TEF6862HL/V1/S422: NXP Semiconductors, TEF6862HL/V1/S422: Datasheet - Page 9

• Manufacturer Part Number: TEF6862HL/V1/S422:
• Manufacturer: NXP Semiconductors

Specifications of TEF6862HL/V1/S422:

• Lead Free Status / Rohs Status: Compliant

Philips Semiconductors
TEF6862_1
Product data sheet
7.12 Crystal oscillator
7.13 Tuning PLL
7.14 Antenna DAA
7.15 AM RF AGC
7.16 AM mixer
7.17 AM IF noise blanker
These dividers generate in-phase and quadrature-phase output signals used in the
FM front-end mixer for image rejection. In AM mode the LO frequency is divided by 6, 8,
10, 16 or 20 depending on the selected AM band.
The linear crystal oscillator provides a 20.5 MHz signal. A divider-by-two generates
in-phase and quadrature-phase mixer frequencies for the conversion from IF1 to IF2
including image rejection. The reference divider generates from the crystal frequency
various reference frequencies for the tuning PLL. Also the different timing signals for the
sequential machine as well as the analog signal processor reference frequency are
derived from the crystal reference.
The tuning PLL locks the VCO frequency divided by the programmable divider ratio to the
reference frequency. Due to the combination of different charge pump signals in the
PLL loop filter, the loop parameters are adapted dynamically. Tuning to different radio
frequencies is done by changing the programmable divider ratio. The tuning step size is
selected with the reference frequency divider setting.
The antenna DAA measures the VCO tuning voltage and multiplies it with a factor defined
by the 7-bit DAA1 setting to generate a tuning voltage for the FM antenna tank circuit.
A second tuning voltage (DAA output 2) for an optional second FM tank circuit is derived
from the first tuning voltage with 4 bits.
The AM front-end is designed for the application of an external JFET low noise amplifier
with cascode AGC and PIN diode AGC both controlled by an integrated AGC circuit. Four
AGC thresholds of the detector at the first mixer input are selectable via I
detector at the IF AGC input prevents undesired overload (see
information can be read out via I
pull-up current source for reverse biasing of the PIN diode, when the AGC is not active to
achieve a low parasitic capacitance.
The large dynamic range AM mixer converts AM RF (144 kHz to 26.1 MHz) to an IF of
10.7 MHz.
The spike detection for the AM noise blanker is at the output of the AM front-end mixer.
Blanking is realized at the output of the second AM mixer. The sensitivity of the noise
blanker can be set in three settings and switched off via I
Rev. 01 — 14 September 2006
2
C-bus. The PIN diode current drive circuit includes a
Car Radio Enhanced Selectivity Tuner (CREST)
2
C-bus.
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
Figure
21). AGC
TEF6862
2
C-bus. A further
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