Microwave Diode and Capacitors - Cobham plc

Frequency Multiplier Diodes
Silicon Step Recovery Diodes
A snap varactor is a silicon epitaxial device designed to store charge when conducting in the forward direction.
Conduction continues for a short time under reverse bias until the stored charge is swept out by the reverse
drive. At this point conduction ceases very abruptly. Lifetime is a measure of the time the diode will maintain
the stored charge and the snap time (transition time) is the speed at which reverse conduction ceases.
These diodes find application in high efficiency multiplier and up/down converter applications and for comb
generators.
Specifications @ +25°C
Type
Number
Breakdown
Voltage
(V)
Capacitance
Cj-6 (pF)
Thermal
Resistance
(°C/W)
Minority Carrier
Lifetime (ns)
Snap Time
(ps)
Min Min Max Max. Min. Typ. Max. Typ.
Standard
Case
Style
ML4402 15 0.20 0.45 60 7 15 50 40 30
ML4404 15 0.20 0.45 60 10 20 100 70 30
ML4405 20 0.40 0.80 45 10 20 120 90 30
ML4406 30 0.70 1.2 35 15 30 150 100 30
ML4407 45 1.0 2.5 30 35 80 200 150 30
ML4408 60 2.0 4.0 25 50 150 500 350 30
ML4409 75 3.5 8.0 12 100 400 1500 600 30
Notes
1. Breakdown Voltage measured at I R = 10 µA
2. Junction Capacitance measured at f = 1 MHz
3. Minority carrier lifetime measured at I F = 10 mA
4. Thermal resistance measurement is based on an infinite heat sink.
5. Alternative case styles available on request.
6. Storage / Operating Temperature -65°C to +150°C
7. Power Dissipation = 150°C – T ambient
Thermal Resistance
Cobham MAL Ltd trading as Cobham Sensor Systems www.cobham.com/sensorsystems
© Cobham plc, 2010.
Whilst every effort is made to ensure the accuracy of the information contained in this brochure, no responsibility can be accepted for any errors and/or
omissions. Descriptions and specifications of products are subject to change without notice Page 2 of 37