TDA9887TSLASHV4 datasheet(10/58 Pages) NXP

No de pièce	TDA9887T/V4

Description	I2C-bus controlled multistandard alignment-free IF-PLL demodulator with FM radio

Download	58 Pages

Scroll/Zoom	100%

Fabricant	NXP [NXP Semiconductors]

Site Internet	http://www.nxp.com

Logo

10 / 58 page

2004 Aug 25

10

Philips Semiconductors

Product speciﬁcation

I2C-bus controlled multistandard alignment-free

IF-PLL demodulator with FM radio

TDA9887

8

FUNCTIONAL DESCRIPTION

Figure 1 shows the simplified block diagram of the device

which comprises the following functional blocks:

• VIF amplifier

• Tuner AGC and VIF-AGC

• VIF-AGC detector

• Frequency Phase-Locked Loop (FPLL) detector

• VCO and divider

• AFC and digital acquisition help

• Video demodulator and amplifier

• Sound carrier trap

• SIF amplifier

• SIF-AGC detector

• Single reference QSS mixer

• AM demodulator

• FM demodulator and acquisition help

• Audio amplifier and mute time constant

• Radio mode

• Internal voltage stabilizer

• I2C-bus transceiver and MAD (module address).

8.1

VIF ampliﬁer

The VIF amplifier consists of three AC-coupled differential

stages. Gain control is performed by emitter degeneration.

The total gain control range is typically 66 dB. The

differential input impedance is typically 2 k

Ω in parallel with

3 pF.

8.2

Tuner AGC and VIF-AGC

This block adapts the voltages, generated at the VIF-AGC

and SIF-AGC detectors, to the internal signal processing

at the VIF and SIF amplifiers and performs the tuner AGC

control current generation. The onset of the tuner AGC

control current generation can be set either via the I2C-bus

(see Table 13) or optionally by a potentiometer at pin TOP

(in case that the I2C-bus information cannot be stored).

The presence of a potentiometer is automatically detected

and the I2C-bus setting is disabled.

Furthermore, derived from the AGC detector voltage, a

comparator is used to test if the corresponding VIF input

voltage is higher than 200

µV. This information can be

read out via the I2C-bus (bit VIFLEV = 1).

8.3

VIF-AGC detector

Gain control is performed by sync level detection (negative

modulation) or peak white detection (positive modulation).

For negative modulation, the sync level voltage is stored at

an integrated capacitor by means of a fast peak detector.

This voltage is compared with a reference voltage

(nominal sync level) by a comparator which charges or

discharges the integrated AGC capacitor for the

generation of the required VIF gain. The time constants for

decreasing or increasing the gain are nearly equal and the

total AGC reaction time is fast to cope with ‘aeroplane

fluttering’.

For positive modulation, the white peak level voltage is

compared with a reference voltage (nominal white level)

by a comparator which charges (fast) or discharges (slow)

the external AGC capacitor directly for the generation of

the required VIF gain. The need of a very long time

constant for VIF gain increase is because the peak white

level may appear only once in a field. In order to reduce

this time constant, an additional level detector increases

the discharging current of the AGC capacitor (fast mode)

in the event of a decreasing VIF amplitude step controlled

by the detected actual black level voltage. The threshold

level for fast mode AGC is typically

−6 dB video amplitude.

The fast mode state is also transferred to the SIF-AGC

detector for speed-up. In case of missing peak white

pulses, the VIF gain increase is limited to typically +3 dB

by comparing the detected actual black level voltage with

a corresponding reference voltage.

8.4

FPLL detector

The VIF amplifier output signal is fed into a frequency

detector and into a phase detector via a limiting amplifier

for removing the video AM.

During acquisition the frequency detector produces a

current proportional to the frequency difference between

the VIF and the VCO signals. After frequency lock-in the

phase detector produces a current proportional to the

phase difference between the VIF and the VCO signals.

The currents from the frequency and phase detectors are

charged into the loop filter which controls the VIF VCO and

locks it to the frequency and phase of the VIF carrier.

For a positive modulated VIF signal, the charging currents

are gated by the composite sync in order to avoid signal

distortion in case of overmodulation. The gating depth is

switchable via the I2C-bus.

Numéro de pièce similaire - TDA9887T/V4

Fabricant	No de pièce	Fiches technique	Description
NXP Semiconductors	TDA9887T/V4	308Kb / 58P	I2C-bus controlled multistandard alignment-free IF-PLL demodulator with FM radio 2004 Aug 25

More results

Description similaire - TDA9887T/V4

Fabricant	No de pièce	Fiches technique	Description
NXP Semiconductors	TDA9887	308Kb / 58P	I2C-bus controlled multistandard alignment-free IF-PLL demodulator with FM radio 2004 Aug 25
	TDA9880	195Kb / 40P	Alignment-free multistandard vision and FM sound IF-PLL demodulator 1999 Jul 21
	TDA9885	248Kb / 56P	I2C-bus controlled single and multistandard alignment-free IF-PLL demodulators 2003 Oct 02
	TDA9886	283Kb / 56P	I2C-bus controlled single and multistandard alignment-free IF-PLL demodulators Rev. 03-16 December 2008
	TDA9884	301Kb / 58P	I2C-bus controlled multistandard alignment-free IF-PLL for mobile reception Rev. 02-12 May 2006
	TDA9884TS	231Kb / 55P	I2C-bus controlled multistandard alignment-free IF-PLL for mobile reception 2003 Nov 28
	TDA9882	236Kb / 45P	Alignment-free multistandard vision and QSS FM sound IF PLL demodulator Rev. 01-16 November 2004
	TDA9816M	286Kb / 44P	Multistandard multimedia IF-PLL and FM radio demodulator 1997 Nov 19
	TDA9814T	249Kb / 36P	Multistandard VIF-PLL with QSS-IF and dual FM-PLL/AM demodulator 1998 Feb 09
	TDA9806	193Kb / 24P	Multistandard VIF-PLL and FM-PLL demodulator 1995 Sep 05

More results

TDA9887T/V4 Fiches technique(PDF) 10 Page - NXP Semiconductors

TDA9887T/V4 Fiches technique(HTML) 10 Page - NXP Semiconductors

Numéro de pièce similaire - TDA9887T/V4

Description similaire - TDA9887T/V4

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58

Fiches technique Télécharger

Lien URL