LM27212SQX/NOPB National Semiconductor, LM27212SQX/NOPB Datasheet
LM27212SQX/NOPB
Specifications of LM27212SQX/NOPB
LM27212SQXTR
Related parts for LM27212SQX/NOPB
LM27212SQX/NOPB Summary of contents
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... IC enters single-phase power-saving operation which significantly enhances the light load efficiency. Typical Application © 2006 National Semiconductor Corporation The LM27212 also has a soft start pin for the external adjustment of soft start speed. The LM27212 combined with the LM27222 series of MOS- FET drivers, provides a layout-friendly, thermally optimized and noise-immune power solution for the mobile platform ...
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Connection Diagrams Top View 48-Lead TSSOP (MTD) Order Number LM27212MTD See NS Package Number MTD48 Ordering Information Order Number LM27212MTD LM27212MTDX LM27212SQ LM27212SQX www.national.com 20152001 Order Number LM27212SQ NS Package Number SQA48A Package Drawing MTD48 MTD48 1000 Units Tape and ...
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Pin Descriptions (TSSOP) Pin 1, VID0: First and least significant bit to program the output voltage, as specified in VID Code table. Pin 2, VID1: 2nd bit to program the output voltage, as specified in VID Code table. Pin 3, ...
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Pin Descriptions (LLP) Pin 1, VID4: 5th bit to program the output voltage, as speci- fied in VID Code table. Pin 2, VID5: 6th and most significant bit to program the output voltage, as specified in VID Code table. Pin ...
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VID Code Table VID ...
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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. VDD XPOK SW1 VRON DE_EN# VOVP, VBOOT VID0 to VID5 STP_CPU#, SLP VSLP, VSTP, SENSE CMP1, CMP2, CMPREF ILIM1, ILIM21, ILIMREF Power Dissipation \TSSOP 25˚ ...
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Electrical Characteristics type apply over a junction temperature range of -5˚C to +110˚C. Unless otherwise specified, VDD = 5V, SGND = DGND = SRCK1 = 0V. (Note 5) (Continued) Symbol Parameter I Dynamic Output Swing Slew SS3 Rate Control Current ...
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... The Absolute Maximum power dissipation should be de-rated by 12.5mW per ˚C above 25˚C ambient. The LM27212 actively limits its junction temperature to about 150˚C. Note 3: For detailed information on soldering plastic small-outline packages, refer to the Packaging Databook available from National Semiconductor Corporation. Note 4: For testing purposes, ESD was applied using the human-body model, a 100pF capacitor discharged through a 1.5kΩ resistor. ...
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Timing Diagram 9 20152004 www.national.com ...
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Block Diagram www.national.com 10 20152003 ...
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Operation Description FIGURE 1. Two-Phase Current-Mode Hysteretic Operation GENERAL The LM27212 is a 2-phase current-mode hysteretic buck regulator controller that meets modern mobile CPU power requirements. The LM27212 operates from a 5V supply and generates two logic signals that can ...
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Operation Description point where X1 (which is now the same as V- because ih is zero) is equal to V+, Channel 2’s top switch gets turned on and ih starts to flow through RH2. In reality, the steady-state voltage across ...
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Operation Description Modes During Normal Operation SLP STP_CPU# DE_EN# Mode Description Vcore = VID - offset Vcore = VID - offset ...
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Design Considerations out ref out In the equations, τ is the delay from error comparator trip point to the instant external power FETs start to switch. For the LM27212 and LM27222, that value is found ...
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Design Considerations calculated on-resistance obtain the on-resistance for each FET. In the case of more FETs, that number is the square of the number of FETs. Since efficiency is very im- portant in most cases, having the ...
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Design Considerations Example: soft start time is preferred to be 1ms to 3ms, initial Vcore is 1.37V, and Dynamic VID / Mode Change slew rate is preferred less than 5mV/µs. So, Double-checking the soft start time: To ...
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Design Considerations SETTING CURRENT LIMIT The current limit comparator compares the voltage pre- established across the current limit set resistor (R13 in Fig- ure 1) and the voltage across the current sense resistors. The current sourced by the ILIMREF pin ...
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Special PCB Layout Considerations www.national.com (Continued) FIGURE 2. PCB Layout Example 18 20152007 ...
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DESIGN 1. (VDC = 8.1V to 21V, IOUT = 32A continuous, Maximum Load Step = 24A) ID Part Number C1 C4532X7R1E106M CAPACITOR, MLC C2 6TPD330M CAPACITOR, POSCAP EEFSD0E221R CAPACITOR VJ0805Y105KXJ CAPACITOR C5 VJ0805Y154KXJ CAPACITOR C6 VJ0805Y154KXJ CAPACITOR C7 ...
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DESIGN 2. (VDC = 8.1V to 21V, IOUT = 25A continuous, Maximum Load Step = 18.6A) ID Part Number C1 C4532X7R1E106M CAPACITOR, MLC C2 6TPD330M CAPACITOR, POSCAP 7.3X4.3X3.8 mm3 EEFSD0E221R CAPACITOR VJ0805Y105KXJ CAPACITOR C5 VJ0805Y154KXJ CAPACITOR C6 VJ0805Y154KXJ ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 48-Lead TSSOP Package Order Number LM27212MTD NS Package Number MTD48 48-Lead LLP Package Order Number LM27212SQ NS Package Number SQA48A 22 ...
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