PLL SAA1057

[alsell]

Olá:
Estou tentando utilizar o PLL SAA1057, porém lendo o datasheet do componente não consegui entender muito sobre a comunicação.
Alguém já utilizou e dominou o protocolo?
O que são aqueles bits de controle de amplificação (CP0...CP3)? E os dados a serem transmitidos a seguir? Afinal a frequência que sejo, divido por 32KHz?
Obrigado.

[Djalma Toledo Rodrigues]

Esse componente é para Sintonizador AM FM

Recebe amostra do Sinal do Oscilador AM ou Oscilador FM e controla o Varicap do Oscilador para a freq. requerida.

A Frequência desejada vem da Serial Dlen = E ou CS Clb = Clock e Data

CP0 ... CP3 é a programação de Ganho do Amplificador de Corrente Saida pelo Pino 6


É esta mesma a finalidade que pretende ?
.

[alsell]

Sim, seria praticamente isto, quero utilizá-lo num VCO para um receptor de rádio AM/CW com Dupla Conversão.
E o Data Word A e Data Word B, qual levo em consideração?
Obrigado.

[Djalma Toledo Rodrigues]

Esta no Datasheet

APPLICATION INFORMATION
Initialize procedure
Either a train of at least 10 clock pulses should be applied to the clock input (CLB) or
word B should be transmitted, to achieve proper initialization of the device.
For the complete initialization (defining all control bits) a transmission of word B should
follow. This means that the IC is ready to accept word A.
Synchronous/asynchronous operation
Synchronous loading of the frequency word into the programmable counter can be
achieved when bit ‘SLA’ of word B is set to ‘1’. This mode should be used for small frequency
steps where low tuning noise is important (e.g. search and
manual tuning).
This mode should not be used for frequency changes of more than 31 tuning steps.
In this case asynchronous loading is necessary. This is achieved by setting bit ‘SLA’ to ‘0’.
The in-lock condition will then be reached more quickly, because the frequency
information is loaded immediately into the divider.

APPLICATION INFORMATION
Initialize procedure
Either a train of at least 10 clock pulses should be applied to the clock input (CLB)
or word B should be transmitted, to achieve proper
initialization of the device.
For the complete initialization (defining all control bits) a transmission of word B should
follow. This means that the IC is
ready to accept word A.

Synchronous/asynchronous operation
Synchronous loading of the frequency word into the programmable counter can
be achieved when bit ‘SLA’ of word B is set to ‘1’. This mode should be used for small
frequency steps where low tuning noise is important (e.g. search and
manual tuning).
This mode should not be used for frequency changes of more than 31 tuning steps.
In this case asynchronous loading is necessary. This is achieved by setting bit ‘SLA’
to ‘0’. The in-lock condition will then be reached
more quickly, because the frequency information is loaded immediately into the divider.

Ver Fig. 3
.