MAXQ7667 16-Bit RISC Microcontroller-Based Ultrasonic Distance-Measuring System

The MC33411 900 MHz Analog Cordless Phone Baseband system is designed to meet the specifications of a 900 MHz Analog cordless telephone system. It includes three Phase-Locked Loops (PLLs). Two of these PLLs are intended for use with external Voltage-Controlled Oscillators (VCOs) and 64/65 or 128/129 dual modulus prescalers, enabling control of the transmit and receive (LO1) frequencies for 900 MHz communication. The third PLL is configured as the second local oscillator (LO2) and operates at 80 MHz. Additional features include muting, audio gain adjustment (both internal and external), low battery carrier detection, and a broad range for the PLL reference frequency. The power supply operates within a range of 2.7 to 5.5 V. The A version devices have programmable microcontroller clock output and reference oscillator disable functions, while these features are always enabled in B version devices. This system is produced by Freescale Semiconductor, Inc.

The MC33411 is a sophisticated integrated circuit tailored for 900 MHz analog cordless telephone applications, featuring a robust architecture that supports essential functionalities for efficient communication. The three PLLs are a critical component of this system, allowing for precise frequency control necessary for both transmission and reception of signals within the designated frequency band.

The first two PLLs interface with external VCOs, which are crucial for generating the necessary frequencies for the cordless phone's operation. The use of dual modulus prescalers (64/65 or 128/129) allows for flexible frequency division, enhancing the ability to fine-tune the transmit and receive frequencies. This capability is essential for maintaining communication integrity and minimizing interference, which is particularly important in crowded frequency environments.

The third PLL, functioning as the second local oscillator (LO2) at 80 MHz, plays a vital role in down-converting received signals for further processing. This frequency is strategically chosen to optimize performance and ensure compatibility with standard communication protocols used in cordless phones.

Additional features such as muting and audio gain adjustment ensure that audio output can be managed effectively, providing users with clear sound quality while allowing for customization based on user preferences or environmental conditions. The inclusion of low battery carrier detection is a valuable feature that enhances user experience by alerting users to low power conditions, thus preventing unexpected disconnections during calls.

The operational power supply range of 2.7 to 5.5 V provides flexibility in power management, allowing the system to be integrated into various designs without the need for extensive modifications. The distinction between the A and B version devices, particularly regarding the programmable microcontroller clock output and the reference oscillator disable functions, allows for tailored implementations based on specific application requirements.

In summary, the MC33411 is a comprehensive solution for 900 MHz analog cordless phone systems, integrating multiple functionalities within a single package to streamline design and enhance performance in wireless communication applications.The MC33411 900 MHz Analog Cordless Phone Baseband system is designed to fit the requirements of a 900 MHz Analog cordless telephone system. Included are three PLLs (PhaseLocked Loops). Two are intended for use with external VCOs and 64/65 or 128/129 dual modulus prescalers, and CAN control the transmit and receive (LO1) frequencies for 900 MHz Co

mmunication The third PLL is configured as the 2nd local Oscillator (LO2), and is functional to 80 MHz. Also included are muting, Audio gain adjust (internal and external), low battery Carrier detect, and a wide range for the PLL reference frequency.

The power supply range is 2. 7 to 5. 5 V. A version devices have programmable MCU Clock out and reference Oscillator disable functions, whereas these functions are always enabled for B version devices. By Freescale Semiconductor, Inc 🔗 External reference