2 - 44
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
A
TTENU
A
T
ORS
2
SMT
GaAs MMIC SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
Features
The HMC235QS16G is a broadband 5-bit
digital attenuator in a 16 - lead (narrow
pitch) surface mount QSOP plastic pack-
age with an exposed ground slug. This
package occupies the same area as an 8
lead SOIC package. The 1, 2, 4 and 8 dB
bits have less than 10 degrees relative
phase shift. The five primary attenuation
states can be activated independently, or
collectively for attenuation levels of 1 to 31
dB. The HMC235QS16G is ideal for cellu-
lar, PCS, WLL, LMDS and IF
applications.This is the smallest 5 bit digi-
tal attenuator available.
General Description
WIDE BANDWIDTH: DC - 4 GHz
ATTENUATION BITS: 1, 2, 4, 8, 16 dB
MINIATURE QSOP-16 PACKAGE
Parameter
Frequency
Min.
Typ.
Max.
Units
Insertion Loss
DC- 2 GHz
2 - 4 GHz
5.0
5.3
5.4
6.0
dB
dB
Attenuation Range
DC- 4 GHz
25
31
dB
Input Return Loss (All States)
DC- 2 GHz
2 - 4 GHz
7
4
12
7
dB
dB
Output Return Loss (All States)
DC- 2 GHz
2 - 4 GHz
10
7
18
11
dB
dB
Attenuation Accuracy:
1 dB Bit
2 dB Bit
4 dB Bit
8 dB Bit
16 dB Bit
All Bits (31 dB)
0.1 - 2 GHz
0.5
1.4
3.2
7.0
14.0
26.0
1
2
4
8
16
31
1.5
2.6
4.8
9.0
17.9
35.0
dB
dB
dB
dB
dB
dB
Attenuation Accuracy:
1 dB Bit
2 dB Bit
4 dB Bit
8 dB Bit
16 dB Bit
All Bits (31 dB)
2 - 4 GHz
0.5
1.3
3.2
7.0
14.0
25.0
1
2
4
8
16
31
1.5
2.7
4.8
9.0
17.9
35.0
dB
dB
dB
dB
dB
dB
Switching Characteristics
tRISE, tFALL (10/90%)
tON, tOFF (50% CTL to 10/90% RF)
DC- 4 GHz
3
6
ns
ns
Input Power for 0.2 dB Compression
0.05 GHz Min. Atten. State
0.05 GHz All Atten. States
0.5 - 4 GHz Min. Atten. State
0.5 - 4 GHz All Atten. States
8
7
18
7
12
11
24
12
dBm
dBm
dBm
dBm
Input Third Order Intercept Point
each tone = +5dBm typ.
0.05 GHz Min. Atten. State
0.05 GHz All Atten. States
0.5 - 4 GHz Min. Atten. State
0.5 - 4 GHz All Atten. States
24
23
38
22
28
30
44
32
dBm
dBm
dBm
dBm
Guaranteed Performance
With 0/-5V Control, -40 to +85 deg C
HMC235QS16G
2 - 45
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
2
A
TTENU
A
T
ORS
SMT
HMC235QS16G SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
-7
-6
-5
-4
-3
-2
-1
0
0
0.5
1
1.5
2
2.5
3
3.5
4
I
N
SERTI
ON
LOSS
(
d
B)
FREQUENCY (GHz)
+85 C
-40 C
+25 C
-40
-30
-20
-10
0
0
0.5
1
1.5
2
2.5
3
3.5
4
I
N
PUT
R
ETURN
LOSS
(
d
B)
FREQUENCY (GHz)
REF. STATE
4 dB
16 dB
31 dB
0
10
20
30
40
50
60
70
0
0.5
1
1.5
2
2.5
