Reference design integrates Semtech ISM-band transmitter and transceivers with Microchip KEELOQ encryption software and PIC Microcontrollers to provide a high-performance, RKE platform.
Semtech Corp. and Microchip Technology Inc. announced the availability of a reference design that provides a turnkey platform for highly secure, low-power, multi-band wireless remote keyless entry (RKE) systems. This new reference design integrates Semtech’s high-performance transmitter and transceiver ICs with Microchip’s KEELOQ code-hopping technology running on PIC microcontrollers (MCUs). It is designed to simplify and accelerate the development of secure, high-performance and cost-effective RKE systems for vehicles, office buildings and homes, and provides a single platform that works across virtually all major frequency regulations.
The RKE reference-design hardware includes transmitter (Tx) and receiver (Rx) boards running Microchip’s KEELOQ code-hopping encryption software and Microchip MCUs. The Tx board pairs Semtech’s SX1230 industrial, scientific and medical (ISM) band transmitter with Microchip’s PIC16F631 or PIC16F677 8-bit MCUs. The Rx board employs Semtech’s SX1211 or SX1212 ISM transceivers, again with Microchip’s PIC16F631 or PIC16F677 MCUs.
The SX1230 is a multi-band ISM transmitter that complies with virtually all major country-specific radio regulations. It is fully configurable and dynamically programmable for narrowband and wideband applications in the 315, 434, 868 and 915 MHz license-free ISM frequency bands, and works with FSK, GFSK, MSK, GMSK and OOK modulation formats up to 600 kb/s, with constant RF performance over the 1.8V to 3.7V operating range. The device features 30 mA current consumption at +10dBm output power and 500 nA sleep mode current for increased battery life. RF output power is programmable up to +17 dBm in 1 dB steps from -20 dBm.
The SX1210/SX1211/SX1212/SX1213 family offers a broad range of pin-to-pin compatible ISM-band transceivers and receivers, covering all worldwide unlicensed bands from 300 MHz to 510 MHz and from 863 MHz to 960 MHz. The key strength of this family is its outstanding receiver (Rx) current consumption of less than 3 mA, while providing high bit rates of more than 150 kbps, along with a state-of-the-art packet engine and complete flexibility via register programming.
This new RKE reference design kit uses Microchip’s KEELOQ code-hopping technology running on Microchip’s PIC microcontrollers. The KEELOQ security algorithm encrypts information in the RF transmission packets before they are transmitted, unlike some existing RKE systems in the market. This solution from Semtech and Microchip stores confidential information inside the Flash memory of the PIC microcontroller and then encrypts it inside each data packet, prior to any RF transmission.
Additionally, the KEELOQ code-hopping algorithm creates a unique transmission on each activation of the transmitter, rendering replay attacks useless. The combination of a 64-bit key length and KEELOQ code-hopping technology significantly reduces the possibility of unwanted access or security breaches.
The PIC16F631 (1.75 KB Flash, 128B EEPROM) and PIC16F677 (3.5 KB Flash, 256B EEPROM) are 20-pin, 8-bit, Flash PIC MCUs that are available in a small 4x4 mm QFN package. Standard on-chip peripherals include an 8 MHz internal oscillator, an analog comparator module with two comparators, up 12 channels 10-bit ADC, and a programmable on-chip voltage reference. With an operating voltage of 2.0-5.5V, various reset and power saving options, these MCUs provide everything required for a low-power, robust and reliable design. The KEELOQ system supports up to 16 Semtech Tx units on a single receiver using the PIC16F631 MCU, or up to 32 Tx units using the PIC16F677 MCU.
“Our relationship with Microchip means we can now provide a highly secure, turnkey RKE reference solution integrating the industry’s highest performing microcontrollers and RF ICs, along with leading security encryption software,” said Sameer Vuyyuru, Semtech Vice President Marketing for Semtech’s Advanced Communications and Sensing Group. “RKE designers now have a reference solution that does not require specialized RF design or encryption programming skills, compared to discrete or analog RF integrated circuit approaches that require security software and RF engineering expertise, and involve long design cycles with extensive production stabilization efforts.”
“This new RKE reference platform offers a strategic combination of security along with high-performance, low-power processing and RF transmission,” said Vivien Delport, director of Applications for Microchip’s Security, Microcontroller & Technology Development Division. “Semtech brings the high-performance transmitters and receivers that, when integrated with our KEELOQ code-hopping technology and PIC microcontrollers, results in RKE systems that are easy to design, secure, low power, cost effective and easily adaptable to multiple global standards.”
Key Features of the Semtech - Microchip Remote Keyless Entry (RKE) Reference Design
- Turnkey hardware and software RKE reference design, including:
- Hardware: integrated RF ICs, multi-band PCB antenna, MCU
- Software: KEELOQ code-hopping technology software
- Highly secure:
- Encrypts all RF packets before sending, no plain text sent over air
- Code-hopping encryption produces unique RF transmission each time.
- Saves design cost and time -- same design supports multi-band (315, 434, 868, 915 MHz) and multiple modulation formats (FSK, OOK, ASK)
- No tuning for lower production costs
- Long range: programmable POUT up to +17 dBm
