LP2994M National Semiconductor, LP2994M Datasheet
LP2994M
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LP2994M Summary of contents
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... The LP2994 also in- corporates an active low shutdown pin to tri-state the output during Suspend To Ram (STR) states. Patents Pending Typical Application Circuit © 2002 National Semiconductor Corporation Features n Source and sink current n Low external component count n Independent analog and power rails ...
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... Connection Diagram Pin Description SO-8 Pin Ordering Information Order Number Package Type LP2994M LP2994MX www.national.com SO-8 (M08A) Package 20045902 Top View Name NC No internal connection GND Ground VSENSE Feedback pin for regulating VTT SD Active low shutdown pin VDDQ Input for internal reference equal to VDDQ/2 ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. PVIN, AVIN, VTT, VDDQ GND Storage Temp. Range Junction Temperature Lead Temperature (Soldering, 10 sec) ESD Rating (Note 2) Electrical Characteristics type apply over the full Operating Temperature Range (T AVIN = PVIN = 2 ...
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Typical Performance Characteristics (25˚ Temperature ( (0, 25, and 125˚ www.national.com 20045914 = 2.5V) IN 20045916 20045918 (0, 25, and 125˚C) IN 20045915 I ...
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Typical Performance Characteristics V and (25˚ Maximum Sourcing Current 2.5V 2.5V) DDQ IN Maximum Sinking Current 2.5V) DDQ (Continued) Maximum Sourcing Current vs AV ...
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Typical Performance Characteristics Maximum Sinking Current 1.8V) DDQ (0, 25, 85, and 125˚C) TT OUT www.national.com (Continued) Maximum Sourcing Current DDQ 20045926 20045929 1.8V ...
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Block Diagram Description The LP2994 is a linear bus termination regulator designed to meet the JEDEC requirements of SSTL-2 and SSTL-3. The output capable of sinking and sourcing current while TT regulating the output voltage equal to V ...
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Pin Descriptions AVIN and PVIN AVIN and PVIN are the input supply pins for the LP2994. AVIN is used to supply all the internal control circuitry. PVIN, however, is used exclusively to provide the rail voltage for the output stage ...
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Component Selection dielectric types have poor capacitance characteristics as a function of voltage and temperature. Because of the typically low value of capacitance it is recommended to use ceramic capacitors in parallel with another capacitor such as an aluminum electrolytic. ...
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Typical Application Circuits Several different application circuits have been shown in Figure 4 through Figure 13 to illustrate some of the options that are possible in configuring the LP2994. Graphs of the individual circuit performance can be found in the ...
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Typical Application Circuits FIGURE 6. SSTL-2 Implementation with higher voltage rails DDR-II Applications With the separate V pin and an internal resistor divider it DDQ is possible to use the LP2994 in applications utilizing DDR-II memory. Figure 7 and Figure ...
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Typical Application Circuits (Continued) how to use two resistors to level shift V reference voltage of V /2. To calculate the exact voltage DDQ at V the following equation can be used. TT Conversely, the R2 resistor can be placed ...
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Typical Application Circuits FIGURE 11. Creating a Reference Voltage for Memory and Chipsets Output Capacitor Selection For applications utilizing the LP2994 to terminate SSTL-2 I/O signals the typical application circuit shown in Figure 12 can be implemented. FIGURE 12. Typical ...
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Typical Application Circuits (Continued) with the DDR-SDRAM DIMMs mounted on modules result bulk aluminum electrolytic capacitors in the range of 1000uF are typically used. PCB Layout Considerations 1. The input capacitor for the power rail should be placed ...
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... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...