3
3.5
4
PHASE
(
D
EGREES)
FREQUENCY (GHz)
8 dB
1, 2, 4 dB
16 dB
31 dB
-40
-30
-20
-10
0
0
0.5
1
1.5
2
2.5
3
3.5
4
O
U
T
P
UT
RET
URN
LO
SS
(
d
B)
FREQUENCY (GHz)
31 dB
REF. STATE
2 dB
4 dB
-35
-30
-25
-20
-15
-10
-5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
RELATI
VE
ATTENUATI
ON
(
d
B)
FREQUENCY (GHz)
8 dB
2 dB
1 dB
4 dB
16 dB
31 dB
Insertion Loss
Relative Phase
Output Return Loss
Relative Attenuation
Input Return Loss
-40
-30
-20
-10
0
0
0.5
1
1.5
2
2.5
3
3.5
4
O
U
T
P
UT
RET
URN
LO
SS
(
d
B)
FREQUENCY (GHz)
INPUT
RETURN LOSS
OUTPUT
RETURN LOSS
Input + Output Return Loss
(Reference State)
HMC235QS16G
2 - 46
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
A
TTENU
A
T
ORS
2
SMT
Input Power for 0.2 dB Compression
(Minimum Attenuation)
IP3 (Minimum Attenuation)
Input Power for 0.2 dB Compression
(Maximum Attenuation)
IP3 (Maximum Attenuation)
0
5
10
15
20
25
30
0
0.5
1
1.5
2
2.5
3
3.5
4
0
.
2
d
B
C
O
M
PRESSI
O
N
(d
Bm
)
FREQUENCY (GHz)
-40
O
C
+85
O
C
+25
O
C
0
5
10
15
20
25
30
0
0.5
1
1.5
2
2.5
3
3.5
4
0
.
2
d
B
C
O
M
PRESSI
O
N
(d
Bm
)
FREQUENCY (GHz)
-40
O
C
+85
O
C
+25
O
C
0
10
20
30
40
50
60
0
0.5
1
1.5
2
2.5
3
3.5
4
IP
3
(
d
B
m)
FREQUENCY (GHz)
-40
O
C
+85
O
C
+25
O
C
0
10
20
30
40
50
60
0
0.5
1
1.5
2
2.5
3
3.5
4
IP
3
(
d
B
m)
FREQUENCY (GHz)
-40
O
C
+85
O
C
+25
O
C
HMC235QS16G SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
HMC235QS16G
2 - 47
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
2
A
TTENU
A
T
ORS
SMT
Control Voltages
Control Voltage Range
+0.5 to -8.5 Vdc
Storage Temperature
-65 to +150 deg C
Operating Temperature
-40 to +85 deg C
RF Input Power (0.5 - 4 GHz)
Insertion Loss State
Any Attenuation State
+27 dBm
+13 dBm
State
Bias Condition
Low
0 to -0.2V@20uA Max
High
-3V@50uA Typ to -8V@500uA Max
Absolute Maximum Ratings
HMC235
4dB
1dB
2dB
8dB
16dB
A1 (16) B1 (15)
A2 (14)
A3 (13)
A4 (12) B4 (11) A5 (10) B5 (9)
RF2 (7)
GND
RF1 (2)
Pins 1, 3 - 6 and 8 are GND.
GND
GND
GND
GND
Schematic
Truth Table
t
u
p
n
I
l
o
r
t
n
o
C
t
t
A
t
e
S
t
i
B
B
d
4
B
d
1
B
d
2
t
i
B
B
d
8
t
i
B
B
d
6
1
1
A
1
B
2
A
3
A
4
A
4
B
5
A
5
B
i
H
o
L
i
H
i
H
i
H
o
L
i
H
o
L
f
e
R
i
H
o
L
o
L
i
H
i
H
o
L
i
H
o
L
B
d
1
i
H
o
L
i
H
o
L
i
H
o
L
i
H
o
L
B
d
2
o
L
i
H
i
H
i
H
i
H
o
L
i
H
o
L
B
d
4
i
H
o
L
i
H
i
H
o
L
i
H
i
H
o
L
B
d
8
i
H
o
L
i
H
i
H
i
H
o
L
o
L
i
H
B
d
6
1
n
o
i
t
a
u
n
e
t
t
a
n
a
e
d
i
v
o
r
p
l
l
i
w
s
e
t
a
t
s
e
v
o
b
a
f
o
n
o
i
t
a
n
i
b
m
o
c
y
n
A
.
