TDA7540NTR STMicroelectronics, TDA7540NTR Datasheet - Page 31

• Manufacturer Part Number: TDA7540NTR
• Description: IC TUNER AM/FM CAR RADIO 80-LQFP
• Manufacturer: STMicroelectronics

Specifications of TDA7540NTR

• Frequency: 10.7MHz
• Modulation Or Protocol: AM, FM
• Applications: Automotive Audio
• Current - Receiving: 12mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 7.7 V ~ 9 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Sensitivity: -
• Memory Size: -
• Data Rate - Maximum: -
• Lead Free Status / Rohs Status: Compliant

TDA7540N
Stereoblend control
The stereoblend control block converts the internal LEVEL-voltage into a demodulator
compatible analog signal, which is used to control the channel separation between 0dB and
the maximum separation. Internally this control range has a fixed upper limit, which is the
internal reference voltage
V
To adjust the external LEVEL-voltage to the internal range two values must be defined: the
LEVEL gain L
reached (VST) the LEVEL gain L
estimate the gain:
The MONO-voltage VMO (0dB channel separation) can be chosen selecting VSBL.
Figure 6.
The stereo blend function can be switched ON/OFF using bit Addr25<d2>. Please note that
in AM it must be switched in forced mono!
Highcut control
The highcut control set-up is similar to the stereoblend control set-up: the starting point
VHCH can be set with 2 bits to be 42, 50, 58 or 66% of V
to be 11, 18.3, 25.7 or 33% of VHCH (see
Figure 7.
REF1
in 4% steps (see
Relation between internal and external level-voltagees and setup of
stereoblend
Highcut characteristics
G
and VSBL. To adjust the voltage where the full channel separation is
Figure
Lowpass
time constant
3 • Deemp
τ Deemp
V
REF1
6).
. The lower limit can be programmed between 29 and 58% of
L
G
G
= V
has to be defined. The following equation can be used to
VHCL
REF1
Figure
/FSU@full stereo
7).
VHC H
REF1
whereas the range can be set
Fieldstrength
Functional description
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