Preface
This power board model is APDP-209A2, the power board is single-sided, the power devices are equipped with heat sinks, and the pins corresponding to high-current components are also equipped with rivets to increase the force area and improve reliability. The power board is a PFC+LLC architecture with a boost driver for the LED backlight and a standby power supply. The following charging head network will bring the dismantling of Delta's power board to understand the materials used in the TV power board.
Exterior of the power strip of a Sony LCD TV
The front space of the power board of Sony LCD TV is rich, the layout of each device is relatively sparse, and the power device is equipped with a heat sink.
The soldering on the back of the PCB board is clean and neat, and the workmanship level is excellent.
The measured length of the PCB board is about 29cm.
The width is 24.5cm.
The maximum thickness is 14.7mm.
In addition, the weight of the power strip was measured to be about 585g.
Sony LCD TV power strip disassembly
The power board input fuse specification is 5A 250V.
TVR10621 varistors are used to absorb overvoltage surges.
The common mode inductor is magnetically surrounded, and the bottom is insulated with a bakelite board.
The safety X2 capacitor is from Okaya and has a specification of 0.33μF.
The two common mode inductors are wound with a magnetic core, the core is insulated with a plastic shell, and the middle one has a safety X2 capacitor with a specification of 0.22μF.
The blue Y capacitor is from Murata.
The rectifier bridge is fixed to the heat sink using screws.
The rectifier bridge comes from the new electric element and is specified at 4A 800V.
TVR10621 varistors are used to absorb overvoltage surges.
Two SCK 057 NTC thermistors are connected in series to suppress inrush currents at power-up.
The three thin-film filter capacitors are from TDK and are rated at 1μF 450V.
Close-up of magnetic ring filter inductor.
Two diodes are connected in series for PFC circuit bypass.
The PFC controller is from onsemi, model NCP1612, adopts critical conduction operation mode, and adopts the current control frequency foldback method to improve the conversion efficiency. The chip adopts valley switch, has perfect protection function, has PFCOK signal output, and adopts SOIC-10 package.
The heat sink is provided with a PFC switch tube and a PFC rectifier tube.
其中PFC开关管来自东芝，型号TK15A60U，NMOS，耐压600V，导阻240mΩ。
A 56mΩ resistor is used to sense the PFC switch current.
PFC boost inductors are wound with litz wire.
The PFC rectifier from STMicroelectronics, model number STTH8R06FP, is an ultra-fast recovery diode with a specification of 600V 8A in a TO-220FPAC package.
The high-voltage filter capacitor is from Chemi-Con and has a capacity of 82μF.
The LLC controller is from SanKen Electric, model SSC9522S, for half-bridge resonant switching power supplies with a built-in floating gate driver for high-side MOS tube drives. The chip enables a high-efficiency, low-noise, and cost-effective switching power supply solution, while the peripheral components are streamlined and available in an SOP18 package.
Fix the two switches on the heat sink.
开关管来自东芝，型号TK6A60D，NMOS，耐压600V，导阻1Ω。
The resonant capacitance specification is 0.033μF 1000V.
The transformer is wound with litz wire.
Two feedback optocouplers from Sharp, model PC123, are used for output voltage feedback.
Two Schottky diodes are fixed on the heat sink for rectification.
The Schottky rectifier is from ST ST, the model number is STPS2045CFP, the specification is 45V 20A, the two models are the same, and the TO-220FPAB package is used.
The output filter capacitor is from Ruby, which is a ZLJ series long-life electrolytic capacitor with a specification of 16V3900μF.
The switch for output control is from APEC Advanced, model AP6679BGH, PMOS, withstand voltage -30V, conduction resistance 9mΩ, and TO-252 package.
Two sampling resistors are used for output current sensing.
Four diodes are used for the rectification of the LED backlight boost circuit.
The two filter capacitors are from Ruby and are ZLH series long-life capacitors with a specification of 100V 82μF.
Underneath the heat sink is the LED dimming circuit.
The LED backlight driver chip is from ROHM, model BD9397EFV, built-in current mode boost controller and six constant current LED drivers, each channel output current is 400mA, the chip integrates LED open circuit and short circuit protection, integrated over-current protection and over-temperature protection, and is available in HTSSOP-B40 package.
The boost switch tube is provided with an aluminum heat sink and is secured by screws.
升压开关管来自APEC富鼎先进，型号AP20WN170I，NMOS，耐压200V，导阻170mΩ，采用TO-220CFM封装。
Close-up of the boost inductor.
Close-up of a backlit boost rectifier diode.
The filter capacitor is from Nichicon and is specified at 68μF 160V.
The standby power chip is from Infineon, silkscreen DDA010, and the chip has an integrated switch tube.
Close-up of standby power transformer.
Close-up of a rectifier diode used for standby power.
The filter capacitor is from Nichicon and is specified at 1000μF 10V.
A list of all dismantling and a family photo.
Summary of the dismantling of the charging head network
The Sony LCD TV power strip model is APDP-209A2, and this power strip is single-sided, using wave soldering process and single-sided soldering. The power devices of the power board are equipped with heat sinks, and hollow rivets are used for the pins of the corresponding high-current devices to increase the force area, reduce local stress, and avoid desoldering caused by temperature cycling.
Through the dismantling of the charging head network, it was learned that Delta's power board is composed of PFC+LLC architecture, the PFC controller is made of onsemi NCP1612, the LLC controller is SSC9522S Sanken Electric, the corresponding PFC switch and LLC switch are from Toshiba, and the PFC rectifier is from STMicroelectronics.
Schottky diodes are used for power output rectification, ROHM BD9397EFV are used for LED dimming, and the standby power chip is from Infineon. The power board is made of Japanese electrolytic capacitors as a whole, and the components are glued and reinforced, and the overall materials are well-known brands to ensure long-term stable and reliable use.