d
e
t
c
e
l
e
s
s
t
i
b
e
h
t
f
o
m
u
s
e
h
t
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t
l
a
u
q
e
y
l
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t
a
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i
x
o
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p
p
a
HMC235QS16G SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
HMC235QS16G
2 - 48
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
A
TTENU
A
T
ORS
2
SMT
Suggested Driver Circuit
Bx
100pF
Ax
GaAs
ATTENUATOR
CONTROL
74HC04 (CMOS)
-5 VDC
10K
TTL
OR
CMOS
74HCT04 (TTL)
COMPENSATED
DEVICES
CD4689
Vz=5.1V
Izt=50uA
VCC
GND
GND
VCC
100pF
100
100
*
*
*
*
0.0256 (.65)
0.010 (0.025)
0.000/0.004
(0.00/0.10)
0.051/0.059 (1.30 / 1.50)
HMC235
YYWW
ZZZZ
EXPOSED GROUND SLUG
(CONNECT TO RF GROUND PLANE)
0.080 (2.03)
0.105
(2.67)
DATE CODE
YY = YEAR
WW = WEEK
0.228/0.224
(5.76/6.20)
LOT NUMBER
0.189/0.197
(4.80/5.00)
0.150/0.157
(3.81/3.99)
PIN 1
0.016 (0.41)
MIN TYP
0.004 / 0.010
(0.1 / 0.25)
TYP
0.044 0.015 (1.12 0.38)
PIN 1
0.037 0.015 (0.94 0.38)
Simple driver using inexpensive standard logic ICs provides fast switching using minimum DC current.
* Recommended values to suppress unwanted RF signals at Ax/Bx control lines. Component values may be
adjusted for switching speed considerations.
HMC235QS16G SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
Outline
1.
MATERIAL:
A) PACKAGE BODY - LOW STRESS INJECTION-MOLDED PLASTIC.
B) LEADFRAME AND SLUG MATERIAL: COPPER ALLOY
2 .
PLATING : LEAD - TIN SOLDER PLATE (LEAD AND SLUG)
3.
DIMENSIONS ARE IN INCHES (MILLIMETERS).
UNLESS OTHERWISE SPECIFIED ALL TOL. ARE 0.005(0.13).
4.
DIMENSION DOES NOT INCLUDE MOLDFLASH OF 0.15 MM PER SIDE
5.
DIMENSION DOES NOT INCLUDE MOLDFLASH OF 0.25 MM PER SIDE
HMC235QS16G
2 - 49
12 Elizabeth Drive, Chelmsford, MA 01824 Phone: 978-250-3343
Fax: 978-250-3373
Web Site: www.hittite.com
MICROWAVE CORPORATION
F
EBRUARY
2001
2
A
TTENU
A
T
ORS
SMT
HMC235QS16G SMT 5 - BIT DIGITAL ATTENUATOR DC - 4 GHz
The circuit board used in the final application should use RF circuit design techniques. Signal lines should have
50 ohm impedance while the package ground leads should be connected directly to the ground plane similar to
that shown above. A sufficient number of VIA holes should be used to connect the top and bottom ground planes.
The evaluation circuit board as shown is available from Hittite upon request.
Layout Technique
Grounded Co-Planar Waveguide (GCPW)
Material
Rogers 4350
Dielectric Thickness
0.020" (0.51 mm)
50 Ohm Line Width
0.034" (0.86 mm)
Gap to Ground Edge
0.010" (0.25 mm)
Ground VIA Hole Diameter
0.014" (0.36 mm)
Connectors
SMA-F ( EF - Johnson P/N 142-0701-806)
Evaluation Circuit Board
Evaluation Circuit Board Layout Design Details
HMC235QS16G
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