Analog Devices Inc. ADL5373ACPZ-R7

Overview

ADL5373ACPZ-R7 from Analog Devices is a fixed-gain quadrature modulator IC operating from 2300 MHz to 3000 MHz, designed for direct RF upconversion in broadband wireless transmitters. It accepts differential I/Q baseband inputs (1.4 V_p-p, 500 mV dc bias), mixes with a differential LO, and delivers a single-ended RF output with 7.1 dBm typical power at 2500 MHz, 26 dBm OIP3, and −157.1 dBm/Hz noise floor - enabling high-efficiency WiMAX and satellite modem signal generation.

For engineers reviewing the ADL5373ACPZ-R7 datasheet, ADL5373ACPZ-R7 pinout, ADL5373ACPZ-R7 application, or ADL5373ACPZ-R7 equivalent, key selection criteria include its 500 MHz 3 dB baseband bandwidth, −57 dBc sideband suppression at 2500 MHz, carrier feedthrough of −32 dBm, 24-lead LFCSP package with exposed paddle, and compatibility with Analog Devices TxDACs such as AD9779 for zero-IF architectures.

Technical Context

The ADL5373ACPZ-R7 implements a silicon-germanium bipolar architecture with integrated polyphase LO quadrature splitter, limiting amplifiers, Gilbert-cell I/Q mixers, and an on-chip balun for differential-to-single-ended conversion. Its V-to-I baseband interface requires precise 500 mV dc common-mode bias and supports >500 MHz baseband bandwidth while maintaining <0.3° quadrature error and 0.06 dB I/Q amplitude balance at 2500 MHz.

LO input is differential (−6 dBm to +6 dBm drive), baseband inputs are high-impedance (40 kΩ || 1.5 pF), and RF output at Pin 13 is single-ended with internal 50 Ω reference impedance - requiring external ac-coupling and optional matching per S22 characteristics. Power delivery uses five dedicated 4.75–5.25 V supply pins (VPS1–VPS5) with 174 mA total current draw.

Key Specifications

Pinout & Package

ADL5373ACPZ-R7 is housed in a 24-lead, 4 mm × 4 mm, exposed-paddle Pb-free LFCSP (Lead Frame Chip Scale Package). The exposed paddle must be soldered to a low-impedance ground plane using ≥9 vias for optimal thermal and RF performance. Pin numbering follows top-view orientation with Pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quadrature modulator applications.

Compared with ADL5372ACPZ-R7 and TRF3705IRGZT, the ADL5373ACPZ-R7 uniquely delivers 2300–3000 MHz coverage with integrated LO quadrature generation, on-chip balun, and superior sideband suppression - making it the only drop-in solution for 2.5 GHz WiMAX and S-band satellite uplink designs requiring minimal external circuitry.

Availability

ADL5373ACPZ-R7 is available at Aetrix Electronics and suitable for WiMAX base station transmitters, satellite modem uplinks, broadband wireless CPE, and RF test equipment requiring stable component supply, full traceability, and long-term lifecycle support.

Supply support for ADL5373ACPZ-R7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and RF ICs, headquartered in Norwood, MA, with design centers worldwide and manufacturing in advanced SiGe and CMOS processes.

The ADL5373ACPZ-R7 belongs to Analog Devices' fixed-gain quadrature modulator (F-MOD) family, engineered specifically for broadband zero-IF and low-IF RF upconversion in wireless infrastructure - emphasizing phase accuracy, amplitude balance, and integration to replace discrete modulator solutions.

FAQ

What is the recommended LO drive level for ADL5373ACPZ-R7?

The ADL5373ACPZ-R7 specifies optimal performance at 0 dBm differential LO drive, with allowable range from −6 dBm to +6 dBm. Increasing LO power to +6 dBm improves noise floor by ~0.5 dB but does not affect OIP3 or P1dB. At −6 dBm, sideband suppression degrades by ≤2 dB and carrier feedthrough increases by ~3 dB - still within usable limits for many applications. The recommended balun is Johanson Technology 2450BL15B050.

How do I bias the baseband inputs of ADL5373ACPZ-R7 correctly?

The ADL5373ACPZ-R7 baseband inputs (IBBP/IBBN/QBBP/QBBN) require a precise 500 mV dc common-mode bias and are not self-biased. A nominal 1.4 V_p-p differential ac signal (700 mV_p-p per pin) is specified. Bias is typically established using 50 Ω resistors to ground from each DAC output (e.g., AD9779), yielding 500 mV with 10 mA average current. The dc bias range is 400–600 mV; deviation reduces usable ac swing and may degrade I/Q balance.

Does ADL5373ACPZ-R7 require external filtering on the RF output?

The ADL5373ACPZ-R7 does not require mandatory external filtering, but system-level spectral purity often demands it. Its inherent sideband suppression (−57 dBc) and harmonic levels (−47 dBc third harmonic at 2500 MHz) meet baseline requirements; however, FCC/ETSI spectral masks for WiMAX or satellite uplinks typically necessitate additional bandpass filtering after VOUT to suppress harmonics and out-of-band noise. The internal balun drives 50 Ω loads, so matching networks may be needed depending on PA input impedance.

Can ADL5373ACPZ-R7 be used below 2300 MHz or above 3000 MHz?

No - the ADL5373ACPZ-R7 is characterized and guaranteed only from 2300 MHz to 3000 MHz. Performance outside this band is not specified: output power drops >3 dB below 2300 MHz and >4 dB above 3000 MHz; sideband suppression degrades beyond −45 dBc; and OIP3 falls below 22 dBm. For 300–2000 MHz, use ADL5372ACPZ-R7; for 300–4000 MHz coverage with reconfigurable gain, consider ADL5375ACPZ-R7 instead.

What thermal management is required for ADL5373ACPZ-R7 in continuous operation?

ADL5373ACPZ-R7 dissipates ~870 mW (5 V × 174 mA) and has θ_JA = 54°C/W when the exposed paddle is soldered to a 4-layer PCB ground plane with ≥9 thermal vias. To maintain junction temperature ≤125°C at +85°C ambient, minimum copper area under the package should be 120 mm². Application Note AN-772 details thermal pad layout, via placement, and solder stencil recommendations - omitting proper paddle grounding risks >30°C temperature rise and degraded I/Q performance.