HMC271ALP4 / 271ALP4E
v02.0311
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
Features
1 dB LsB steps to 31 dB
CMos Compatible serial Data Interface
sPI Compatible serial output
±0.4 dB typical Bit error
24 Lead 4x4mm QFn Package: 16mm²
Included in the HMC-DK004 Designer’s Kit
8
AttenuAtors - DIGItAL - sMt
Typical Applications
the HMC271ALP4(e) is ideal for:
• Cellular/3G Infrastructure
• Fixed Wireless, WiMax & WiBro
• test Instrumentation
Functional Diagram
General Description
the HMC271ALP4(e) is a broadband 5-bit positive
control GaAs IC digital attenuator with CMos com-
patible serial-to-parallel drivers in a low cost lead-
less QFn 4x4 mm sMt package. Covering 0.7 to
3.7 GHz, the insertion loss is typically less than 2.5
dB. the attenuator bit values are 1 (LsB), 2, 4, 8,
and 16 dB for a total attenuation of 31 dB. Accuracy
is excellent at ± 0.4 dB typical with an IIP3 of up to
+48 dBm. Five bit CMos compatible serial control
words are used to select each attenuation state. A
single Vcc bias of +3V to +5V applied through an
external 5 kohm resistor is required.
Electrical Specifications,
T
A
= +25° C, Vcc = +3V to +5V
Parameter
Frequency
0.7 - 1.4 GHz
1.4 - 2.3 GHz
2.3 - 2.7 GHz
2.7 - 3.7 GHz
0.7 - 3.7 GHz
0.7 - 1.4 GHz
1.4 - 2.7 GHz
2.7 - 3.7 GHz
0.7 - 0.9 GHz
0.9 - 2.2 GHz
2.2 - 3.7 GHz
Vcc = 5V
Vcc = 3V
Vcc = 5V
Vcc = 3V
0.7 - 3.7 GHz
0.7 - 3.7 GHz
Min.
typical
1.9
2.3
2.6
2.8
31
12
15
16
± (0.4 + 5% of Atten. setting) Max
± (0.4 + 4% of Atten. setting) Max
± (0.4 + 6% of Atten. setting) Max
24
22
48
46
Max.
2.4
2.8
3.1
3.3
units
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dBm
dBm
dBm
dBm
Insertion Loss
Attenuation range
return Loss (rF1 & rF2, All Atten. states)
Attenuation Accuracy: (referenced to Insertion Loss)
All Attenuation states
Input Power for 0.1 dB Compression
Input third order Intercept Point
(two-tone Input Power = 0 dBm each tone)
switching Characteristics
trIse, tFALL (10/90% rF)
ton, toFF (Latch enable to 10/90% rF)
0.7 - 3.7 GHz
750
830
ns
ns
8-1
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343
Fax: 978-250-3373
Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
HMC271ALP4 / 271ALP4E
v02.0311
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
Insertion Loss
0
-0.5
INSERTION LOSS (dB)
-1
-1.5
-2
-2.5
-3
-3.5
-4
0.5
+25C
+85C
-40C
Return Loss RF1, RF2
(Only Major States are Shown)
0
-5
RETURN LOSS (dB)
16 dB
-10
-15
-20
2 dB
-25
1 dB
-30
I.L.
2.5
3
3.5
4
4 dB
8 dB
31 dB
8
AttenuAtors - DIGItAL - sMt
8-2
1
1.5
2
2.5
3
3.5
4
0.5
1
1.5
2
FREQUENCY (GHz)
FREQUENCY (GHz)
Normalized Attenuation
(Only Major States are Shown)
0
NORMALIZED ATTENUATION (dB)
-5
Bit Error
vs. Attenuation State
2
1.5
0.9 GHz
BIT ERROR (dB)
1
0.5
0
-0.5
3.5 GHz
-1
1.9 GHz
2.4 GHz
-10
-15
-20
-25
-30
-35
0.5
1
1.5
2
2.5
3
3.5
4
0
4
8
12
16
20
24
28
32
FREQUENCY (GHz)
ATTENUATION STATE (dB)
Bit Error vs. Frequency
(Only Major States are Shown)
4
Relative Phase vs. Frequency
(Only Major States are Shown)
100
75
RELATIVE PHASE (deg.)
