CT	Rs	tau	VBR
Part Number	[pF]	[ohms]	[nsec]	[V]
HSMP-382x	0.8	0.6	70	35
HSMP-383x	0.3	1.5	500	200
HSMP-386x	0.25	4.5	unspecified	200
HSMP-388x	0.4	6.5	2500	100
HSMP-389x	0.3	2.5	200	35
HPND-4005	0.017	4.7	100	100
HPND-4028	0.045	3.0	36	60
HPND-4038	0.065	2.0	45	60
1N5719	0.3	1.25	100	150
5082-0001	0.16	0.8	35	70
5082-0012	0.3	1.5	500	200
5082-3001	0.25	1.0	100	200
5082-3039	0.25	1.25	100	150
5082-3077	0.3	1.5	100	200
5082-3188	1.0	0.6	100	35

Glossary

What:

The total capacitance associated with the diode, equal to the junction capacitance Cj plus any other parasitic capacitance such as package parasitic capacitance.

Goodness:

lower is better

Low capacitance is required for good isolation in a series switch.

Low capacitance also implies a low loss switch in the shunt configuration.

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Series Resistance of a PIN Diode (R_s)

What:

At RF frequencies a PIN diode with forward bias behaves essentially as a pure resistor, called R_s. The value of R_s is related to the bias current, the geometry of the I layer, and the properties of the carriers.

Goodness:

lower is better

Low resistance gives low insertion loss for a series switch.

Low resistance also gives better isolation in a shunt switch.

Low resistance is needed for best reflection, hence best isolation, in limiter (ideal is 0 ohms).

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Carrier Lifetime ()

What:

An important parameter a PIN diode is the carrier lifetime, , which is useful for defining the low frequency limit f_o = 1/2, for linear performance of the diode. For RF signals below f_o, the PIN diode rectifies the signal much like an ordinary PN junction diode, and considerable output distortion results. At frequencies above f_o less rectification occurs with increasing frequency, allowing the PIN diode to appear more linear, approaching a pure resistor.