1.Features 1）Embedded EEPROM 。 Very Easy Development with RFPDK 。 All Features Programmable 2）Frequency Range: 240 to 960 MHz 3）FSK, GFSK and OOK Modulation 4）Symbol Rate: 。 0.5 to 100 ksps (FSK/GFSK) 。 0.5 to 40 ksps (OOK) 5）Deviation: 1.0 to 200 kHz 6）Output Power: -10 to +13 dBm 7）Sleep Current: < 20 nA 8）Stand-Alone, No External MCU Control Required 9）Embedded 1920, 1527 and 2262 Data Encoder 10）Up to 7 Configurable Data Pins for Push Buttons 11）LED Indicator for Low Battery Detection and Transmission 12）Sync ID Auto-Study with CMOSTEK Receiver 13）FCC / ETSI Compliant 14）RoHS Compliant 15）14-pin SOP Package
2.Descriptions The CMT2157A is a true single-chip, highly flexible, high performance, (G)FSK/OOK RF transmitter with embedded data encoder ideally for 240 to 960 MHz wireless applications. The device integrates a data encoder that is not only compatible with the most common used encoding format of 1527 and 2262, but also a more efficient, flexible and powerful format of 1920 designed by CMOSTEK. Up to 7 configurable push buttons are supported in multiple button modes. When pairing the device to CMOSTEK receiver, the synchronization ID can be programmed into both of the transmitter and receiver during the manufacturing phase, or studied by the receiver from the transmitter remotely by end customers. An embedded EEPROM allows the RF and encoder parameters to be programmed into the chip using the CMOSTEK USB Programmer and the RFPDK. Alternatively, in stock product of 868.35 MHz is available for immediate demands without the need of EEPROM programming. The CMT2157A is part of the CMOSTEK NextGenRFTM family, together with CMT225x series receivers, they enable ultra low cost, low power consumption RF links.
3.Applications 1）Low-Cost Consumer Electronics Applications 2）Home and Building Automation 3）Remote Fan Controllers 4）Infrared Transmitter Replacements 5）Industrial Monitoring and Controls 6）Remote Lighting Control 7）Wireless Alarm and Security Systems 8）Remote Keyless Entry (RKE)
More Ordering Info: See Page 26
Figure 1. CMT2157A Typical Application Schematic
Table 1. BOM of 433.92/868.35 MHz Typical Application
CMT2157A, 240 – 960 MHz (G)FSK/OOK stand-alone transmitter with encoder