High Q Hyperabrupt
Tuning Varactors
Features
q
q
q
MA4ST550 Series
V3.00
Case Styles
q
High Q
Usable Capacitance Change of 7:1
Low Reverse Leakage for Good Post
Tuning Drift Characteristics
Reproducible C-V Curves
Description
The MA4ST550 family of high Q Silicon Hyperabrupt
Tuning Varactors is available in a series of low parasitic
capacitance microwave packages or in chip form.
The MA4ST550 series of diodes is available with junction
capacitances of approximately 0.8 pF to 8.2 pF at -4 volts.
These diodes have capacitance change ratios as high
as 7:1.
30
31
Applications
The MA4ST550 series is appropriate for use in VCOs with
frequencies within the range of approximately 1-14 GHz
where a large capacitance change is required. These
diodes are suited for VCOs in missile seekers, telecom-
munication systems and electronic warfare systems with
critical post tuning drift specifications.
134
Environmental Performance
All tuning varactors in ceramic packages are capable of
meeting the performance tests dictated by the methods
and procedures of the latest revisions of MIL-S-19500, MIL-
STD-202 and MIL-STD-750 which specify mechanical,
electrical, thermal and other environmental tests common
to semiconductor products.
Absolute Maximum Ratings at 25°C
Parameter
Reverse Voltage
Operating Temperature
Storage Temperature
Temperature Coefficient
Absolute Maximum
Same as Breakdown Voltage
- 65°C to +150°C
- 65°C to +200°C
400 ppm/°C at -4 Volts
Specifications Subject to Change Without Notice.
M/A-COM, Inc.
North America:
Tel. (800) 366-2266
Fax (800) 618-8883
s
1
Asia/Pacific: Tel. +81 (03) 3226-1671
Fax +81 (03) 3226-1451
s
Europe: Tel. +44 (1344) 869 595
Fax +44 (1344) 300 020
High Q Hyperabrupt Tuning Varactors
Electrical Specifications at 25°C
Breakdown Voltage = 22 Volts Minimum @ 10 Microamps
Reverse Current = 50 nAmps Maximum @ 20 Volts and 25°C
Model
Number
MA4ST551
MA4ST552
MA4ST553
MA4ST554
MA4ST555
MA4ST556
MA4ST557
MA4ST558
MA4ST559
MA4ST560
MA4ST561
MA4ST562
MA4ST563
Case
Style
30
30
30
30
30
30
30
30
30
30
30
30
30
1
MA4ST550 Series
V3.00
Total Capacitance
2,3
@ - 4V (pF)
Min./Max.
0.72-0.88
0.90-1.10
1.08-1.32
1.35-1.65
1.62-1.98
1.98-2.42
2.43-2.97
2.97-3.63
3.51-4.29
4.23-5.16
5.04-6.16
6.12-7.48
7.38-9.02
Total Capacitance
2,3
@ - 20V (pF)
Min./Max.
0.30-0.38
0.34-0.42
0.38-0.48
0.43-0.58
0.51-0.68
0.58-0.78
0.68-0.88
0.82-1.02
0.93-1.18
1.13-1.43
1.33-1.63
1.58-1.98
1.88-2.38
Typical
@ - 4 Volts
50 MHz
650
650
600
600
550
550
500
500
450
450
450
400
400
Notes:
1. The standard case style is 30. Other packages and chips shown at the
bottom of this page are available. When ordering, specify the desired
case style by adding the case designation as a suffix to the model
number, i.e. MA4ST552-134 is a 15 X 15 mil chip diode. See appendix
for complete dimensions.
2. Capacitance is measured at 1 MHz.
3. The total capacitance values shown are for devices housed in case
style 30. Other case styles will result in different values due to different
case parsasitics. Case parasitics (C
P
and L
S
) are given for available
case styles along with the outline drawings in the appendix.
Case Styles
30
31
94
120
134
1056
1088
Specifications Subject to Change Without Notice.
2
North America:
Tel. (800) 366-2266
Fax (800) 618-8883
s
M/A-COM, Inc.
Asia/Pacific: Tel. +81 (03) 3226-1671
Fax +81 (03) 3226-1451
s
Europe: Tel. +44 (1344) 869 595
Fax +44 (1344) 300 020
High Q Hyperabrupt Tuning Varactors
Typical Performance Curves
MA4ST550 Series
V3.00
CAPACITANCE vs REVERSE BIAS VOLTAGE
(CASE STYLE 30)
CAPACITANCE vs REVERSE BIAS VOLTAGE
(CHIPS)
Specifications Subject to Change Without Notice.
M/A-COM, Inc.
North America:
Tel. (800) 366-2266
Fax (800) 618-8883
s
3
Asia/Pacific: Tel. +81 (03) 3226-1671
Fax +81 (03) 3226-1451
s
Europe: Tel. +44 (1344) 869 595
Fax +44 (1344) 300 020
