Electronic Components Datasheet Search |
|
MSP34X2G Datasheet(PDF) 96 Page - Micronas |
|
MSP34X2G Datasheet(HTML) 96 Page - Micronas |
96 / 104 page MSP 34x2G PRELIMINARY DATA SHEET 96 Micronas 6.4.4. NICAM Error Rate Register Average error rate of the NICAM reception in a time interval of 182 ms, which should be close to 0. The ini- tial and maximum value of ERROR_RATE is 2047. This value is also active if the NICAM bit of MODE_REG is not set. Since the value is achieved by filtering, a certain transition time (approx. 0.5 sec) is unavoidable. Acceptable audio may have error rates up to a value of 700 int. Individual evaluation of this value by the controller and an appropriate threshold may define the fallback mode from NICAM to FM/ AM-Mono in case of poor NICAM reception. The bit error rate per second (BER) can be calculated by means of the following formula: BER = ERROR_RATE * 12.3*10−6 /s 6.4.5. PLL_CAPS Readback Register It is possible to read out the actual setting of the PLL_CAPS. In standard applications, this register is not of interest for the customer. 6.4.6. AGC_GAIN Readback Register It is possible to read out the actual setting of AGC_GAIN in Automatic Gain Mode. In standard applications, this register is not of interest for the cus- tomer. 6.4.7. Automatic Search Function for FM-Carrier Detection in Satellite Mode The AM demodulation ability of the MSP 34x2G offers the possibility to calculate the “field strength” of the momentarily selected FM carrier, which can be read out by the controller. In SAT receivers, this feature can be used to make automatic FM carrier search possible. For this, the MSP has to be switched to AM-mode (MODE_REG[8]), FM-Prescale must be set to 7Fhex = +127dec, and the FM DC notch (see section 6.5.7.) must be switched off. The sound-IF frequency range must now be “scanned” in the MSP-channel 2 by means of the programmable quadrature mixer with an appropriate incremental frequency (i.e. 10 kHz). After each incrementation, a field strength value is available at the quasi-peak detector output (quasi-peak detector source must be set to FM), which must be examined for relative maxima by the controller. This results in either continuing search or switching the MSP back to FM demodulation mode. During the search process, the FIR2 must be loaded with the coefficient set “AUTOSEARCH”, which enables small bandwidth, resulting in appropriate field strength characteristics. The absolute field strength value (can be read out of “quasi-peak detector output FM1”) also gives information on whether a main FM carrier or a subcarrier was detected; and as a practical consequence, the FM bandwidth (FIR1/2) and the deemphasis (50 µs or adaptive) can be switched accordingly. Due to the fact that a constant demodulation frequency offset of a few kHz leads to a DC level in the demodu- lated signal, further fine tuning of the found carrier can be achieved by evaluating the “DC Level Readout FM1”. Therefore, the FM DC Notch must be switched on, and the demodulator part must be switched back to FM-demodulation mode. For a detailed description of the automatic search function, please refer to the corresponding MSP Win- dows software. ERROR_RATE 00 57hex Error free 0000hex maximum error rate 07FFhex PLL_CAPS 02 1Fhex L minimum frequency 1111 1111 FFhex nominal frequency 0101 0110 56hex RESET maximum frequency 0000 0000 00hex PLL_CAPS 02 1Fhex H PLL open xxxx xxx0 PLL closed xxxx xxx1 AGC_GAIN 02 1Ehex max. amplification (20 dB) 0001 0100 14hex min. amplification (3 dB) 0000 0000 00hex |
Similar Part No. - MSP34X2G |
|
Similar Description - MSP34X2G |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |