Analog Devices ADL5324 incorporates a dynamically adjustable biasing circuit that allows for the customization of OIP3 and P1dB performance from 3.3 V to 5 V, without the need for an external bias resistor. This feature gives the designer the ability to tailor driver amplifier performance to the specific needs of the design. This feature also creates the opportunity for dynamic biasing of the driver amplifier where a variable supply is used to allow for full 5 V biasing under large signal conditions, and then reduced supply voltage when signal levels are smaller and lower power consumption is desirable. This scalability reduces the need to evaluate and inventory multiple driver amplifiers for different output power requirements, from 25 dBm to 29 dBm output power levels.
The ADL5324 is also rated to operate across the wide temperature range of −40°C to +105°C for reliable performance in designs that experience higher temperatures, such as power amplifiers. The ½ W driver amplifier also covers the wide frequency range of 400 MHz to 4000 MHz, and only requires a few external components to be tuned to a specific band within that wide range. This high performance broadband RF driver amplifier is well suited for a variety of wired and wireless applications, including cellular infrastructure, ISM band power amplifiers, defense equipment, and instrumentation equipment. A fully populated evaluation board is available.
The ADL5324 also delivers excellent ACPR vs. output power and bias voltage. The driver can deliver greater than 17 dBm of output power at 2140 MHz, while achieving an ACPR of −55 dBc at 5 V. If the bias is reduced to 3.3 V, the −55 dBc ACPR output power only minimally reduces to 15 dBm.