The ALT1255 from Sony reduces cost for IoT connectivity by limiting features found in higher-end parts.
If you design wireless IoT devices, you focus on connectivity, battery life, and cost. While many IoT devices connect to LTE networks, LTE isn’t everywhere. Indeed 2G networks provide wider coverage than LTE and certainly more than 5G. Altair Sony’s ALT 1255 cellular IoT chipset integrates an LTE baseband processor, RF transceiver, memory, cellular based location engine, MCU
subsystem, and a hardware based integrated SIM (iSIM) into one package. It offers a 2G fallback for the many locations where LTE isn’t available.
The ALT1255 supports narrowband internet of things (NB-IoT) connectivity. The standard, found in 3GPP Release 13, specifies how low-speed devices connect in rural and deep-indoor locations where signal strength is often weak. The chipset also supports standards found in Release 14 and is software upgradable to Release 15. It supports the GSM-850, E-GSM-900, DCS-1800, and PCS-1900 2G frequency bands.
A scaled-down version of Sony’s ALT1250, the ALT 1255 reduces chipset cost by 20% to 30% when compared to its higher-end cousin. According to Dima Feldman of Sony Semiconductor Israel, the ALT1255 lacks support for Cat-M IoT and GNSS positioning. Less memory also reduces cost where the reduced latency and position monitoring found in Cat-M and GNSS aren’t needed.
Because IoT devices often include sensors for applications such as temperature monitoring, the ALT1255 includes I/O interfaces such as UART (3), SPI, pseudostatic random-access memory (PSRAM), UMTS Subscriber Identify Module (USIM), GPIO, I2C, AUX ADC, and PWM.
Feldman said that currently, most applications for the ALT1255 go into wireless connectivity modules, which is why the company has relationships with module makers Sierra Wireless, Murata, and Telit, to name a few. Although 95% of applications currently go into modules, Feldman expects the number chip-on-board designs to grow.