Vocoder for professional two-way radio

28 November 2012 Analogue, Mixed Signal, LSI

CML Microcircuits has expanded its DuraTALK digital voice processor range with the release of a new low bit-rate 2,4 Kbps vocoder.

Targeted at professional two-way radio, the CMX7262 provides crystal clear voice and excellent performance in real-life radio operation. This is achieved through the use of the latest state-of-the-art voice coding technology called ‘Tri-Wave Excited Linear Prediction’ (TWELP), developed by the digital voice coding experts at DSP Innovations.

The chip handles voice in 20 ms frames, ensuring compatibility with recognised digital PMR standards as well as CML Microcircuits’ range of digital PMR baseband processors.Supporting the voice coding function is a robust forward error correction (FEC) scheme, an important feature to mitigate errors inherent when transmitting over narrowband radio channels in challenging conditions.

Background noise reduction has also been implemented to further enhance voice clarity. Unlike other purely digital-based solutions, the CMX7262 integrates a voiceband audio codec (ADC/DAC functionality), input/output amplifier and loudspeaker driver with digital gain control to give a complete solution of analog voice in to vocoded data out and vocoded data in to analog voice out.

The device operates from a 3,0 V to 3,6 V supply and is supplied in small 64-pin VQFN and LQFP packages.

Further reading:

High-speed PIN diode
Altron Arrow Analogue, Mixed Signal, LSI
Vishay’s new high-speed Silicon PIN diode is able to detect both visible and near infra-red radiation over a wide spectrum range from 350 to 1100 nm.

Read more...

---

Analogue front end for sensor measurements
Electrocomp Analogue, Mixed Signal, LSI
The NJU9103 AFE from Nisshinbo is a tiny analogue front end, with a 16-bit resolution ADC and up to 512 x signal amplification from the programmable gain amplifier.

Read more...

---

Single-channel software configurable I/O
Altron Arrow Analogue, Mixed Signal, LSI
These use cases of the AD74115H include analogue output and input, digital output and input, resistance temperature detector (RTD), and thermocouple measurement capability.

Read more...

---

Current-sense amplifier with PWM rejection
Altron Arrow Analogue, Mixed Signal, LSI
Analog Devices’ AD8410A is a high voltage, high bandwidth current-sense amplifier that features an initial gain of 20 V/V and a 2,2 MHz bandwidth.

Read more...

---

Combining a LPF and ADC driver for a 20 Vp-p signal
Altron Arrow Analogue, Mixed Signal, LSI
A mixed-signal ADC driver circuit’s optimum performance depends on multiple variables: the driver’s settling time, the RC filter’s time constant, driving impedance, and the ADC sampling capacitor’s kickback current, all interact during acquisition time and contribute towards sampling errors.

Read more...

---

Pressure sensor with NextNav certification
EBV Electrolink Analogue, Mixed Signal, LSI
STMicroelectronics’ LPS22DF pressure sensor has received a NextNav certification, which guarantees performance and reliability for geolocation and other types of applications.

Read more...

---

Reference design for Raspberry Pi analogue I/O
Analogue, Mixed Signal, LSI
Analogue Devices has published a reference design for ±10 V analogue input and ±15 V analogue output for Raspberry Pi platforms.

Read more...

---

Multi-zone distance sensor with 90° field of view
Avnet Silica Analogue, Mixed Signal, LSI
STMicroelectronics has revealed a new FlightSense multi-zone distance sensor, with 90° field of view, to bring lifelike situational awareness to applications like home automation, computers, robots, and smart equipment.

Read more...

---

Six-axis IMU with Qvar sensing channel
Altron Arrow Analogue, Mixed Signal, LSI
The LSM6DSV16X from STMicroelectronics is a high-performance, low-power six-axis IMU, featuring a three-axis digital accelerometer and a three-axis digital gyroscope.

Read more...

---

Bidirectional current-sense amplifier with PWM
RS South Africa Analogue, Mixed Signal, LSI
The MAX49925 from Analogue Devices is a bidirectional current-sense amplifier (CSA) with an input common-mode range that extends from -40 to 76 V, making it suitable for 48 V HEV applications where there are large automotive transients.

Read more...

---