3
BIT ERROR (dB)
16 dB
8 dB
1, 2, 4 dB
50
25
0
-25
-50
-75
31 dB
2
16 dB
1
31 dB
0
1, 2, 4, 8 dB
-1
0.5
-100
1
1.5
2
2.5
3
3.5
4
0
0.5
1
1.5
2
2.5
3
3.5
4
FREQUENCY (GHz)
FREQUENCY (GHz)
Note: All Data Typical Over Voltage (+3V to +5V) & Temperature (-40°C to +85°C).
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343
Fax: 978-250-3373
Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
HMC271ALP4 / 271ALP4E
v02.0311
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
8
AttenuAtors - DIGItAL - sMt
Worst Case Step Error
Between Successive Attenuation States
1.2
0.8
STEP ERROR (dB)
0.4
0
-0.4
-0.8
-1.2
0.5
Digital Control Voltages
state
Low
High
Vcc = +5V
0 to 1.3V
3.5 to 5V
Vcc = +3V
0 to 0.7V
2.3 to 3V
Serial Input Truth Table
Latch
enable
X
X
1
1.5
2
2.5
3
3.5
4
shift
Clock
X
á
X
reset
L
H
H
Function
shift register cleared
shift register clocked
Contents of shift register
transferred to Digital
Attenuator
á
FREQUENCY (GHz)
Timing
Parameter
serial Input setup
time
Hold time from serial
Input to shift Clock
setup time from
shift Clock to Latch
enable
Propagation delay,
Latch enable to C1
through C16
setup time from
reset to shift Clock
Clock Frequency
(1/tclk)
symbol
Vcc = +5V
Min.
ts
th
20
0
Max.
-
-
Vcc = +3V
Min.
100
5
Max.
-
-
ns
ns
units
Truth Table
serial Data Input
C1
High
Low
High
tlsup
40
-
100
-
ns
High
High
High
tpd
-
30
-
70
ns
Low
C2
High
High
Low
High
High
High
Low
C4
High
High
High
Low
High
High
Low
C8
High
High
High
High
Low
High
Low
C16
High
High
High
High
High
Low
Low
Attenuation
setting
rF1 - rF2
reference
I.L.
1 dB
2 dB
4 dB
8 dB
16 dB
31 dB
Max. Atten.
-
fclk
20
-
-
30
50
-
-
10
ns
MHz
Any combination of the above states will provide an attenuation
approximately equal to the sum of the bits selected.
Timing Diagram
8-3
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343
Fax: 978-250-3373
Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
HMC271ALP4 / 271ALP4E
v02.0311
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
Logic / Functional Diagram
8
AttenuAtors - DIGItAL - sMt
Programming Example to Select 1 dB Attenuation State
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343
Fax: 978-250-3373
Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
8-4
HMC271ALP4 / 271ALP4E
v02.0311
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
8
AttenuAtors - DIGItAL - sMt
Pin Descriptions
Pin number
1, 3, 4, 6, 10, 12, 13,
15, 16, 18
Function
Description
these pins are not connected internally. However, all data
shown herein was measured with these pins connected
to rF/DC Ground.
this pin is DC coupled and matched to 50 ohms
Blocking capacitors are required. select value based on
lowest frequency of operation.
Interface schematic
n/C
2, 17
rF1, rF2
5
serial output
serial data output. serial input data
delayed by 8 clock cycles.
7
reset
see truth table, control voltage table and timing diagram.
8
shift Clock
9
Latch enable
11
serial Input
14
Vcc
supply Voltage.
Package bottom has an exposed metal paddle that must also
be connected to rF/DC Ground.
19 - 24
GnD
8-5
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: 978-250-3343
Fax: 978-250-3373
Order On-line at www.hittite.com
Application Support: Phone: 978-250-3343 or apps@hittite.com
