TQM8M9077
0.05-4 GHz Digital Variable Gain Amplifier
Serial Control Interface
The TQM8M9077 has a CMOS SPITM input compatible serial interface. This serial control interface converts the serial data
input stream to parallel output word. The input is 3-wire (CLK, LE and SERIN) SPITM input compatible. At power up, the
serial control interface resets the DSA to the minimum gain state. The 6-bit SERIN word is loaded into the register on rising
edge of the CLK, MSB first. When LE is high, CLK is disabled.
SERIN (MSB in First 6-Bit Word) Control Logic Truth Table
Test conditions: 25ºC, Vdd = +5V
6-Bit Control Word to DSA
Gain Relative to
Maximum Gain
LSB
D5
1
MSB
D4
1
D3
1
D2
1
D1
1
D0
1
Reference : IL
0.5 dB
1 dB
1
1
1
1
1
0
1
1
1
1
0
1
1
1
1
0
1
1
2 dB
4 dB
1
1
0
1
1
1
1
0
1
1
1
1
8 dB
16 dB
31.5 dB
0
1
1
1
1
1
0
0
0
0
0
0
Any combination of the possible 64 states will provide a reduction in gain of
approximately the sum of the bits selected.
Serial Control Interface Timing Diagram
CLK is disabled when LE is high
Datasheet: Rev D 01-20-12
Disclaimer: Subject to change without notice
- 3 of 9 -
© 2012 TriQuint Semiconductor, Inc.
Connecting the Digital World to the Global Network®
TRIQUINT [ TRIQUINT SEMICONDUCTOR ]
