英語 での Reverse current の使用例とその 日本語 への翻訳
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True Shutdown disconnects the output from the input with no forward or reverse current.
This will work, as long as you isolate the MAX4895E's VCC pin with a diode to prevent reverse current flow.
There is also a low-side sinking current limit which turns off the low-side MOSFET to prevent excessive reverse current.
The MAX14819 integrates two low-power sensor supply controllers with advanced current limiting, reverse current blocking, and reverse polarity protection capability to enable low-power robust solutions.
Ultra-high-speed devices have high VF values, but because the reverse current IR is low, they experience low losses in continuous current mode of PFC(power factor correction) applications, to which they are well suited.
They can tolerate up to 5 V of noise spiking on the ground line and can handle up to 0.5 A of reverse current on the driver outputs.
From the standpoint of current paths, these external FRDs are not needed, but the internal diode of a MOSFET does not have a very fast trr, and so the reverse current Irr during this time trr results in a large loss.
For a Si FRD, as the temperature rises the carrier concentration increases, and more time is accordingly required for reverse recovery; the reverse current and trr are both larger relative to the values at room temperature.
Reverse-Biased Diode Basics After inspecting the diode equation presented in Equation 1, one might assume that a reverse-biased diode draws a reverse current IR equal to IS.
The device also provides high reverse blockage(low reverse current) and ground pin current that is nearly constant over all values of output current. .
Based on this rule and a reference point, we can use Equation 3 to calculate reverse current relative to temperature: I0 is the reverse current as specified at temperature T0.
The synchronous type sustains regulated operations by maintaining a continuous inductor current, albeit some decline in efficiency due to the fact that the reverse current flows are supplied from the output capacitor.
However, in AC/DC conversion, the diode reverse voltage is high and a large reverse current flows, and so discontinuous mode, in which a reverse current does not flow and losses are reduced, is generally used.
The ICs take ultra-low quiescent current and have what Maxim calls True ShutdownTM that disconnects the output from the input with no forward or reverse current.
Schemes to avoid this are possible by forcing CCM with variable frequency modes or even detecting the reverse current flow through the MOSFET and cutting its drive.
In low-voltage switching DC/DC conversion, the reverse voltage of the rectifying diode is low and the reverse current is also small, and so generally the continuous mode is used, giving priority to reducing the output ripple voltage and harmonics.
Finally, we have up till now said that almost no reverse current flows in an SiC SBD, but in the waveform diagram, it is clear that the current is much smaller than in an Si FRD, but is not zero.
Diodes D1 and D2 prevent reverse current from flowing between inputs via the"System Load" power path, while the charger has built-in circuitry to prevent reverse current through the charging path at BATT.
If the device is operated in a continuous mode, the reverse current that flows during the reverse recovery time trr of the diode causes diode losses to increase, and moreover the reverse current may reach the peak current while the MOSFET is ON, thus also increasing MOSFET losses.
Differences in Reverse Recovery Characteristics of SiC SBDs and Si PNDs First, the reader should already know that reverse recovery refers to a phenomenon in which, when a diode has entered a reverse-biased state, it does not immediately turn off completely, and a reverse current flows for a time, and that trr is this time in which the reverse current is flowing.