LTC554x mixers satisfy needs of WiMAX basestations
Linear Technologycontact supplier
LTC554x mixers are designed to satisfy the requirements of nascent fourth-generation LTE cellular and WiMAX basestations, as well as 3G CDMA, WCDMA, TD-SCDMA, UMTS and GSM/EDGE platforms.
The series of four high-dynamic-range downconverting mixers covering the 700MHz to 4GHz wireless infrastructure frequency range.
The LTC554x mixers offer IIP3 (input third-order intercept) of 26dBm, low noise figures of 9-10dB and high conversion gain of 8dB, enabling high dynamic range performance for main receivers and digital predistortion receivers.
The mixers maintain a low noise figure in the presence of strong blocking interferers, enhancing receiver sensitivity and robustness.
The LTC554x range operates on a single 3.3V supply without compromising performance, while reducing power consumption by 34 per cent compared with the closest competing solution - according to the company.
The mixers' robust performance is said to enhance other wireless systems such as point-to-point microwave systems, cellular repeaters, public safety radios and military communication systems.
The LTC554x mixers contain an integrated IF amplifier, LO buffer, LO switch and RF balun transformers.
Each mixer's RF input is single ended, 50ohm matched.
Two single-ended LO inputs with high isolation are provided for frequency-hopping applications.
Each LO input is also single ended and always 50ohm matched regardless of whether the mixer is active or powered down to avoid unlocking of the PLL (Phased-Lock Loop).
The LO input requires only 0dBm drive level.
The LTC554x mixers have identical pinouts, allowing designers to share PC board layouts across multiple platforms operating in different frequency bands.
This helps users reduce total ownership costs and speed time to market.
The mixers' pinouts are also similar to common industry footprints and pinouts, allowing ease of adoption while improving performance and reducing power consumption.
The LTC554x mixers operate on a single 3.3V supply, drawing a supply current of 200mA.
The devices have a power-down feature with turn-on and turn-off time of 2us and 3us, respectively.
When disabled, the ICs consume a maximum of 500uA.
The products are offered in a 20-lead, 5 x 5mm QFN surface-mount package.
Linear Technology has introduced the LTC2933 programmable voltage supervisor with built-in EEPROM for the simultaneous, accurate monitoring of up to six voltage rails from 0.2V to 13.9V.
The LTC3624 is a high-efficiency, 17V-input-capable synchronous buck regulator from Linear Technology that delivers up to 2A of continuous output current to outputs as low as 0.6V. Synchronous rectification delivers efficiencies as high as 95 per cent, while Burst Mode operation requires only 3.5µA of no-load quiescent current.
The LT8471 from Linear Technology is a dual DC/DC converter that utilises two internal 2A, 50V switches and an additional 500mA switch to facilitate step-down, step-up and inverting conversion. Each 2A channel can be independently configured as a buck, boost, SEPIC, flyback, ZETA or inverting DC/DC converter. This range of topologies and output configurations makes the device suitable for industrial and automotive applications.
As Linear Technology’s Jim Williams explains, a large group of fibre-optic lasers are powered by DC current. Laser drive is supplied by a current source with modulation added further along the signal path. The current source, although conceptually simple, constitutes a tricky design problem. There are a number of practical requirements for a fibre-optic current source and failure to consider them can cause laser and/or optical component destruction.
Linear Technology has introduced the LTC6431-20: a 20MHz to 2GHz single-ended input and output fixed-gain amplifier that offers a 46.2dBm OIP3 (output third-order intercept) and a 2.6dB noise figure. Two grades are offered, including the A-grade version that has a minimum of 42.2dBm OIP3 at 240MHz and the B-grade version that has a typical OIP3 of 45.7dBm at the same frequency.