el7571c ETC-unknow, el7571c Datasheet
el7571c
Available stocks
Related parts for el7571c
el7571c Summary of contents
Page 1
... EL7571C Programmable PWM Controller General Description The EL7571C 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 ...
Page 2
... EL7571C Programmable PWM Controller Absolute Maximum Ratings Supply Voltage: Input Pin Voltage: -.03 below Ground, +0.3 above Supply VHI Storage Temperature Range: Important Note: All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are at the ...
Page 3
... Programmable PWM Controller Conditions C = 330pF OSC V >1.5V OTEN Oscillator i/p (COSC) driven with HCMOS gate V = 3.5V OUT Function SLOPE synchronizes device to an external clock. SYNC for normal operation. OUT 3 EL7571C Min Typ Max Unit 140 190 240 kHz 50 500 1000 kHz 100 ns 20 800 ns 100/f us ...
Page 4
... EL7571C Programmable PWM Controller Typical Performance Curves +12V Supply Sync Line Regulation 0.004 0.003 0.002 0.001 0 -0.001 -0.002 -0.003 13.5 13.0 12.5 12.0 11.5 11.0 V (V) IN +12V 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 -2.00 ...
Page 5
... I (A) OUT 12V Transient Response 1 +5V Supply +12V Controller Sync w/o Schottky VRM Efficiency 1.0 0.9 0.8 0.7 0.6 0 0.02 1.02 +5V Supply Sync with Schottky VRM Efficiency 1.0 0.9 0.8 0.7 0.6 0 Non-sync Transient Response 1 5 EL7571C Programmable PWM Controller V = 3.5V OUT V = 1.8V OUT V = 2.8V OUT V = 1.3V OUT 3.04 5.04 7.04 9.04 11.04 13.04 I (A) OUT V = 3.5V OUT V = 2.8V OUT V = 1.8V OUT ...
Page 6
... EL7571C Programmable PWM Controller Typical Performance Curves 5V Sync Transient Response 1 Efficiency vs Temperature 92.6 92.5 92.4 92.2 92.0 91.8 91.6 -45 -30 - Temperature (°C) Frequency vs Temperature 280 270 260 250 240 230 220 210 200 -45 -30 - Temperature (°C) 5V Input 12V Controller Transient Response Temperature REF 1.425 1.420 1 ...
Page 7
... Reference A precision, temperature compensated band gap refer- ence forms the basis of the EL7571C. The reference is trimmed during manufacturing and provides 1% set point accuracy for the overall regulator. AC rejection of the reference is optimized using an external bypass capacitor C ...
Page 8
... FET with a Schottky diode, resulting in non-synchronous operation. Applications Information The EL7571C is designed to meet the Intel 5 bit VRM specification. Refer to the VID decode table for the con- troller output voltage range. The EL7571C may be used in a number converter topol- ogies ...
Page 9
... To ensure reliable system operation MIN important to sense the actual voltage drop across the resistor. Accordingly a four wire Kelvin connection should be made to the controller current sense inputs. 9 EL7571C Programmable PWM Controller Transient Complexity Input Noise Response low high good higher ...
Page 10
... Programmable PWM Controller There are two criteria for selecting the resistor value and type. Firstly, the minimum value is limited by the maxi- mum output current. The EL7571C current limit capacitor has a typical threshold of 154mV, 125mV minimum. When the voltage across the sense resistor ...
Page 11
... Finally, the MOSFET must be able to conduct the maxi- mum current and handle the power dissipation. The EL7571C is designed to boot-strap to 12V for 12V d only input converters. In this application, logic level i ...
Page 12
... EL7571C Programmable PWM Controller Manufacturer Model Vgs MegaMos Mi4410 4.5V MegaMos Mip30N03A 4.5V Siliconix Si4410 4.5V Fuji 2SK1388 4V IR IRF3205S 4 Motorola MTB75N05HD 4 Skottky Diode the non-synchronous scheme a flyback diode is required to provide a current path to the output when the high side power MOSFET, Q1, is switched off. The crit- ...
Page 13
... Reference 4V UVLO UVLO LOW + - 3.5V VID (0:4) C SLOPE Ramp Control 240pF C OSC Oscillator 220pF Programmable PWM Controller In Regulation FB C PWRGD Current Reversal + - + - DAC + PWM - Control Logic + - Soft Start ENABLE 13 EL7571C V INP V HI HSD 0.1µF LX 5.1µ OUT LSD 7. 6mF GND GNDP ...
Page 14
... Application Circuits To assist the evaluation of EL7571C, 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. ...
Page 15
... 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)) EL7571C 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 OTEN VH1 20 0.1µ ...
Page 16
... EL7571C Programmable PWM Controller 5V Input Boot-Strapped Synchronous DC:DC Converter ENABLE 240pF C3 C4 220pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571C 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 ...
Page 17
... Input, 12V Controller, Non-Sync Solution ENABLE 220pF C3 C4 220pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571C 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 Programmable PWM Controller 5 1 OTEN ...
Page 18
... EL7571C Programmable PWM Controller 5V Input, 12V Controller, Synchronous DC:DC Converter ENABLE 330pF C3 C4 330pF 1.4V C5 0.1µF POWER GOOD Voltage LD. (VID(0:4)) EL7571C 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 ...
Page 19
... 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 EL7571C 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’ ...
Page 20
... EL7571C Programmable PWM Controller Layout Example To demonstrate the points discussed above, below shows two reference layouts - a synchronous 5V only VRM layout and a synchronous 5V only PC board lay- out. Both layouts can be modified to any application circuit configuration shown on this data sheet. Gerber files of the layouts are available from the factory. ...
Page 21
... Programmable PWM Controller Top Layer Metal Bottom Layer Metal Top Layer Silkscreen 21 EL7571C ...
Page 22
... EL7571C Programmable PWM Controller Top Layer Metal Bottom Layer Metal 22 ...
Page 23
... EL7571C Programmable PWM Controller General Disclaimer Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the cir- cuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement ...