RCA ATC311 free download

File name RCA Chassis ATC311 (Service Manual).pdf

ATC311 CIRCUIT OVERVIEW ATC311 CIRCUIT OVERVIEW · 60 watts total audio (15W X2 front speakers, 30W integrated subwoofer). · Center channel input · 8 sensor autoconvergence · Gemstar EPG · All models with integrated frame comb The deflection supply provides the majority of the run supplies which are switched On/Off by the I2C data bus from the DM2 module. A three-terminal error amplifier IC senses the 12 volt supply and provides feedback to the control circuit through an optoisolator. A power-fail signal is provided to the DM2 module to provide advance warning of an imminent supply voltage dropout. CHASSIS DESCRIPTION The ATC311 is the replacement for the DTV307 it includes: · Enhanced features over the DTV307 · Entirely new chassis platform + new DM2 · 16X9 only (40", 52", 61" and 65" sizes) ACIN/Digital Power Supply Functional Description The ACIN /Digital power supply used for the ATC311 is a flyback-type, current-mode controlled, zero voltage switching (ZVS) topology utilizing a discrete control circuit and cold-side regulation. The circuit is functionally similar to those used for DVD, MMDS2, and other digital box applications. Block Diagram - 5VS Raw B+ 33VS 6VS Drive SMT +21V - 21V 12VS +5VR 5VS Power Fail Circuit Operation The principle of this power supply is a flyback type zero voltage switching (ZVS) converter operating in the discontinuous mode. A start-up resistor , R24604, provides the initial gate bias voltage for the MOSFET, Q24601, which begins to conduct. A positive feed back winding (8-7) on the transformer T24601 begins to increase the gate voltage and causes Q24601 to eventually saturate and begin the first cycle of operation. As the current in Q24601 increases, the voltage drop across the current sense resistor, R24601 increases until a threshold level is reached. At this point the transistor Q24602 turns on and the gate drive of the MOSFET is removed. The current flowing in Q24601 drops quickly to zero and the energy stored in the primary inductance of the transformer is transferred to the resonating capacitor, C24609, causing the voltage across the capacitor to rise. The rising voltage appears across the secondary windings (15-16) and causes a rectifier diode, CR24612, to conduct when the voltage exceeds the voltage across the filter capacitor , C24624. When CR24612 conducts the energy stored in the primary inductance of the transformer is delivered to the output ACIN/Digital Power Supply Key Features of the ATC311 · NTSC and 1H inputs displayed at 2H · Integrated ATSC receiver (terrestrial only ­ no DSS) · Analog on analog Picture-In-Picture capability (GPIP) w/ twin tuners · Two RF inputs · 2 sets composite inputs w/ S-video · 1 set front composite inputs w/ S-video and headphone jack output · 2 multisync component inputs + composite inputs · 1 Digital Video Interface (DVI) input · IEEE 1394 "Firewire" interface · Ethernet connector with integrated Web Browser · SD Video output from HD source ATC311 Power Supply Sys