SAB6456, Elektronika, elementy
[ Pobierz całość w formacie PDF ]
INTEGRATED CIRCUITS DATA SHEET SAB6456 SAB6456T Sensitive 1 GHz divide-by-64/divide-by-256 switchable prescaler Product specification File under Integrated Circuits, IC02 June 1986 Philips Semiconductors Product specification Sensitive 1 GHz divide-by-64/divide-by-256 switchable prescaler SAB6456 SAB6456T GENERAL DESCRIPTION The SAB6456/SAB6456T is a prescaler for UHF/VHF tuners. It can be switched to divide-by-64 or divide-by-256 by the mode-control (MC) pin. The circuit has an input frequency range of 70 MHz to 1 GHz, has high input sensitivity and good harmonic suppression. Fig.1 Block diagram. QUICK REFERENCE DATA PARAMETER CONDITIONS SYMBOL MIN. TYP. MAX. UNIT Supply voltage pin 8 to pin 4 V CC 4,5 5,0 5,5 V Supply current pin 8 I CC - 21 - mA Input frequency range pins 2 and 3 f i 70 - 1000 MHz Sensitivity to input voltage (r.m.s. value) V i(rms) - - 10 mV Output voltage (peak-to-peak value) pins 6 and 7 V o(p-p) - 1 - V Operating ambient temperature range T amb 0 - 80 ° C PACKAGE OUTLINES SAB6456 : 8-lead DIL; plastic (SOT97); SOT97-1; 1996 November 18. SAB6456T: 8-lead mini-pack (SO8; SOT96A); SOT96-1; 1996 November 18. June 1986 2 Philips Semiconductors Product specification Sensitive 1 GHz divide-by-64/divide-by-256 switchable prescaler SAB6456 SAB6456T PINNING 1. n.c. not connected 2. C1 differential inputs 3. C2 4. V EE ground (0 V) 5. MC mode control 6. Q H complementary outputs 7. Q L 8. V CC positive supply voltage Fig.2 Pinning diagram. FUNCTIONAL DESCRIPTION The circuit comprises an input amplifier, a divider stage with selectable division ratio and an output stage. The input amplifier is driven by a sinusoidal signal from the local oscillator of a television tuner. The inputs (C1, C2) are differential and are biased internally to permit capacitive coupling. When driven asymmetrically the unused input should be connected to ground via a capacitor. The mode-control (MC) input to the divider stage is intended for static control of the division ratio, selection is made as follows: divide-by-64: MC pin open-circuit divide-by-256: MC pin connected to ground The divider stage may oscillate during no-signal conditions but this oscillation is suppressed when input signals are received. Two complementary signals (Q H , Q L ) are provided by the output differential amplifier stage. The voltage-edges of the output signals are slowed internally to reduce harmonics in the television intermediate frequency band. June 1986 3 Philips Semiconductors Product specification Sensitive 1 GHz divide-by-64/divide-by-256 switchable prescaler SAB6456 SAB6456T ELECTROSTATIC DISCHARGE PROTECTION Inputs and outputs have electrostatic discharge protection according to specification MIL-883C, class B. RATINGS Limiting values in accordance with the Absolute Maximum System (IEC-134) PARAMETER CONDITIONS SYMBOL MIN. TYP. MAX. UNIT Supply voltage pin 8 to pin 4 V CC - - 7,0 V Input voltage V i - - V CC V Storage temperature range T stg - 55 - + 150 ° C Junction temperature T j - - + 150 ° C THERMAL RESISTANCE From junction to ambient 8-lead DIL; plastic (SOT-97A) R th j-a 120 K/W 8-lead mini-pack (SO-8; SOT-96A) on printed circuit board R th j-a 260 K/W on ceramic substrate R th j-a 170 K/W C; test IC mounted in a test socket or on a printed circuit board; measurements taken after thermal equilibrium is established ° PARAMETER CONDITIONS SYMBOL MIN. TYP. MAX. UNIT Output voltage HIGH V OH - - V CC V Output voltage LOW V OL - - V CC - 0.8 V Supply current I CC - 21 28 mA Mode-control (MC) Input voltage LOW (divide-by-256) V IL 0 - 0,2 V Input current LOW - I L - 25 60 m A Input voltage HIGH (divide-by-64) pin 5 open-circuit V IH 1,4 - 3,0 V June 1986 4 D.C. CHARACTERISTICS V CC =5V; V EE =0V; T amb =25 Philips Semiconductors Product specification Sensitive 1 GHz divide-by-64/divide-by-256 switchable prescaler SAB6456 SAB6456T A.C. CHARACTERISTICS V CC = 4,5 to 5,5 V; V EE =0V; T amb = 0 to + 80 ° C PARAMETER CONDITIONS SYMBOL MIN. TYP. MAX. UNIT Sensitivity to input 50 W system voltage (r.m.s. value) f i = 70 MHz V i(rms) - - 10 mV f i = 150 MHz V i(rms) - - 10 mV f i = 300 MHz V i(rms) - - 10 mV f i = 500 MHz V i(rms) - - 10 mV f i = 900 MHz V i(rms) - - 10 mV f i = 1000 MHz V i(rms) - - 10 mV Input overload voltage 50 W system (r.m.s. value) f i = 70 MHz to 1000 MHz V i 300 - - mV Input parallel resistance f i = 70 MHz R i - 560 - W f i = 1000 MHz R i - 30 - W Input capacitance f i = 70 MHz C i - 5 - pF f i = 1000 MHz C i - 1,5 - pF Output voltage HIGH V OH - - V CC V Output voltage LOW V OL - - V CC - 0,8 V Output voltage swing (peak-to-peak value) f i = 70 MHz V o(p-p) 0,8 1,0 1,2 V f i = 1000 MHz; R L = 820 W V o(p-p) 0,17 - - V Attenuation of third harmonic at output f i = 800 MHz; R L = 820 ; C L =60pF W - 15 - 23 - dB Output unbalance see Fig.3 D V o - - 0,1 V Output resistance R o - 500 - W June 1986 5 ; C L =60pF [ Pobierz całość w formacie PDF ] |