el7571 Intersil Corporation, el7571 Datasheet
el7571
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el7571 Summary of contents
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... Data Sheet Programmable PWM Controller The EL7571 is a flexible, high efficiency, current mode, PWM step down controller. It incorporates five bit DAC adjustable output voltage control which conforms to the Intel Voltage Regulation Module (VRM) Specification for Pentium® II and Pentium® Pro class processors. The controller employs ...
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... RAMP SLOPE I Oscillator Charge Current OSC CHARGE I Oscillator Discharge Current OSC DISCHARGE I VREF Output Current REFMAX 2 EL7571 Operating Temperature Range 0°C to +70°C Operating Junction Temperature 125°C Peak Output Current .3A Power Dissipation .SO20 500mW = 25° 5V 330pF, C ...
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... High side gate drive output. Driver ground referenced to LX. Driver supply may be bootstrapped to enhance low controller input voltage operation. 20 VH1 S Positive supply input for high side FET driver. NOTE: Pin designators Input Output Supply 3 EL7571 = 25° 5V 330pF OSC SLOPE CONDITION = 25° ...
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... Supply Sync Load Regulation 0.04 0. 1.8V OUT V = 2.1V OUT 0. 2.8V OUT 0.01 0 -0.01 -0. (A) OUT +5V Supply Non-Sync Load Regulation 5.00 4. 1.3V OUT 3. 1.8V OUT 2. 2.8V OUT 1.00 0 -1.00 -2. (A) OUT 4 EL7571 0.30 0.20 0.10 0.00 -0.10 -0.20 -0.30 -0.40 11.5 11.0 10.5 10.0 6.00 5.00 4.00 3.00 2.00 1.00 -1.00 -2. 1.0 0.9 0 3.5V OUT 0.7 0.6 0 Supply Line Regulation 5.50 5.25 5.00 4.75 V (V) IN VRM +5V Supply +12V Controller Sync w/o Schottky Load Regulation V = 2.8V ...
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... V = 1.8V OUT -0 1.3V OUT -1.5 -2 (A) OUT +5V Supply Non-Sync VRM Efficiency 1.0 0.9 0 3.5V OUT 0 2.8V OUT V = 1.8V OUT 0 1.3V OUT 0 (A) OUT 12V Transient Response 1 5 EL7571 (Continued) 1.0 0.9 0.8 0.7 0.6 0 1.0 0.9 0.8 0.7 0.6 0 +5V Supply +12V Controller Sync w/o Schottky VRM Efficiency V = 3.5V OUT V = 1.8V OUT V = 2.8V OUT V = 1.3V OUT 0.02 1.02 3.04 5.04 7.04 9.04 11.04 I (A) OUT ...
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... Temperature (°C) Frequency vs Temperature 280 270 260 250 240 230 220 210 200 -45 -30 -15 0 Temperature (° EL7571 (Continued) 1.425 1.420 1.415 1.410 1.405 1.400 1.395 1.390 Input 12V Controller Transient Response Temperature ...
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... Applications Information Circuit Description General The EL7571 is a fixed frequency, current mode, pulse width modulated (PWM) controller with an integrated high precision reference and a 5 bit Digital-to-Analog Converter (DAC). The device incorporates all the active circuitry required to implement a synchronous step down (buck) converter which conforms to the Intel Pentium® ...
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... FET with a Schottky diode, resulting in non-synchronous operation. Applications Information The EL7571 is designed to meet the Intel 5 bit VRM specification. Refer to the VID decode table for the controller output voltage range. The EL7571 may be used in a number converter topologies. ...
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... There are two criteria for selecting the resistor value and type. Firstly, the minimum value is limited by the maximum output current. The EL7571 current limit capacitor has a typical threshold of 154mV, 125mV minimum. When the voltage across the sense resistor ...
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... Finally, the MOSFET must be able to conduct the maximum current and handle the power dissipation. OUT The EL7571 is designed to boot-strap to 12V for 12V only input converters. In this application, logic level MOSFETs are not required. The following table below lists a few popular MOSFETs and their critical specifications. § ...
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... OTEN 4.5V to 3mF 12.6V Reference 4V UVLO UVLO LOW + - 3.5V VID (0:4) C SLOPE 240pF C OSC Oscillator 220pF 11 EL7571 V R (MAX 4.5V 20m: 6.4nF 4.5V 22m: 6.3nF 4.5V 20m: 4.3nF 4V 37m: 4 8m: 17nF (max) 4 7m: 7.1nF The product of forward voltage drop and condition current is a primary source of power dissipation in the convertor. The Schottky diode selected is the International Rectifier 32CTQ030 which has 0 ...
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... Application Circuits To assist the evaluation of EL7571, several VRM applications have been developed. These are described in the converter topologies table earlier in the data sheet. The demo board can be configured to operate with either 12V controller supply, using a 5V FET supply. ...
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... Input, Boot-Strapped Non-Synchronous DC:DC Converter ENABLE 240pF C3 C4 220pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571 5V VRM Bill of Materials - 5V Non Sync Solution COMPONENT MANUFACTURER C1 Sanyo C2 Sanyo C3 C4 C5 IC1 Elantec L1 Pulse Engineering L2 Micrometals R1 DALE Siliconix 13 EL7571 OTEN ...
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... Input Boot-Strapped Synchronous DC:DC Converter ENABLE 240pF C3 C4 220pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571 5V VRM Bill of Materials - 5V Non Sync Solution COMPONENT MANUFACTURER C1 Sanyo C2 Sanyo C3 C4 C5 IC1 Elantec L1 Pulse Engineering L2 Micrometals R1 DALE Q1, Q2 Siliconix 14 EL7571 OTEN ...
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... Input, 12V Controller, Non-Sync Solution ENABLE 220pF C3 C4 220pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571 5V VRM Bill of Materials - 5V Non Sync Solution COMPONENT MANUFACTURER C1 Sanyo C2 Sanyo C7, C8 IC1 Elantec L1 Pulse Engineering L2 Micrometals R1 DALE Siliconix 15 EL7571 5: 1 OTEN VH1 20 R2 ...
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... Input, 12V Controller, Synchronous DC:DC Converter ENABLE 330pF C3 C4 330pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571 5V VRM Bill of Materials - 5V Input, 12V Controller Sync Solution COMPONENT MANUFACTURER C1 Sanyo C2 Sanyo C3 C4 C5, C6 C7, C8 IC1 Elantec L1 Pulse Engineering L2 Micrometals R1 DALE D2 IR Q1, Q2 Siliconix 16 EL7571 C6 0.1µF ...
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... High frequency switching noise may also couple to other control lines. 2. Always place the by-pass capacitors (0.1µF and 1µF) as close to the EL7571 as possible. Long lead lengths will lessen the effectiveness. 3. Separate the power ground (input capacitor ground and ground connections of the Schottky diode and the power MOSFET’ ...
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... EL7571 Top Layer Metal Bottom Layer Metal Top Layer Silkscreen 18 ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 19 EL7571 Top Layer Metal Bottom Layer Metal ...