EL7551C Elantec Semiconductor, EL7551C Datasheet
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EL7551C
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EL7551C Summary of contents
Page 1
... With proper external components, the whole converter fits 2 into a less than 0.4 in area. The minimal external components and small size make this EL7551C ideal for desktop and portable applications. The EL7551C is specified for operation over the -40°C to +85°C tem- perature range. Typical Application Diagram 1 SGND PGND ...
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... EL7551C - Preliminary Monolithic 1 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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... Voltage feedback input. Connected to an external resistor divider between VOUT and GND. A 125nA pull-up current forces VOUT the event that FB is floating. 15 VREF Bandgap reference bypass capacitor. Typically 0.1µF to GND. 16 PGND Ground return of the regulator. EL7551C - Preliminary Monolithic 1 Amp DC:DC Step-down Regulator Pin Function 3 ...
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... EL7551C - Preliminary Monolithic 1 Amp DC:DC Step-down Regulator Typical Performance Curves Efficiency =5V IN 100 V =2.5V V =1. =1. =3. =500kHz 65 S L=Coilcraft DO3316P-472 60 0.1 0.2 0.4 0.6 Load Current I (A) O Efficiency =3.3V O 100 V =4. = =5. =500kHz 65 S L=Coilcraft DO3316P-472 ...
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... OSC 1400 1200 1000 800 600 400 200 0 0 200 400 600 C (pF) OSC Transient Response V =5V, V =3.8V, I =0A- EL7551C - Preliminary Monolithic 1 Amp DC:DC Step-down Regulator Input Current vs Temperature (Enable connected to GND) 0.96 0.94 0.92 0.9 0.88 0.86 0.84 0.82 0.8 80 120 -40 Switching Waveforms V =5V, V =3.8V ...
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... EL7551C - Preliminary Monolithic 1 Amp DC:DC Step-down Regulator Typical Performance Curves Power-Down V =5V, V =3.8V Shut-Down V =5V, V =3.8V Releasing EN V =5V, V =3.8V Short-Circuit Protection V = ...
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... Block Diagram VREF Voltage Reference Controller Supply 39 VDD 0.1µF EN SGND FB EL7551C - Preliminary Monolithic 1 Amp DC:DC Step-down Regulator 0.1µF 270pF COSC Thermal VDRV Oscillator Shut-down VHI VIN Power FET PWM Drivers Controller Power FET PGND Current Sense 7 0.1µF 10µH V OUT 2370 47µF 1k ...
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... Monolithic 1 Amp DC:DC Step-down Regulator Applications Information Circuit Description General The EL7551C 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 1A syn- chronous step-down regulator suitable for use in DSP core power supplies ...
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... VHI pin. A value of 0.1µF for CVHI is recommended. Reference A 1.5% temperature compensated bandgap reference is integrated in the EL7551C. 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. EL7551C - Preliminary ...
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... 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 EL7551C Applica- tion Brief for the layout ...
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... EL7551C - Preliminary Monolithic 1 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 ...