AD8347-EVAL Analog Devices Inc, AD8347-EVAL Datasheet - Page 17

• Manufacturer Part Number: AD8347-EVAL
• Description: BOARD EVAL FOR AD8347
• Manufacturer: Analog Devices Inc

Specifications of AD8347-EVAL

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

these networks with staggered RC constants. Each branch goes
through a buffer to make up for the loss and high frequency
roll-off. The output from the buffers then goes into another
polyphase phase splitter to enhance the accuracy of phase
quadrature. Each LO signal is buffered again to drive the
mixers.
OUTPUT LEVEL DETECTOR
To create an AGC voltage (VAGC), two signals proportional to
the square of each output channel are summed together and
compared to a built-in threshold. The inputs to this rms
detector are referenced to VREF.
Rev. A | Page 17 of 28
BIAS
An accurate reference circuit generates the reference currents
used by the different sections. The reference circuit is controlled
by an external power-up (ENBL) logic signal that, when set low,
puts the whole chip into a sleep mode typically requiring less
than 400 μA of supply current. The reference voltage (VREF) of
1.0 V, that serves as the common-mode reference for the
baseband circuits, is made available for external use. The VREF
pin should be decoupled with a 0.1 μF capacitor to ground.
AD8347