RF Transmitter Offers Low System Cost Implementation for Wireless Security, Home Automation Applications

The device operates on the 434 MHz, 869 MHz or 915 MHz license-free ISM (industry, scientific and medical) frequency bands. It supports data rates of between 1.2 kbps and 153.6 kbps. At the lowest data rate, the device is well suited for home appliance control applications such as garage door opener or home environmental remote controls. At higher speeds it can be used where more data needs to be transmitted such as in a wireless security camera that sends a video frame to a base station.
In addition, the device features an eight-step programmable power amplifier with a signal power range of 11dBm to 10dBm, allowing product developers to maximize battery life by customizing the power output for short-range indoor use or long-range outdoor applications.

The device comes in a 4mm x 4mm TQFN24 package and is highly integrated, which reduces the need for external components and results in a lower total system cost. ETSI and FCC regulations are satisfied without any need for a SAW filter. The small size and battery saving features also mean it can be used in ever smaller remote systems.

“Most of our customers have both legacy and next-generation projects underway and are challenged by the various RF issues they must solve for each, which is why we developed the SX1223 with design reuse in mind," said Robert Whittaker, ISM Product Group Manager for Semtech’s Wireless and Sensing Products Business Unit. "The device has the ideal ratio of size, functionality, low power consumption and low system cost to allow customers to take full advantage of the rapidly evolving market for wireless home automation and remote security products."

The high-efficiency SX1223 typically consumes only 25.8 mA @ 10dBm in transmitter mode and has a quiescent power draw of 300nA. The device has four operation modes (sleep, standby, synthesizer running and transmit) to further prolong battery life. A fast start-up mode wakes the device from sleep mode in less than 150µs, further saving battery life by shortening the time between being enabled and transmitting data.

The SX1223 is the first transmitter-only product to join Semtech’s wireless product line, and is fully compatible with the company’s XE1203F and XE1205 transceivers. These devices are two of the industry’s most sensitive ISM-band transceivers and, when combined with the SX1223, provide an extremely reliable and cost effective solution for unidirectional wireless systems.

The SX1223 is available immediately in production quantities and is priced at $1.45 each in 10,000-piece lots. The ordering code for the device is SX1223I073TRT. Semtech offers comprehensive design assistance, including field- and factory-based support. Data sheets, volume pricing, and delivery quotes, as well as evaluation kits and samples, are available by contacting salesinfo@semtech.com.