X3211 Datasheet, PDF (8/12 Pages) Unisonic Technologies – LINEAR INTEGRATED CIRCUIT

UTC X3211 LINEAR INTEGRATED CIRCUIT
the power input of the LNB via a high value (10k) resistor. With th input voltage of the LNB set at or below 14V.FET
Q2 will be enabled. With the input voltage at or above 15.5V,FET Q1 will be enabled.The disabled FET has its gate
driven to 0V and its drain terminal is switched open circuit.FET number Q3 is always active regardless of the voltage
applied to Vpol.
D1
Q1
G1
Drain
voltage&
Current
Controller
Enable
VPOL Input
-
+
D2
Q2
G2
20μA
VSUB
Drain
voltage&
Current
Controller
Enable
14.75V
Reference
D3
Q3
G3
20μA
VSUB
Drain
voltage&
Current
Controller
Enable
20μA
VSUB
Control input switch function
INPUT SENSE
<= <= ≤14 volts
≥15.5 volts
POLARISATION
Vertical
Horizontal
SELECT
FET Q2
FET Q1
For many LNB application tone detection and band switching is required.The X3211 includes the circuitry necessary
to detect the presence of a 22kHz tone modulated on the supply input to the LNB.Referrring to the following
schematic diagram,the main elements of this detector are an op-amp enabling the construction of a Sallen key
filter,a rectifier/smoother and a comparator.Full control is given over the center frequency and bandwidth of the filter
UTC UNISONIC TECHNOLOGIES CO., LTD. ⁸
QW-R122-004,C