TDA7540B STMicroelectronics, TDA7540B Datasheet - Page 38

• Manufacturer Part Number: TDA7540B
• Manufacturer: STMicroelectronics

Specifications of TDA7540B

• Case: TQFP
• Dc: 06+
• Lead Free Status / Rohs Status: Compliant

DOCUMENT CD00108485
Copyright STMicroelectronics
Functional description
4.5
4.5.1
4.5.2
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REVISION 1.0
This is detected by a control logic and an external search stop output is changing from LOW
to HIGH. The frequency range inside which a successful count result is adjustable by the
EW bits.
The IF counter is only started by inlock information from the PLL part. It is enabled by
software (IFENA).
Adjustment of the measurement sequence time
The precision of the measurements is adjustable by controlling the discrimination window.
This is adjustable by programming the control registers EW.
The measurement time per cycle is adjustable by setting the registers IFS.
Adjust of the Frequency Value
The center frequency of the discrimination window is adjustable by the control registers CF.
I
The TDA7540 supports the I
data onto the bus as a transmitter, and the receiving device as the receiver. The device that
controls the transfer is a master and device being controlled is the slave. The master will
always initiate data transfer and provide the clock to transmit or receive operations.
Data transition
Data transition on the SDA line must only occur when the clock SCL is LOW. SDA transitions
while SCL is HIGH will be interpreted as START or STOP condition.
Start condition
A start condition is defined by a HIGH to LOW transition of the SDA line while SCL is at a
stable HIGH level. This "START" condition must precede any command and initiate a data
transfer onto the bus. The device continuously monitors the SDA and SCL lines for a valid
START and will not response to any command if this condition has not been met.
2
C-Bus interface
t
t
t
Counter result succeeded:
t
t
Counter result failed:
t
t
t
t
t
CNT
CNT
CNT
TIM
TIM
TIM
TIM
TIM
CNT
ERR
≥
≤
> t
< t
= IF timer cycle time (sampling time)
= (CF + 1696+1) / f
= (CF + 10688+1) / f
= (CF + 488+1) / f
= IF counter cycle time
= discrimination window (controlled by the EW registers)
t
t
CNT
CNT
CNT
CNT
- t
+ t
+ t
- t
ERR
ERR
ERR
ERR
IF
2
IF
C-Bus protocol. This protocol defines any device that sends
IF
COMPANY INTERNAL
FM mode
AM up conversion mode
AM mode
ACTIVE
Unauthorized reproduction and communication strictly prohibited
DATE 11-May-2006
TDA7540B
page: 34/75