SW
-
438
Functional Schematic
V 1.00
Features
Low Insertion Loss, 0.7 dB @ 2.4 GHz
1
High Isolation, 25 dB @ 2.4 GHz
1
Low Power Consumption, < 10 A @ +3 V
Low Cost Plastic SOT-363 Package
1. For best results at 2.4 GHz, use 8 pF 0402 profile SMT capaci-
tors on RF ports and 100 pF bypassing on pins 4 and 6.
Description
The SW-438 is a GaAs MMIC SPDT switch in a low cost
SOT-363 surface mount plastic package. Typical applica-
tions include transmit/receive switching for Bluetooth and
WLAN equipment. The SW-438 can also be used in applica-
tions up to 500 mW in systems such as cellular, PCS,
DCS1800, GSM, CDMA and other analog and digital wire-
less communications systems.
M/A-COM fabricates the SW-438 using a 0.5 micron gate
length GaAs p-HEMT process. The process features full pas-
sivation for increased performance and reliability.
GaAs SPDT Switch
DC 3.0 GHz
RF1 GND RF2
V1
RFC
V2
PIN 1
C
39pF
C
39pF
C
39pF
C=100pF
C=100pF
Broad Band Applications
RF1 GND RF2
V1
RFC
V2
PIN 1
C=8pF
C=8pF
C=8pF
C=100pF
C=100pF
2.4 GHz Application
External Component Requirements
Please note the values of the external capacitors. The ca-
pacitors at each of the RF ports are used as for achieving
optimum insertion loss. They also provide DC blocking for
positive control. The 8 pF (0402) capacitor is recom-
mended
for 2 - 3 GHz operation. If this value is changed or
the capacitor placed too far from the
switch, the
perform-
ance will be affected. We also recommend 100 pF bypass
capacitors on pins 4 and 6.
For broadband applications with positive control voltages,
use DC blocking capacitors with value of 39 pF or more
.
Pin Configuration
Pin No.
Function
Description
1
RF1
RF Input/Output
2
GND
RF Ground
3
RF2
RF Input/Output
4
V2
Control 2 Input
5
RFC
RF Common Port
6
V1
Control 1 Input
Ordering Information
Part Number
Package
SW-438TR-3000
SW-438 on 13 Inch, 3000 piece Reel
SW-438SMB
SW-438 sample test board
Mode
(Control)
V1
V2
RFC-RF1
RFC-RF2
Positive
1
0 + 0.2V
+2.3 to +5V
+2.3 to +5V
0 + 0.2V
Off
On
On
Off
Negative
2
0 + 0.2V
-2.3 to +5V
-2.3 to +5V
0 + 0.2V
On
Off
Off
On
Truth Table
1.
External DC blocking capacitors are required on all RF ports.
2.
If negative control is used, DC blocking capacitors are not required on RF ports.
GaAs SPDT Switch, DC-3.0 GHz
SW-438
Specifications subject to change without notice.
n
North America: Tel. (800) 366-2266
n
Asia/Pacific: Tel.+81-44-844-8296, Fax +81-44-844-8298
n
Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
Visit www.macom.com for additional data sheets and product information.
V 1.00
2
Typical Performance Curves
Bluetooth Applications
(
8 pF DC Blocking Capacitors, +2.3V Control)
Electrical Specifications: T
A
= 25C, 3V Control
Parameter
Test Conditions
Units
Min
Typ
Max
Insertion Loss
DC-3.0 GHz
dB
0.7
0.8
Isolation
DC-1.0 GHz
1.0-2.0 GHz
2.0-3.0 GHz
dB
dB
dB
29
23
21
31
25
23
Return Loss
DC-1.5 GHz
1.5-3.0 GHz
dB
dB
18
16
22
20
P1dB (2.3 V supply)
500 MHz-2.0 GHz
dBm
23
26
P1dB (3V supply)
500 MHz-2.0 GHz
dBm
28
31
IP2
2-tone 900 MHz, 5 MHz spacing (2.3V)
dBm
81
IP3
2-tone 900 MNz, 5 MHz spacing (2.3V)
dBm
55
2
nd
Harmonic
2.4 GHz Pin = 20 dBm, Vc = 2.3V
dBc
70
3
rd
Harmonic
2.4 GHz Pin = 20 dBm, Vc = 2.3V
dBc
60
Ton, Toff
50% ctl to 10/90% RF
ns
20
Trise, Tfall
10% to 90% RF
ns
10
Gate Leakage
|Vctl| = 5V
A
5
10
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
Frequency (GHz)
Insertion Loss (dB)
+25C
-40C
+85C
Insertion Loss vs. Frequency Over
Temperature
20
21
22
23
24
25
26
27
28
29
30
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
Frequency (GHz)
Isolation (dB)
+25C
-40C
+85C
Isolation
vs. Frequency Over Temperature
GaAs SPDT Switch, DC-3.0 GHz
SW-438
Specifications subject to change without notice.
n
North America: Tel. (800) 366-2266
n
Asia/Pacific: Tel.+81-44-844-8296, Fax +81-44-844-8298
n
Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
Visit www.macom.com for additional data sheets and product information.
V 1.00
Insertion Loss vs. Frequency Over Temperature
Broadband Applications
(No DC Blocking Capacitors, -2.3 V Control)
3
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Frequency (GHz)
Insertion Loss (dB)
+25C
-40C
+85C
Return Loss vs. Frequency Over Temperature
10
15
20
25
30
35
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Frequency (GHz)
Return Loss (dB)
+25C
-40C
+85C
20
25
30
35
40
45
50
55
60
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Frequency (GHz)
Isolation (dB)
+25C
-40C
+85C
Isolation vs. Frequency Over Temperature
Return Loss vs. Freqency Over Temperature
10
15
20
25
30
35
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
Frequency (GHz)
Return Loss (dB)
+25C
-40C
+85C
GaAs SPDT Switch, DC-3.0 GHz
SW-438
Specifications subject to change without notice.
n
North America: Tel. (800) 366-2266
n
Asia/Pacific: Tel.+81-44-844-8296, Fax +81-44-844-8298
n
Europe: Tel. +44 (1344) 869 595, Fax+44 (1344) 300 020
Visit www.macom.com for additional data sheets and product information.
V 1.00
Dimen-
sion
Min.
Nom.
Max.
A
--
--
1.10
A1
0
--
0.10
A2
0.70
0.90
1.00
b
0.15
--
0.30
c
0.08
--
0.22
L
0.42 ref.
Measurement (mm)
D
2.00 basic
e
0.65 basic
E
2.10 basic
E1
1.25 basic
SOT-363 (SC-70) Plastic Package
Note: See JEDEC MO-203 VAR AB for
Additional dimensions and tolerances.
PIN
1
PIN
6
D
e e
E
A
A1
b
c
L
A
E1
A2
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