FM1246

TUNERS DATA SHEET FM1246 Desktop video & FM radio module system CCIR I Preliminary specification File under Tuners, DC03 1997 May 14 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I FEATURES • System I and FM radio broadcast • True 5 V device (low power dissipation) • Full TV frequency range from channel A (45.75 MHz) to channel 69 (855.25 MHz) • FM radio band coverage from 87.50 to 108.00 MHz • PLL controlled tuning • Programmable PLL step size (31.25, 50 or 62.5 kHz) • True-synchronous vision IF demodulator (PLL) • Ultra-linear FM PLL demodulator for FM radio broadcast • Demodulated video output, AF sound output, second sound IF output • I2C-bus control of tuning, address selection, AFC status information • Complies with European regulations on radiation, signal handling and immunity “CENELEC 55020, 55013’’ • Small horizontally mounted metal housing. DESCRIPTION The FM1246 front-end is designed to receive both TV and FM stereo signals in the PC Multimedia environment. The units are available with separate 75 Ω inputs for TV and FM broadcast reception. The input connectors available are either standard phono or IEC type (female for TV, male for FM radio). The tuning, bandswitching and antenna selection are made through the I2C-bus. The front-end covers the TV bands from 45.75 MHz to 855.25 MHz. The FM band covers the standard 87.50 MHz to 108.00 MHz. An RDS decoder can be connected to the AF-MPX output. The FM1246 meets the input immunity and radiation requirements of CENELEC. The FM1246 consists of a TV tuner, an FM radio tuner and an IF section, all on a single PCB. The front-end is assembled in a metal housing made of a rectangular tin-plated steel frame, with front and rear covers, which have soldered contacts to the frame. The two phono or IEC antenna connectors (female for TV, male for FM radio) are mounted on one side of the frame for the TV/FM signal inputs. All other connections are made via pins at the bottom. The TV IF section uses an intercarrier SAW filter, followed by a true-synchronous vision IF demodulator (PLL) IC. The analog AFC voltage is fed to the 5-level A/D converter in the PLL tuning IC, so that the AFC status can be read via the I2C-bus. FM1246 In the FM radio mode, the level detector and AFT functions are provide for the auto-search routines. The level detector and AFT status can be read from the A/D bits in the status-byte. The mute function is also provided to suppress the audio output signal, if required. The tuner AGC for both TV and FM radio operation, is generated with a novel AGC detector which measures the IF signal level directly at the tuner IF output pins. As opposed to the conventional AGC detector, this new circuit allows a higher take-over level and offers superior immunity against tuner overload. The demodulation of the TV sound and FM radio IF (10.70 MHz) is done with a PLL demodulation circuit contained in the IF IC. In the FM radio mode, the multiplexed AF signal is then channelled to a stereo decoder IC which extracts the left/right analog signals. The multiplexed audio signal is also available at pin 25 to support RDS implementations. The 2nd IF TV sound output is provided to connect external (analog 2 carrier or digital) stereo processing. ORDERING INFORMATION TYPE FM1246/HM/PH FM1246/HM/I MARKING The following items of information are printed on a sticker that is on the top cover of the tuner: • Type number • Code number • Origin letter of factory • Change code • Year and week code. DESCRIPTION standard phono IEC connector CATALOGUE NUMBERS 3139 147 13901 3139 147 13911 1997 May 14 2 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I INTERMEDIATE FREQUENCIES SYSTEM Picture carrier Colour Sound NICAM FM PINNING SYMBOL VT VS(tuner) SCL SDA AS AF O/P right AF O/P left 2nd IF O/P CVBS VS(IF) AF O/P − PIN 11 12 13 14 15 20 21 22 23 24 25 TH1, TH2, TH3 and TH4 DESCRIPTION tuning voltage (monitor) supply voltage tuner section +5 V I2C-bus serial clock I2C-bus serial data I2C-bus address select FM radio right channel FM radio left channel second IF TV sound output FREQUENCY (MHz) 38.90 34.47 32.90 32.348 10.70 CHANNEL COVERAGE BAND FM radio band Low band Mid band High band FM1246 FREQUENCY (MHz) 87.50 to 108.00 45.75 to 170.00 170.00 to 450.00 450.00 to 855.25 Composite Video Baseband Signal (CVBS) output supply voltage IF section +5 V AF sound output mounting tags (ground) 1997 May 14 3 handbook, full pagewidth 1997 May 14 10.7 MHz FILTER MIXER - OSCILLATOR IC IF AGC DETECTOR 2nd IF FILTER HIGH OSC. SAW VIF MID OSC. VIF PLL DEMODULATOR BLOCK DIAGRAM Philips Components TV antenna HIGH BAND MID BAND FM antenna Desktop video & FM radio module system CCIR I VCO LOW OSC. TRAP FM-IF FM DEMODULATOR 4 10.7 MHz FILTER AFT PLL 11 VT +5 V SCL SDA AS monitor VS( tuner) 12 13 14 15 20 21 LOW BAND DISCRIMINATOR 10.7 MHz VT STEREO DECODER DC-DC CCA505 22 AF-R AF-L 2nd IF sound output 23 24 25 CVBS +5 V AF VS(IF) (TV) Preliminary