EL7564C Elantec Semiconductor, EL7564C Datasheet
EL7564C
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EL7564C Summary of contents
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... The minimal external components and full functionality make this EL7564C ideal for desktop and portable applications. The EL7564C is specified for operation over the -40°C to +85°C tem- perature range. Typical Application Diagrams C5 0.1µ ...
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... EL7564C Monolithic 4 Amp DC:DC Step-down Regulator Absolute Maximum Ratings Supply Voltage between and GND Voltage LX Input Voltage V Voltage HI 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 ...
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... PGND PGND VIN VIN STP PGND 16 14 STN PGND 15 EL7564CRE (28-Pin HTSSOP) 3 EL7564C Min Typ Max Unit 105 117 130 kHz 25 ns 0.5 V/ 150 OUT 3.3V C10 330µF 2.37k 2.2nF R1 1k ...
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... EL7564C Monolithic 4 Amp DC:DC Step-down Regulator Pin Descriptions Pin Number Pin Name 1 VREF Bandgap reference bypass capacitor; typically 0.1µF to SGND 2 SGND Control circuit negative supply or signal ground 3 COSC Oscillator timing capacitor (see performance curves) 4 VDD Control circuit positive supply; normally connected to VIN through an RC filter ...
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... Load Regulations (V 3.325 V =3.3V O 3.315 3.305 V =1.8V O 3.295 3.285 3.275 0 3 Die Temperature REF 1.27 1.268 1.266 1.264 1.262 1.26 1.258 1.256 5.25 5.5 -50 -10 5 EL7564C (V =3.3V =4. = =5. 1.5 2 2.5 3 3.5 4 Load Current I (A) O =3.3V =5. = =4.5V IN 1.5 2 2.5 3 3.5 4 Load Current I ...
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... EL7564C Monolithic 4 Amp DC:DC Step-down Regulator Typical Performance Curves *Note: The 28-Pin HTSSOP Package Offers Improved Performance Oscillator Frequency vs Temperature 360 350 340 I =4A O 330 320 310 I =0A O 300 290 280 -40 - Temperature (°C) VTJ vs Junction Temperature 1.5 1.3 1.1 0 100 Junction Temperature (°C) ...
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... Power-Down V =5V, V =3.3V Shut-Down V =5V, V =3.3V Monolithic 4 Amp DC:DC Step-down Regulator Power-Up V =5V, V =3.3V Releasing EN V =5V, V =3.3V Short-Circuit Protection V = EL7564C ...
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... EL7564C Monolithic 4 Amp DC:DC Step-down Regulator Block Diagram VTJ Junction Temperature 2.2nF Controller Supply 22 VDD 0.22µF EN STP Power Tracking STN SGND FB 0.1µF 390pF VREF COSC Voltage VDRV Oscillator Reference VHI VIN Power FET PWM Drivers Controller Power FET PGND Current Sense VREF ...
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... Applications Information Circuit Description General The EL7564C is a fixed frequency, current mode con- trolled DC:DC converter with integrated N-channel power MOSFETs and a high precision reference. The device incorporates all the active circuitry required to implement a cost effective, user-programmable 4A syn- chronous step-down regulator suitable for use in DSP core power supplies ...
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... FET, via the VHI pin. A value of 0.22µF for CVHI is recommended. Reference A 1.5% temperature compensated bandgap reference is integrated in the EL7564C. The external VREF capaci- tor acts as the dominant pole of the amplifier and can be increased in size to maximize transient noise rejection. A value of 0.1µF is recommended. Oscillator ...
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... HI output forces the PWM control- ler to skip switching cycle. 1. Linear Tracking In this application always the case that the lower voltage supply V Please see Figure 2 below OUT V P Figure 2. Linear Power Tracking 11 EL7564C tracks the higher output supply TIME . ...
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... EL7564C STP 9 + STN - EL7564C 8 STP 9 + STN - 10 However, due to the superimpose of V choice of R and R A relationship: reaches Where 0.5 is for noise immunity. See Figure 3 below ...
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... EL7564C EL7564C Monolithic 4 Amp DC:DC Step-down Regulator . Figure 4. Offset Tracking 13 EL7564C TIME ...
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... External Soft Start An external soft start can be combined with auxilliary supply tracking to provide desired soft start other than internally preset soft start (Figure 5). The appropriate start-up time is EL7564C STP STN - Figure 5. External Soft Start ...
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... A capacitor can be added to the EN pin to delay the con- verter start-up (Figure 6) by utilizing the pull-up current. The delay time is approximately 1200 EL7564C 8 STP 9 + STN - 10 Monolithic 4 Amp DC:DC Step-down Regulator OUT Figure 6. Start-up Delay 15 EL7564C TIME ...
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... The heat of the chip is mainly dissipated through the PGND pins. Maximizing the copper area around these pins is preferable. In addition, a solid ground plane is always helpful for the EMI performance. The demo board is a good example of layout based on these principles. Please refer to the EL7564C Applica- tion Brief for the layout. 16 ...
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... Package Outline Drawing (20-Pin SO Package) NOTE: The package drawing shown here may not be the latest version. For the latest revision, please refer to the Elantec website at http://www.elantec.com/pages/package_outline.html Monolithic 4 Amp DC:DC Step-down Regulator 17 EL7564C ...
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... EL7564C Monolithic 4 Amp DC:DC Step-down Regulator 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 ...