PWM is inherently digital. The switching device cannot control the amplitude of the output directly, so ferrites / inductors / chokes are used with capacitors to lower the deviation of the output signal and limit the rate of change. You can factor their effect into the design pretty easily using Laplace transforms and considering the effect of switching frequency (put everything in the s-domain and it all falls through pretty easily). PWM stands for Pulse Width Modulation - increase the on-to-off ratio (also known as duty cycle) and the output will veer towards a value set by the supply voltage and switching losses in the circuit, which in turn are frequency dependent. Therefore, by controlling the duty cycle you control the nominal amplitude of the output voltage. So PWM is inherently digital - as it cannot be done without a digital component to the control loop - and I repeat: what does Digital PWM mean?
In the grand scheme of worldwide electronics manufacture, I'm afraid Asus are a drop in the ocean compared to the likes of BCM in Malaysia or Nokia. Even if it were on these scales, ferrites are the most economic way to add induction to the output of an SMPSU. Also look at the price against rated switch voltage and quiescent current for an IC and you will see again: more expensive. Then look at Rds(on) characteristics of MOSFETs against price. Guess what? You can research this at FEC or RS. I'm sorry, more phases = cheaper.
Will you be reviewing EVGA's 132-BL-E758-A1? Its selling for the same price as the P6T Deluxe on Newegg, and it comes with 3-way SLI. I'm definitely thinking about one of those as I love EVGA products.
PWM is inherently digital. The switching device cannot control the amplitude of the output directly, so ferrites / inductors / chokes are used with capacitors to lower the deviation of the output signal and limit the rate of change. You can factor their effect into the design pretty easily using Laplace transforms and considering the effect of switching frequency (put everything in the s-domain and it all falls through pretty easily). PWM stands for Pulse Width Modulation - increase the on-to-off ratio (also known as duty cycle) and the output will veer towards a value set by the supply voltage and switching losses in the circuit, which in turn are frequency dependent. Therefore, by controlling the duty cycle you control the nominal amplitude of the output voltage. So PWM is inherently digital - as it cannot be done without a digital component to the control loop - and I repeat: what does Digital PWM mean?
In the grand scheme of worldwide electronics manufacture, I'm afraid Asus are a drop in the ocean compared to the likes of BCM in Malaysia or Nokia. Even if it were on these scales, ferrites are the most economic way to add induction to the output of an SMPSU. Also look at the price against rated switch voltage and quiescent current for an IC and you will see again: more expensive. Then look at Rds(on) characteristics of MOSFETs against price. Guess what? You can research this at FEC or RS. I'm sorry, more phases = cheaper.
The PWM is what runs the DC-DC converter, it should be a buck converter in this case. The very basic principle of the system is to 'squirt' a bit of power into some output caps as needed to keep the voltage at a constant level. IIRC, the inductors provide the current, but I was never all that good at the theory :)
One problem with all this is that there is still high frequency noise, that of the base frequency that gets modulated. More phases is to try and do a sort of noise canceling and provide cleaner power as I understand it. More phases means less power between the phases, and that should mean less stress to the components because there is a LOT of current at those voltages and wattages.
I belive the differences between analog and digital are in what is controlling the duty cycle. In an analog system, an analog timer generate the duty cycle. In a digital system, it would be a microcontroller or logic circuit.
I don't know which set up is better. With analog, I would think component value drift would be a problem. With digital, I would guess it would be the granularity based on the microcontroller's clock, or sample rate of the ADC it would probably need.
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PWM is inherently digital. The switching device cannot control the amplitude of the output directly, so ferrites / inductors / chokes are used with capacitors to lower the deviation of the output signal and limit the rate of change. You can factor their effect into the design pretty easily using Laplace transforms and considering the effect of switching frequency (put everything in the s-domain and it all falls through pretty easily). PWM stands for Pulse Width Modulation - increase the on-to-off ratio (also known as duty cycle) and the output will veer towards a value set by the supply voltage and switching losses in the circuit, which in turn are frequency dependent. Therefore, by controlling the duty cycle you control the nominal amplitude of the output voltage. So PWM is inherently digital - as it cannot be done without a digital component to the control loop - and I repeat: what does Digital PWM mean?
In the grand scheme of worldwide electronics manufacture, I'm afraid Asus are a drop in the ocean compared to the likes of BCM in Malaysia or Nokia. Even if it were on these scales, ferrites are the most economic way to add induction to the output of an SMPSU. Also look at the price against rated switch voltage and quiescent current for an IC and you will see again: more expensive. Then look at Rds(on) characteristics of MOSFETs against price. Guess what? You can research this at FEC or RS. I'm sorry, more phases = cheaper.
The PWM is what runs the DC-DC converter, it should be a buck converter in this case. The very basic principle of the system is to 'squirt' a bit of power into some output caps as needed to keep the voltage at a constant level. IIRC, the inductors provide the current, but I was never all that good at the theory :)
One problem with all this is that there is still high frequency noise, that of the base frequency that gets modulated. More phases is to try and do a sort of noise canceling and provide cleaner power as I understand it. More phases means less power between the phases, and that should mean less stress to the components because there is a LOT of current at those voltages and wattages.
I belive the differences between analog and digital are in what is controlling the duty cycle. In an analog system, an analog timer generate the duty cycle. In a digital system, it would be a microcontroller or logic circuit.
I don't know which set up is better. With analog, I would think component value drift would be a problem. With digital, I would guess it would be the granularity based on the microcontroller's clock, or sample rate of the ADC it would probably need.