PowerintLCS701HG125WLCDTV Power Solution (DER-270)

PowerInt’s HiperLCS family features a multi-function controller, high-side and low-side gate drivers, and an integrated LLC power stage with two half-bridge connected power MOSFETs, saving up to 30 external components, and operating at a maximum frequency of 1MHz. Steady-state operating frequency up to 500kHz, full load efficiency up to 98%, mainly used in high-efficiency power supplies (80+ silver, gold and platinum), LCD TV power supplies, LED block and area cooperative lighting, printer power supplies and audio amplifier power supplies. This article introduces HiperLCS series main features, block diagram, LCD TV and PC main power application Circuit diagram, 150 W laser printer power supply and 125 W LCD TV power supply circuit diagram with LCS701HG, bill of materials and PCB layout.

The HiperLCS is an integrated LLC power stage incorporating a multi-function controller, high-side and low-side gate drivers, plus two power MOSFETs in a half-bridge configuration. Figure 1 shows a simplified schematic of a HiperLCS based power stage where the LLC resonant Inductor is integrated into the transformer.

The variable frequency controller provides high efficiency by switching the power MOSFETs at zero voltage (ZVS), eliminating switching losses.

Main features of HiperLCS series:

• LLC half-bridge power stage incorporating controller, high and low-side gate drives, and high-voltage power MOSFETs

• Eliminates up to 30 external components

• High maximum operating frequency of 1 MHz

• Nominal steady-state operation up to 500 kHz

• Dramatically reduces magnetics size and allows use of SMD ceramic output capacitors

• Precise duty symmetry balances output rectifier current, improving efficiency

• 50% ±0.3% typical at 300 kHz

• Comprehensive fault handling and current limiting

• Programmable brown-in/out thresholds and hysteresis

• Undervoltage (UV) and overvoltage (OV) protection

• Programmable over-current protection (OCP)

• Short-circuit protection (SCP)

• Over-temperature protection (OTP)

• Programmable dead-time for optimized design

• Programmable burst mode maintains regulation at no-load and improves light load efficiency

• Programmable soft-start time and delay before soft-start

• Accurate programmable minimum and maximum frequency limits

• Single package designed for high-power and high-frequency

• Reduces assembly cost and reduces PCB layout loop areas

• Simple single clip attachment to heat sink

• Exposed thermal pad connected to ground potential – no insulators required between package and heat sink

• Staggered pin arrangement for simple PC board routing and high-voltage creepage requirements

• Paired with HiperPFS PFC product gives complete, high efficiency, low part count PSU solutions

HiperLCS series applications:

• High-efficiency power supplies (80 PLUS Silver, Gold and Platinum)

• LCD TV power supplies

• LED street and area lighting

• Printer power supplies

• Audio amplifier

Figure 1. HiperLCS Series Block Diagram

Figure 2. HiperLCS series LCD TV and PC main power application circuit diagram

Figure 3. 150 W Laser Printer Power Supply

125 W LCD TV Power Supply with LCS701HG

125 W LLC DC-DC Resonant converter Using HiperLCSTM LCS701HG

This document is an engineering report describing a 12 V and 24 V, 125 W LLC DC-DC converter utilizing a LCS701HG integrated LLC power stage IC. This power supply is intended as for use in an LCD TV with LED back lighting. The board requires 12 VDC and 380 VDC inputs.

The document contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.

125 W LCD TV power supply main features:

Low Profile Design

11 mm height idea for low profile LCD TV designs

Low part count solution

Integration of controller, drivers and MOSFET half bridge in a single HiperLCS IC
dramatically reduces component count and complexity

High Operating Frequency (190 kHz)

Enabled use of ceramic output capacitors

Enabled use of low profile EFD35 core size

High Performance

>94% full load efficiency

Excellent output cross regulation

Lossless capacitive current sense for reduced losses

Burst mode ensures regulation under no-load condition

Figure 4. 125 W LCD TV Power Supply Outline Drawing (Top View: 2.97” x 5.8” (75.44 mm x 147.32 mm))
1125 W LCD TV Power Specifications:


Figure 5. 125 W LCD TV power supply circuit diagram
125 W LCD TV Power Supply Bill of Materials (BOM):



Figure 6. Power Transformer Circuit Diagram
Main indicators of power transformer:


Figure 7. 125 W LCD TV Power Supply PCB Layout (Top Layer) (Dimensions in Mils)

Figure 8. 125 W LCD TV power supply PCB layout (bottom layer)
For details, see:
http://www.powerint.com/sites/default/files/product-docs/hiperlcs_family_datasheet.pdf
and
http://www.powerint.com/sites/default/files/PDFFiles/der270.pdf