Dc to dc synchronous converter design abdus sattar, ixys. A hardware prototype was implemented base on 4phase synchronous buck topology to provide high efficiency and lower cost solution. The tda21472 power stage contains a low quiescentcurrent synchronous buck gate driver ic co packaged with schottky diode, and highside and lowside mosfets. Proceedings of the 2 nd international conference on current trends in engineering and management icctem 2014 17 19, july 2014, mysore, karnataka, india 55 fig 3.
A synchronous buck, sometimes multiphase, is used for this purpose. This driver combined with intersils multiphase buck pwm controllers forms a complete singlestage corevoltage regulator. Control chips that support interleaved channels are. Synchronous rectification type figure 1 shows the circuit diagram of a synchronous rectification type dcdc converter. This is especially helpful in pc and laptop motherboards. This driver, combined with,richteks series of multiphase buck pwm controllers. The output voltage is zero and there is no current through the switch. They are especially suited for mobile computing applications that require high efficiency and excellent thermal performance. Integrated current sensing technology for synchronous buck. Texas instruments, csd95490q5mc synchronous buck nexfet smart. This converter was designed to handle bursts of 500 w peak, which is typical in audio applications. Package the tps51604 device is packaged in a space saving, thermallyenhanced 8pin, 2mm x 2mm wson. Fortunately, some multiphase buck controllers can be easily adapted for use in a 4phase boost converter. Max20751 multiphase master with pmbus interface and.
The ltc3871 is a bidirectional synchronous buck or boost controller to stepdown or stepup the voltage between the 12v and 48v batteries in dual battery automotive applications. The converter has 5 phases and uses discrete noncoupled inductors. Tps40090 data sheet, product information and support. Max8552 highspeed, wideinput, singlephase mosfet driver. Thermal management for multiphase current mode buck converters. Design consideration 1 for synchronous buck converter input voltage, vin 12v output voltage, vo 3. A driverless controller with the fets and ic combined into one ic package. The ltc3861 is a dual polyphase synchronous step down switching regulator controller for high current distributed. At the same time, the synchronous mosfet plays an important role in determining the performance of the synchronous buck converter. Agenda texas instruments 201415 power supply design seminar 42.
Under the hood of a multiphase synchronous rectified boost. Emc guideline for synchronous buck converter design. The isl6614 integrates two isl66 mosfet drivers and is specifically designed to drive two independent power channels in a multiphase interleaved buck converter topology. Improvement of the dynamic performance of a multiphase. For buck converter, the ideal duty cycle is the ratio of the output voltage and input voltage. Multiphase buck design from start to finish, part 1 texas instruments. Thermal management for multiphase current mode buck. One suitable approach is to use a multiphase buck controller. A multiphase synchronous buck converter having plural single phase synchronous buck converter stages, connected together to provide an output current to a load. The max8523 is available in a spacesaving 16pin qsop package and. The isl6612 and isl66 are high frequency mosfet drivers specifically designed to drive upper and lower power nchannel mosfets in a synchronous rectified buck converter topology. Up to six smart slave ics, plus a master ic, provide a compact synchronous buck converter. Highspeed, dualphase gate driver for multiphase, stepdown converters. These drivers combined with hip63xx or isl65xx multiphase buck pwm controllers and nchannel mosfets form complete corevoltage regulator solutions for advanced.
The control ics of both the multiphase buck converter and the scpc can be highly integrated, so any cost differential is small. Controller for multiphase interleaved buck converter. The switching signals for each of the power trains are out of phase. High performance low voltage power mosfet for high. A pointofload converter, or pol, is a nonisolated buck converter thats capable of efficiently driving power to high current loads. A multiphase converter consists of paralleled power trains which drive a common load.
