tea5761uk NXP Semiconductors, tea5761uk Datasheet - Page 12

• Manufacturer Part Number: tea5761uk
• Description: Tea5761uk Low-voltage Single Chip Fm-stereo Radio
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 13451
Product data sheet
8.20.3 Auto high-side and low-side injection stop switch
When a channel is searched or a preset is done, reception can sometimes be improved
when Local Oscillator (LO) injection is done at the other side of the wanted channel.
Bit HLSI toggles the injection of the local oscillator from high-side (bit HLSI = 1) to
low-side (bit HLSI = 0). When bit HLSI is toggled, a new PLL setting must be sent to the
TEA5761UK.
Fig 3. Flowchart auto search or preset
unless bit AFM is set or bit AHLSI is set
during a preset mute is always active
search mode is default not muted
wait for PLL to settle
set PLL frequency
FRRFLAG = 1
BLFLAG = 0
reset flags
level OK
no mute
IF OK
start
true
true
Rev. 01 — 2 August 2006
false
false
FRRFLAG = 1
BLFLAG = 0
AHLSI
mute
set LEVFLAG
true
false
false
increment current_pll
Low voltage single-chip FM stereo radio
search mode
by 100 kHz
search up
true
true
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
FRRFLAG = 1
BLFLAG = 1
band limit
no mute
false
TEA5761UK
true
decrement current_pll
by 100 kHz
false
001aab461
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