Different blocks in the DVD player system require different DC supply voltages to power them. For example, logic circuitry may require 5V, DSP, MCU and memory chips may require 3.3V, motors in DVD/CD drives mechanisms may need 12V and fluorescent displays may require +/-36V. Designing an optimal power supply for DVD players can be challenging as the required power consumption can change rapidly within a small interval, for instance, while playing music. So, the power supply should save power by not delivering the maximum output power continuously while also not compromising on sound quality. Required power supply voltage, peak and average powers, efficiency, cost, size and weight are some factors affecting the design.
Commonly, the DVD power supply is designed to take a universal input voltage and supplies different DC voltages to various sub-systems, though this can vary slightly depending on a particular type of player. New generation monolithic AC-DC converters use advanced PWM controllers and MOSFETs, which increase efficiency and reduce power consumption. Many designs implement several interesting protection mechanisms such as brownout detection (which does not allow operation in low mains conditions), over load protection, overvoltage protection and under voltage protections. Special efforts are made to build a design conforming to tighter industry standards of efficiency and low standby power consumptions.
Want to design your own power supply for a DVD player? Get here some ready-to-use reference designs from the industry:-
- Multiple output 7W DVD Player/Set-top Box Supply: Here is a reference design from Power Integrations which implements a multiple output Flyback power supply for DVD players or set-top boxes with 7 W of continuous output power and 10 W of peak power. Based on a LNK626PG AC-DC converter from Power Integrations, the supply is highly energy efficient (provides 0.6 W output for 1 W input) and has low no-load power consumption. The design eliminates optocoupler and reduces part count. More on this Reference Design
- Low cost 8W Supply: Here is Onsemi’s low-cost DVD player power supply reference design which takes universal input voltage and produces 5 different DC voltages of 5V, 3.3V, 12V, -12V and -23V. The design uses a current-mode flyback regulator built around integrated power switcher, the NCP1027 from ON semiconductor. The design offers low standby power, brown−out detection, ramp compensation, over power protection and latch−off Input (complete latch−off in presence of an external event, e.g. over temperature or a severe over−voltage). More on this Reference Design
- High-efficiency DVD or Set-top Box Supply: This is Freescale’s reference design for a DVD or set-top box power supply with universal input and 4 different DC outputs, namely, 5.1V, 3.4V, 12V and 16V. The design claims low standby consumption, low EMI, high efficiency under voltage lockout and various protections such as overvoltage protection (OVP), overload protection (OLP), abnormal overcurrent protection (AOCP) and internal thermal shutdown (TSD). More on this Reference Design
- Energy Star Compliant Low-cost DVD Player Supply: ST has developed a reference design implementing a DVD player power supply with multiple outputs for a variety of control circuits: MCU, motor, amplifier and VFD. The design is based on Offline switch mode power supply (SMPS) regulators from ST’s VIPer family to develop an innovative, quicker, cheap and simple AC-DC converter with reduced component count. The VIPer family complies with the “Blue Angel” and “Energy Star” norms, with very low total power consumption in standby mode. More on this Reference Design