HMC271LP4 / 271LP4E
v03.0809
1 dB LSB GaAs MMIC 5-BIT SERIAL
CONTROL DIGITAL ATTENUATOR, 0.7 - 3.7 GHz
5
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
X
Reset
L
H
H
Function
Shift register cleared
Shift register clocked
Contents of shift register
transferred to Digital
Attenuator
FREQUENCY (GHz)
Timing
Symbol
Parameter
Min.
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)
ts
th
20
0
Max.
-
-
Min.
100
5
Max.
-
-
ns
ns
Vcc = +5V
Vcc = +3V
Units
Truth Table
Serial Data Input
C1
High
Low
High
tlsup
40
-
100
-
ns
High
High
High
tpd
-
30
-
70
ns
Low
-
fclk
20
-
-
30
50
-
-
10
ns
MHz
Low
Low
Low
Low
C2
High
High
Low
High
High
High
C4
High
High
High
Low
High
High
C8
High
High
High
High
Low
High
C16
High
High
High
High
High
Low
Attenuation
Setting
RF1 - RF2
Reference
I.L.
1 dB
2 dB
4 dB
8 dB
16 dB
31 dB
Max. Atten.
Any combination of the above states will provide an attenuation
approximately equal to the sum of the bits selected.
Timing Diagram
5 - 22
For price, delivery, and to place orders, please contact Hittite Microwave Corporation:
20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373
Order On-line at www.hittite.com
HITTITE [ HITTITE MICROWAVE CORPORATION ]
