ADP3168JRUZ-REEL AD [Analog Devices], ADP3168JRUZ-REEL Datasheet
ADP3168JRUZ-REEL
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ADP3168JRUZ-REEL Summary of contents
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FEATURES Selectable 2-, 3-, or 4-phase operation MHz per phase ±10 mV worst-case differential sensing error over temperature Logic-level PWM outputs for interface to external high power drivers Active current balancing between all output phases Built-in ...
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ADP3168 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics and Test Circuits............... 7 Theory of Operation ........................................................................ 9 Number of Phases......................................................................... 9 Master Clock Frequency.............................................................. 9 Output ...
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SPECIFICATIONS All limits at temperature extremes are guaranteed via correlation using standard statistical quality control (SQC). VCC = 12 V, FBRTN = GND 0°C to 85°C, unless otherwise noted. A Table 1. Parameter ERROR AMPLIFIER Output Voltage Range ...
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ADP3168 Parameter CURRENT-LIMIT COMPARATOR ILIMIT Output Voltage Normal Mode Shutdown Mode Output Current, Normal Mode Current-Limit Threshold Voltage Current-Limit Setting Ratio DELAY Normal Mode Voltage DELAY Overcurrent Threshold Latch-Off Delay Time SOFT START Output Current, Soft-Start Mode Soft-Start Delay Time ...
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ABSOLUTE MAXIMUM RATINGS Table 2. Parameter VCC FBRTN VID0 to VID5, EN, DELAY, ILIMIT, CSCOMP, RT, PWM1 to PWM4, COMP SW1-SW4 All Other Inputs and Outputs Operating Ambient Temperature Range Operating Junction Temperature Storage Temperature Range Junction to Air Thermal ...
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ADP3168 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 3. Pin Function Descriptions Pin No. Mnemonic Function VID4 to VID0, VID5 Voltage Identification DAC Inputs. These six pins are pulled internal reference, providing a Logic 1 ...
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TYPICAL PERFORMANCE CHARACTERISTICS AND TEST CIRCUITS 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 SEE EQUATION 1 FOR FREQUENCIES NOT ON THIS GRAPH 100 150 200 R VALUE (kΩ) T Figure 3. Master Clock Frequency vs. RT ...
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ADP3168 Table 4. Output Voltage vs. VID Code (X = Don’t Care) VID4 VID3 VID2 VID1 VID0 ...
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THEORY OF OPERATION The ADP3168 combines a multimode, fixed frequency PWM control with multiphase logic outputs for use in 2-, 3-, and 4-phase synchronous buck CPU core supply power converters. The internal 6-bit VID DAC conforms to Intel’s VRD/VRM 10 ...
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ADP3168 The positive input of the CSA is connected to the CSREF pin, which is connected to the output voltage. The inputs to the amplifier are summed together through resistors from the sensing element (such as the switch node side ...
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Figure 8. Start-Up Waveforms, Circuit of Figure 12. Channel 1—PWRGD, Channel 2—V , Channel 3—High-Side MOSFET V OUT Channel 4—Low-Side MOSFET V CURRENT-LIMIT, SHORT-CIRCUIT, AND LATCH-OFF PROTECTION The ADP3168 compares a programmable current-limit set point to the voltage from the ...
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ADP3168 DYNAMIC VID The ADP3168 incorporates the ability to dynamically change the VID input while the controller is running. This allows the output voltage to change while the supply is running and supplying current to the load. This is commonly ...
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APPLICATION INFORMATION The design parameters for a typical Intel VRD 10 compliant CPU application are as follows: • Input voltage ( • VID setting voltage ( 1.500 V VID • Duty cycle (D) ...
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ADP3168 Another important factor in the inductor design is the DCR, which is used for measuring the phase currents. A large DCR causes excessive power losses, while too small a value leads to L1 470µF/16V × 6 1.6µH NICHICON PW ...
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DESIGNING AN INDUCTOR Once the inductance and DCR are known, the next step is to either design an inductor or find a standard inductor that comes as close as possible to meeting the overall design goals also important ...
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ADP3168 INDUCTOR DCR TEMPERATURE CORRECTION With the inductor’s DCR being used as the sense element and copper wire being the source of the DCR, one needs to com- pensate for temperature changes of the inductor’s winding. Fortunately, copper has a ...
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C SELECTION OUT The required output decoupling for the regulator is typically recommended by Intel for various processors and platforms. One can also use some simple design guidelines to determine what is required. These guidelines are based on having both ...
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ADP3168 POWER MOSFETS For this example, the N-channel power MOSFETs have been selected for one high-side switch and two low-side switches per phase. The main selection parameters for the power MOSFETs are ...
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RAMP RESISTOR SELECTION The ramp resistor ( used for setting the size of the internal R PWM ramp. The value of this resistor is chosen to provide the best combination of thermal balance, stability, and transient response. This ...
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ADP3168 The first step is to compute the time constants for all of the poles and zeros in the system: × × × × DID ...
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C SELECTION AND INPUT CURRENT IN DI/DT REDUCTION In continuous inductor current mode, the source current of the high-side MOSFET is approximately a square wave with a duty ratio equal to n × and an amplitude of one-nth ...
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ADP3168 AC Loadline Setting 11. Remove dc load from circuit and hook up dynamic load. 12. Hook up scope to output voltage and set to dc coupling with time scale at 100 µs/div. 13. Set dynamic load for a transient ...
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LAYOUT AND COMPONENT PLACEMENT The following guidelines are recommended for optimal performance of a switching regulator system. Key layout issues are illustrated in Figure 18. SWITCH NODE 12V CONNECTOR PLANES THERMISTOR KEEP-OUT AREA OUTPUT POWER PLANE KEEP-OUT ...
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... PIN 1 0.15 0.05 COPLANARITY ORDERING GUIDE Model Temperature Range ADP3168JRU-REEL7 0°C to 85°C ADP3168JRU-REEL 0°C to 85°C ADP3168JRUZ-REEL 1 0°C to 85° Pb-free part. © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 9.80 9.70 9. ...