ALPHA AS178-73 Datasheet

Alpha Industries, Inc. [781] 935-5150 • Fax [617] 824-4579 • Email [e-mail] • www.alphaind.com 1

Specifications subject to change without notice. 11/99A

PHEMT GaAs IC High Linearity Positive
Control SPDT Switch DC–2 GHz

Features

■ High Linearity (50 dBm IP3 @ 0.9 GHz)
@ 3 V

■ Low Insertion Loss (0.35 dB @ 0.9 GHz)

■ Isolation (21 dB @ 0.9 GHz)

■ +3 V Operation

■ Ultra Miniature SOT-6 Package

■ PHEMT Process

SOT-6

AS178-73

0.074

(1.90 mm REF.)

0.071 (1.80 mm)

0.052 (1.30 mm)

0.037 (0.95 mm) REF.

0.122 (3.10 mm)

0.106 (2.70 mm)

0.006

(0.15 mm)

0.000

(0.00 mm)

0.057 (1.45 mm)

0.035 (0.90 mm)

0.020 (0.51 mm)

0.014 (0.350 mm)

0.126 (3.20 mm)

0.087 (2.20 mm)

PIN 6

PIN 1

PIN 1

INDICATOR

0.022 (0.61 mm)

0.004 (0.10 mm)

0.014

(0.26 mm)

0.004

(0.10 mm)

0.012

(0.30 mm)

TYP.

5.0˚ ± 1˚

5.0˚ ± 1˚

Description

The AS178-73 is a PHEMT GaAs FET IC high linearity
SPDT switch in a SOT-6 plastic package. This switch has
been designed for use where extremely high linearity, low
insertion loss and ultra miniature package size are
required. It can be controlled with positive, negative or a
combination of both voltages. Some standard
implementations include antenna changeover, T/R and

Parameter

1

Frequency

2

Min. Typ. Max. Unit

Insertion Loss

3

DC–0.5 GHz 0.45 0.6 dB
DC–1.0 GHz 0.45 0.6 dB
DC–2.0 GHz 0.55 0.7 dB

Isolation DC–0.5 GHz 25 28 dB

DC–1.0 GHz 20 23 dB
DC–2.0 GHz 14 17 dB

VSWR

4

DC–1.0 GHz 1.2:1 1.4:1
DC–2.0 GHz 1.3:1 1.8:1

Electrical Specifications at 25°C (0, +3 V)

Preliminary

Parameter Condition Frequency Min. Typ. Max. Unit

Switching Characteristics

5

Rise, Fall (10/90% or 90/10% RF) 60 ns
On, Off (50% CTL to 90/10% RF) 100 ns
Video Feedthru 50 mV

Input Power for 1 dB Compression 0/+3 V 0.9 GHz +34 dBm

0/+5 V 0.9 GHz +38 dBm

Intermodulation Intercept Point (IP3) For Two-tone Input Power +17 dBm

0/+3 V 0.9 GHz +50 dBm
0/+5 V 0.9 GHz +57 dBm

Control Voltages V

Low

= 0 to 0.2 V @ 20 µA Max.

V

High

= +3 V @ 100 µA Max. to +5 V @ 200 µA Max.

VS= V

High

± 0.2 V

Operating Characteristics at 25°C (0, +3 V)

1. All measurements made in a 50 Ω system, unless otherwise specified.

2. DC = 300 kHz.

3. Insertion loss changes by 0.003 dB/°C.

4. Insertion loss state.

5. Video feedthru measured with 1 ns risetime pulse and 500 MHz bandwidth.

diversity switching over 2 W. The AS178-73 switch can be
used in many analog and digital wireless communication
systems including cellular, GSM and DECT applications.

PHEMT GaAs IC High Linearity Positive Control SPDT Switch DC–2 GHz AS178-73

2 Alpha Industries, Inc. [781] 935-5150 • Fax [617] 824-4579 • Email [e-mail] • www.alphaind.com

Specifications subject to change without notice. 11/99A

C

BL

C

BL

V

1

J

1

V

2

J

2

GND

J

3

C

BL

V

S

12 3

65 4

10 kΩ

Pin Out

V

1

V

2

J1–J

2

J1–J

3

0V

High

Isolation Insertion Loss

V

High

0 Insertion Loss Isolation

Truth Table

V

High

= +3 to +5 V (VS= V

High

± 0.2 V).

DC blocking capacitors (C

BL

) must be supplied externally.

C

BL

= 100 pF for operating frequency >500 MHz.

Typical Performance Data (0, +3 V)

Insertion Loss vs. Frequency

Frequency (GHz)

Insertion Loss (dB)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.0

0.5 1.0 1.5 2.0 2.5

VSWR vs. Frequency

Frequency (GHz)

VSWR

1.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2.0

0.0 0.5 1.0 1.5 2.0 2.5

Isolation vs. Frequency

Frequency (GHz)

Isolation (dB)

10

15

20

25

30

35

40

45

0.0 0.5 1.0 1.5 2.0 2.5

Characteristic Value

RF Input Power 10 W Max. > 900 MHz

0/+7 V Control

Control Voltage -0.2 V, +8 V

Operating Temperature -40°C to +85°C

Storage Temperature -65°C to +150°C

Θ

JC

25°C/W

Absolute Maximum Ratings