These drivers combined with hip63xx or isl65xx multiphase buck pwm controllers and nchannel mosfets form complete corevoltage regulator solutions for advanced microprocessors. The tps40180 is a single synchronous buck controller that can be stacked for a multiphase output. The tps40090evma 001 multiphase dctodc converter utilizes the tps40090 multiphase controller and ucc27222 predictive gate driver to step down a 12v input to 1. The results of load line meets the intel specification in different modes of operation, provides the best transient responses, and meets the specification during the load transient. The isl6614a integrates two isl66a mosfet drivers and is specifically designed to drive two channel mosfets in a synchronous rectified buck converter topology. Mosfet driver with dual outputs for synchronous buck converters the ncp3420 is a single phase 12 v mosfet gate driver optimized to drive the gates of both high. Analysis and design optimization of multiphase converter. It is a class of switchedmode power supply smps typically containing at least two semiconductors a diode and a transistor, although modern buck converters frequently replace the diode with a second transistor used for. Figure 2 shows the waveforms of the voltage of a switch node and the current waveform of the inductor. An example of a multiphase synchronous buck converter that can be used to power a microprocessor load is illustrated in fig. There are many industrystandard multiphase buck controllers and converters available today. Hi everyone i have to build an interleaved buck converter. Max8523 highspeed, dualphase gate driver for multiphase, step.
Fan5093 two phase interleaved synchronous buck converter. Good understanding of power losses in a synchronous buck converter is critical for improving converter performance. The isl6208 and isl6208b are high frequency, dual mosfet drivers, optimized to drive two nchannel power mosfets in a synchronous rectified buck converter topology. In addition, the oicc is implemented as a synchronous buck converter with pcmc, thus reducing its influence on the system efficiency. Switched current power converter edward herbert march, 2006 page 14 of 19 control. The hip2105 and hip2106a are high frequency mosfet drivers optimized to drive two nchannel power mosfets in a synchronous buck converter topology. The device is constructed of a plurality of single phase buck converter stages, and a sensing circuit for each converter stage to generate an output signal representative of the output current provided by that converter stage. High voltage synchronous rectified buck mosfet driver. Beijing university of aeronautics and astronautics, 2005 m.
When the highside switch turns on, the voltage across the draintosource of the lowside synchronous mosfet rapidly increases, producing a fastchange in voltage, dv, within a very. The hip2105 has hili inputs and the hip2106a has a single pwm input. Toronto 2011 abstract the main goal of this thesis is to develop an active thermal management control scheme for multiphase current mode buck converters in order to improve the long term reliability of the. The vt1697sb is a featurerich smart slave ic designed to work with maxims seventhgeneration masters to implement a highdensity multiphase voltage regulator. The max8552 highly integrated monolithic mosfet driver can drive a pair of. Tps51604 synchronous buck fet driver for highfrequency cpu core power 1 features 3 description the tps51604 drivers are optimized for high1 reduced deadtime drive circuit for optimized. Multiphase synchronous buck topology in the multiphase buck converter topology, one important operating parameter is called the duty cycle d. This article uses the max8686 controller to compare the performance of a coupledchoke vs. The ncp5351 is an excellent companion to multiphase controllers that do not have integrated gate drivers, such as on semiconductors cs5323, cs5305 or. The implementation of the twoinductor, fourswitch pwm. The controller can be used to make single output systems up to 8 phases. Vt1697sb smart slave ic with integrated current and.
Lowpower loss and highly efficient synchronous buck converters are in great demand for advanced microprocessors of the future. Benefits of a multiphase buck converter introduction singlephase buck controllers work well for lowvoltage converter applications with currents of up to approximately 25 a, but power dissipation and efficiency start to become an issue at higher currents. This driver combined with an intersil isl63xx or isl65xx multiphase pwm controller forms a complete singlestage corevoltage. The ir3537chl8510 is a high efficiency gate driver which. Analysis and design optimization of multiphase converter by kejiu zhang b. An968 ds00968apage 2 2005 microchip technology inc. Ncp81158 synchronous buck mosfet driver the ncp81158 is a high. Synchronous rectified boost converter reproduced from 2014 texas instruments power supply design seminar sem2100. Digital control compatible synchronous buck gate drivers with current sense. Multiphase synchronnous buck stepdown converter multiphase synchronous rectified stepdown or so called buck converter is most commonly used in pc motherboards. Multiphase synchronous buck converter with improved power.
