Rf Port Interface Information; Transmit Ports: Tx1± And Tx2; Receive Ports: Rx1A±, Rx1B±, Rx2A±, And Rx2B; External Local Oscillator Ports: Lo1± And Lo2 - Analog Devices ADRV9005 Reference Manual

Reference Manual

RF PORT INTERFACE INFORMATION

The RF ports of the ADRV9001, consisting of the transmit (TX1±, TX2±) and receive ports (RX1A±, RX1B±, RX2A±, and RX2B±), support an
operational frequency range from 30 MHz to 6 GHz. This wide frequency range fulfills the requirements of many application spaces. However,
for optimized performance within a narrowband with minimal amplitude roll-off and optimized linearity and noise performance, the RF ports are
impedance-matched.
This section provides some examples of impedance matching networks to select frequency bands. Locating a balun/transformer to cover the
entire frequency range of the ADRV9001 with minimal phase and amplitude imbalance is a challenging task given the limited selection of
commercially available baluns. So, the example RF matching networks are chosen based on the available baluns/transformers and RF trace
implementations on the evaluation PCB.
The matching networks are divided into two categories, wideband and narrowband. The wideband matching networks cover a range of almost 3
GHz and possess more amplitude roll-off compared to the narrowband match. This roll-off is often dominated by the characteristic performance
of the balun/transformer. For more optimized performance within a narrowband, use the frequency-specific narrowband matches.
TRANSMIT PORTS: TX1± AND TX2±
The ADRV9001 uses a direct conversion transmitter architecture consisting of two identical and independently controlled transmitter channels.
The differential output impedance of transmitter outputs is matched to 50 Ω, as shown in
a low noise 1.8 V supply.
RECEIVE PORTS: RX1A±, RX1B±, RX2A±, AND RX2B±
The ADRV9001 has two RF inputs for each receiver to accommodate different matching for each RF band of interest. The mixer architecture is
very linear and inherently wideband, which facilitates wideband impedance matching. The differential input impedance of the receiver inputs is
100Ω, as shown in Figure 243
When selecting a balun/transformer for the receive paths, use a 2:1 impedance transformation to accommodate the 50 Ω single-ended
impedance to 100 Ω differential impedance, as required by the ADRV9001 receiver inputs.
The receiver input pins are self-biased internally to 650mV and, therefore, require AC-coupling/DC-blocking capacitors at their inputs.
EXTERNAL LOCAL OSCILLATOR PORTS: LO1± AND LO2±
Apply two external LO inputs (LO1 and LO2) to the ADRV9001, and use each external LO signal for any of the two receivers or two transmitters
instead of an internally generated LO signal. The AC-coupling interface is needed for both the positive and negative sides of the external
LO input pins, which are internally biased. Similar to the receiver RF interface, a balun with 2:1 impedance transformation is necessary to
accommodate the 50 Ω single-ended impedance to 100 Ω differential impedance, as required by the ADRV9001 external LO inputs.
DEVICE CLOCK PORT: DEV_CLK1±
There are two low-frequency (below 100 MHz) clock interface modes and an LVDS-type clock interface mode that can support the clock signal
running as fast as 1 GHz. For the high-frequency clock interface, off-chip 100 Ω resistive termination is required, along with AC-coupling caps.
The subsequent section Connection for External Device Clock (DEV_CLK_IN)

RF RECEIVER/TRANSMITTER PORTS IMPEDANCE DATA

This section provides the port impedance data for all the transmitters and receivers in the ADRV9001 integrated transceiver. Note the following:
The ADRV9001 ball pads are the reference plane for this data.
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Single-ended mode port impedance data is not available. However, a rough assessment is possible by taking the differential mode port
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impedance data, and dividing the real and imaginary components by two.
Contact Analog Devices Applications Engineering for the impedance data in the Touchstone format.
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and Figure 244.
Figure 242. Additionally, bias the transmitter outputs to
provides more information.
ADRV9001
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