1N5817 1N5818 1N5819
NOTE 4 — HIGH FREQUENCY OPERATION
Since current flow in a Schottky rectifier is the result of majority carri-
er conduction, it is not subject to junction diode forward and reverse re-
covery transients due to minority carrier injection and stored charge.
Satisfactory circuit analysis work may be performed by using a model
consisting of an ideal diode in parallel with a variable capacitance. (See
Figure 10.)
Rectification efficiency measurements show that operation will be
satisfactory up to several megahertz. For example, relative waveform
rectification efficiency is approximately 70 percent at 2.0 MHz, e.g., the
ratio of dc power to RMS power in the load is 0.28 at this frequency,
whereas perfect rectification would yield 0.406 for sine wave inputs.
However, in contrast to ordinary junction diodes, the loss in waveform
efficiency is not indicative of power loss: it is simply a result of reverse
current flow through the diode capacitance, which lowers the dc output
voltage.
200
C, CAPACITANCE (pF)
100
70
50
30
20
TJ = 25°C
f = 1.0 MHz
1N5817
1N5818
1N5819
10
0.4 0.6 0.8 1.0
2.0
4.0 6.0 8.0 10
VR, REVERSE VOLTAGE (VOLTS)
20
40
Figure 10. Typical Capacitance
Rectifier Device Data
5
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