specification FM1246 Fig.1 Electrical block diagram. Philips Components Preliminary specification Desktop video & FM radio module system CCIR I LIMITING VALUES Limiting values under operational conditions The tuner can be guaranteed to function properly under the following conditions. SYMBOL VS VS(ripple) supply voltage peak-to-peak ripple voltage susceptibility (at 5 V ±5%); note 1 20 Hz to 100 kHz >100 kHz to 500 kHz IS(tuner) VSCL VSDA ISDA VAS VAFright(FM) ZAFright(FM) supply current SCL bus input voltage SDA bus input voltage SDA bus current (open collector) address select voltage; note 2 FM right channel DC voltage FM right channel load impedance parallel connected: resistive value capacitive value VAFleft(FM) ZAFleft(FM) FM left channel DC voltage FM left channel load impedance: resistive value capacitive value ZIF ZCVBS tL VS(IF) IS(IF) ZAF 2nd IF sound output load impedance 22 23 24 Composite Video Baseband Signal load impedance CVBS load time constant IF supply voltage IF supply current AF sound output load impedance parallel connected: resistive value capacitive value Notes 25 5.0 − − − − 4 21 20 13 14 15 PARAMETER PIN MIN. 4.75 TYP. 5.00 FM1246 MAX. 5.25 UNIT V 12 − − − −0.3 −0.3 −1 − − − − − − − 0.5 − − 4.75 − − − − − − − − 1.0 50 9 1.0 50 9 − 75 − 5.0 − 5 10 120 +5.25 +5.25 +5 +5.25 − − − − − − − − 100 5.25 150 mV mV mA V V mA V V kΩ pF V kΩ pF kΩ Ω ns V mA kΩ nF 1. Sinusoidal ripple voltage superimposed on the 5 V supply voltage in the frequency range of 20 Hz to 500 kHz. Criteria for TV interference >57 dB. 2. For detailed information about the address decoding, refer to Chapter “Application information”. 1997 May 14 5 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I Environmental conditions SYMBOL PARAMETER CONDITIONS MIN. −25 − 25 g 50 g 10 to 55 Hz − − − −10 − − − − − 0.35 − − TYP. MAX. FM1246 UNIT °C % m/s2 m/s2 mm °C % Non-operational conditions Tamb RH gB gS ambient temperature relative humidity bump acceleration shock acceleration vibration amplitude Operational conditions Tamb RH ambient temperature relative humidity +60 95 +85 100 245 490 − OVERALL PERFORMANCE Conditional data Unless otherwise specified, all electrical values for Chapter “Overall performance” apply at the following conditions. SYMBOL Tamb RH VS ZCVBS ZIF ZAF tpr ZS(AE) ambient temperature relative humidity supply voltage (tuner and IF section) video output load impedance (DC) 2nd IF sound output load impedance (DC) AF sound output load impedance pre-heating time (+5 V at pin 24) aerial source impedance (asymmetrical) PARAMETER VALUE 25 ±5 60 ±15 5 ±0.125 75 0.5 100 10 75 °C % V Ω kΩ kΩ minutes Ω UNIT 1997 May 14 6 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I TUNER CHARACTERISTICS For detailed information about the PLL programming, refer to Chapter “Application information”. FM1246 The desktop video tuner is guaranteed to function properly within the specified operational conditions, but a certain deterioration of performance parameters may occur at the limits of the operational conditions. Required data for test equipment to be used EQUIPMENT DC voltmeter Oscilloscope input impedance input impedance: resistance capacitance Spectrum analyzer FET probe input impedance input impedance: resistance capacitance output impedance voltage gain AC millivoltmeter input impedance 1 3.5 50 0 >100 MΩ pF Ω dB kΩ >1 1 VALUE MΩ UNIT 1997 May 14 7 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I FM1246 handbook, full pagewidth aerial connector TP2 9 10 11 12 13 14 15 TP3 20 21 22 23 24 25 IF output IF PROBE OUT 5V VT BU2 VS SCL SDA 39 kΩ 39 kΩ 220 nF 220 nF + 47 µF 22 Ω 1 nF 3 kΩ 33 µF 47 kΩ 1/ 2 TDA1308 240 kΩ 6 − 4 7 5 + 240 kΩ 2 − 1 3 + 8 1/ 2 + 10 nF 1 µF 47 kΩ TDA1308 + 47 µF 22 Ω + 47 µF 22 Ω 220 kΩ 220 kΩ BU7 BU8 BU5 BU4 video out BU2 +5 V 5 kΩ (2) (1) TEST JIG CCA650 BU6 P S1 15 kHz LOW-PASS FILTER DA (1) BU4 loaded with 75 Ω. (2) 50 µs de-emphasis. SA = Spectrum Analyzer. P = FET probe. DA = Distortion Analyzer. VAC = dual channel AC voltmeter (Zi = 600 Ω). The minimum load impedance required at the CVBS output (pin 23) is 75 Ω (both AC and DC). SA 10 nF DA Fig.2 Typical test set up. 1997 May 14 8 Philips Components Preliminary specification Desktop video & FM radio module system CCIR I Definitions of test signals (see Fig.2) TEST SIGNAL A0: unmodulated vision carrier A1: CCIR I standard signal with video modulation B1: unmodulated sound carrier I system B2: FM modulated sound carrier I system B3: unmodulated sound carrier I system C1: FM modulated sound carrier C2: FM modulated sound carrier C3: FM modulated sound carrier C4: FM modulated sound carrier C5: unmodulated sound carrier Aerial input characteristics SYMBOL VSWR PARAMETER reflection coefficient CONDITIONS referred to 75 Ω impedance (worst case on or between picture and sound carrier at maximum gain): all channels in TV mode FM (centre of channel) VPSM Vant surge protection voltage antenna connection disturbance voltage