The package is optimized for pcb layout, heat transfer, driver mosfet control timing, and minimal switch node ringing when layout guidelines are followed. Both these drivers, combined with renesas multiphase buck pwm controllers, form a complete singlestage corevoltage regulator. Voltage mode dcdc controller with accurate current sharing. Block diagram of single stage buck converter the simulation is designed for synchronous buck converter for the stage n1, where n is the. The driver, combined with an intersil multiphase buck pwm controller, forms a complete singlestage corevoltage regulator solution for advanced mobile microprocessors. Evan reutzel, rengang chen, scott ragona, and david jauregui 20 integrated current sensing technology for synchronous buck converters. Programmable multiphase synchronous buck converter with pmbus the ncp4201 is an integrated power control ic with a pmbus interface. Multiphase boost converter powers car audio amp power. Therefore, a multiphase buck converter package is desired which would easily permit a user to add such a converter to an existing circuit. The synchronous buck converter is a widely used topology in lowvoltage, highcurrent applications. Two phase interleaved synchronous buck converter for vrm 9.
The advantages of designing buck converters digikey. Mcp1612 buck controller an ideal solution for a spacecontained design. Utilizing maxims smartslave ics, the device provides a highdensity and flexible solution that can be tailored to a range of power loads used in communication equipment. Multiphase synchronous buck converter with improved power loss balancing. Multiphase interleaving buck converter with inputoutput. Dc to dc synchronous converter design abdus sattar, ixys corporation ixan0068 7 design example 1. In addition to steadystate operation, modern multiphase controllers are required to drive the buck converter in other operating modes including. It is used to reduce the supply voltage of the atx usually 12v, 5v sometimes to a lower voltage usually only about 1.
The reverse recovery of its body diode and the cdvdt. Unfortunately, prior art multiphase buck converters are not modular units. It will work in many applications with 5, 12 and 24 v inputs. Multiphase synchronous buck converter using ucd9112 and two ucd7230. Improve twophase buck converter performance with a. University of central florida, 2008 a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy in the department of electrical engineering and computer science. Switched mode dcdc converters, including switching regulators, switching controllers, and pmics that have multiple outputs, provide additional benefits if they offer multiphase functionality. Ringing in the switching waveform of the switching power supply e. Modern microprocessors run off very low voltage, typically 1. Ncp5355 datasheet 12v synchronous buck power mosfet. Ncp5355 12v synchronous buck power mosfet driver the ncp5355 is a dual mosfet gate driver optimized to drive the gates of both high. Mosfets in a synchronousrectified buck converter topology.
The is an excellent companion to multiphase controllers that. Buck converters and their cool applications technical. Taufik practical design of buck converter associate. The response time is limited by the didt of the inductors. Design, analysis and implementation of multiphase synchronous buck dcdc converter for transportable processor huy nguyen abstract as laptop mobile users expect more application features and long battery life, the processor current has to increase to response the demanding while the voltage has to decease to save the power loss. Isl6609, isl6609a synchronous rectified mosfet driver datasheet the isl6609, isl6609a is a high frequency, mosfet driver optimized to drive two nchannel power mosfets in a synchronousrectified buck converter topology. The mcp1612 is packaged in both an 8pin msop and a thermallyenhanced, 8pin dfn.
A multiphase buck regulator is a parallel set of buck power stages as shown in figure 1. Dvdt immunity improved in synchronous buck converters. The ltc3811 is a dual, polyphase synchronous step down switching regulator controller optimized for output. Switching regulator ic efficiency of buck converter. Digital control compatible synchronous buck 4a drivers with.
It is especially suited for mobile computing applications that require high efficiency and excellent thermal performance. Although common practice is to apply interleaving in low voltage high current vrm applications, i am expected to build a converter with output 3040v 2030 a, i. Multiphase synchronous rectified boost converter david baba. A scalable multiphase buck converter with average current. Analysis and design of multiphase multiinterleave dcdc. Multiphase buck converters with extended duty cycle. A buck converter stepdown converter is a dctodc power converter which steps down voltage while stepping up current from its input supply to its output load. Csd95372aq5m slps416c june 2014revised march 2015 csd95372aq5m synchronous buck nexfet power stage 1 features 2 applications 1 60 a continuous operating current capability multiphase synchronous buck converter 92. Using the dualphase synchronous buck controller lm3754, ti has created a highpowerdensity evaluation board that delivers 1. Multiphase synchronous buck converter with improved output.