD LOAD-TRANSIENT RESPONSE MAX5950 toc33 I OUT1 1A/div V OUT1 20mV/div AC-COUPLED 400µs/div REG LX1 10V/div DL1 5V/div = 1.2V 2.5 ...
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... Synchronization Output. SYNCOUT is a synchronization signal to drive the SYNCIN of a second 15 SYNCOUT MAX5950/MAX5951, if used. Leave SYNCOUT unconnected when not used. Synchronization Input. SYNCIN accepts the SYNCOUT from another MAX5950/MAX5951 and shifts switching by 180°, allowing the reduction of the input bypass capacitors. When used, drive with a 16 SYNCIN frequency at least 20% higher than the frequency programmed through the RT pin ...
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... The device pro- vides short-circuit protection by disconnecting the load 12 ______________________________________________________________________________________ Pin Description (continued) FUNCTION in the event of a fault condition. The MAX5950 features an internal charge pump that provides the gate drive for the external n-channel MOSFET. The MAX5950 PWM controller utilizes a voltage-mode = V = ...
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... Possible faults include a cir- cuit-breaker event, a thermal-shutdown event PGI is not pulled high within 165ms after DCENO goes high. When such a fault is detected, the MAX5950 forces and latches off the inrush-controlled MOSFET, and DCENO goes low to shut down the DC-DC converters. Pulse ...
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... PWM UVLO make time (25ns typ) to prevent shoot-through currents during transition. Oscillator/Synchronization Input (SYNCIN)/ Synchronization Output (SYNCOUT) Use an external resistor program the MAX5950 switching frequency from 100kHz to 1MHz. Choose the appropriate resistor calculate the desired output switching frequency ( ...
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PWM Controller with Hot-Swap TRACKING PGI DCENO DCENI1 THRESH1 PGOOD1 DCENI2 THRESH2 PGOOD2 DCENI3 THRESH3 PGOOD3 STARTUP1 STARTUP2 STARTUP3 Figure 1. Tracking, STARTUP Sequencing, and PGOOD Sequencing Configurations Startup Sequencing (DCENI, THRESH) The DCENI input must be above V ...
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... If three consecutive cycles pass without a current-limit event, the count of N protects against continuous output short circuit. Error Amplifier The MAX5950 features an integrated thermal-overload protection with temperature hysteresis. Thermal-over- (see the load protection limits the total power dissipation in the device and protects it in the event of an extended ther- mal fault condition ...
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... R4 using the following equation: where V Three key inductor parameters must be specified for Procedures operation with the MAX5950: inductance value (L), peak inductor current ( The minimum required inductance is a function of SAT operating frequency, input-to-output voltage differential, and the peak-to-peak inductor current (∆ ...
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... Q threshold. (caused by the The MAX5950 uses a valley current-sense method for current limiting. The voltage drop across the low-side MOSFET due to its on-resistance is used to sense the inductor current. The voltage drop across the low-side MOSFET at the valley point and at I ...
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... At a given temperature, the calculated V be less than the minimum valley current-limit threshold specified. Figure 5 illustrates the effect of the MAX5950 ILIM refer- ence current temperature coefficient to compensate for the variation of the MOSFET R DS(ON) junction temperature range. ...
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PWM Controller with Hot-Swap OUT EA R4 REF GAIN CLOSED-LOOP (dB) GAIN Figure 6. Error Amplifier Compensation Circuit (Closed-Loop and Error-Amplifier Gain ...
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... C The 32-pin TQFN thermally enhanced package can dis- sipate 2.7W. Calculate power dissipation in the MAX5950 as a product of the input voltage and the total REG output current (I cent current (I 6 where Q the low-side and high-side external MOSFETs, f switching frequency of the converter, and I cent current of the device at the switching frequency ...
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... Use the following guidelines to layout the switching voltage regulator: 1) Place the PWM_IN and DREG bypass capacitors close to the MAX5950 PGND pin. Place the REG bypass capacitor close to the AGND pin. 2) Minimize the area and length of the high-current loops from the input capacitor, upper switching MOSFET, inductor, and output capacitor back to the input capacitor negative terminal ...
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... EN SYNCIN RAMP RT OSC SYNCOUT ______________________________________________________________________________________ Simplified Block Diagrams (continued) PWM CONTROLLER DCENI THRESH VREGOK OVL E/A CPWM IMAX REF 0.3V CLK STARTUP SENSE MAX5950 REG 10µA SHDN CURRENT- LIMIT RES IMAX SET OVERLOAD CLK MANAGEMENT R Q REG SET DOMINANT 10µA S PGOOD AGND STARTUP ...
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... PWRFLT MPWRGD MPWRGD THRESH GND PUVLO PGI DCENO PCIe EXPRESSMODULE SLOT THRESH PUVLO 24 ______________________________________________________________________________________ PCIe EXPRESSMODULE (TRACKING GATE HSENSE PWM_IN REG DREG MAX5950 SYNCIN SYNCOUT RT ILIM STARTUP DCENI AGND PGOOD ILIM DREG IN REG MAX5951 SYNCIN SYNCOUT RT ILIM STARTUP DCENI ...
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... MPWRGD THRESH GND PUVLO PGI DCENO PCIe EXPRESSMODULE SLOT THRESH PUVLO ______________________________________________________________________________________ Typical Operating Circuits (continued) PCIe EXPRESSMODULE (STARTUP SEQUENCING DREG GATE HSENSE PWM_IN REG MAX5950 SYNCIN SYNCOUT RT ILIM STARTUP DCENI AGND PGOOD ILIM IN REG DREG MAX5951 SYNCIN SYNCOUT RT ...
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... THRESH GND PUVLO PGI DCENO PCIe EXPRESSMODULE SLOT THRESH PUVLO 26 ______________________________________________________________________________________ Typical Operating Circuits (continued) PCIe EXPRESSMODULE (PGOOD SEQUENCING GATE HSENSE PWM_IN REG DREG MAX5950 SYNCOUT DCENI AGND PGOOD SYNCIN RT ILIM STARTUP ILIM DREG IN REG MAX5951 DCENI SYNCIN SYNCOUT ...
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... PWRFLT MPWRGD MPWRGD GND THRESH PUVLO PGI DCENO PCIe EXPRESSMODULE SLOT ______________________________________________________________________________________ Typical Operating Circuits (continued) USING EXTERNAL CURRENT-SENSE RESISTOR C IN GATE HSENSE PWM_IN REG DREG MAX5950 DCENI AGND PGOOD SYNCIN SYNCOUT RT ILIM STARTUP R RT PROCESS: BiCMOS C BST BST ...
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PWM Controller with Hot-Swap (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 than circuitry ...