Hitachi 55293DLB, Service Manual

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17
24V(VDD_Audio) goes directly to the audio side, through power socket other incoming voltages from
power card are converted several voltages, shown in figure 8.
List of the components are:

TPS54528

TPS54328

TPS54821

TPS51363

APL5910

LM1117
TPS54528
General Description
The TPS54528 is an adaptive on-time D-CAP2 mode synchronous buck converter.The TPS54528 enables
system designers to complete the suite of various end-equipment power bus regulators with a cost effective, low
component count, low standby current solution. The main control loop for the TPS54528 uses the D-CAP2
mode control that provides a fast transient response with no external compensation components. The adaptive
on-time control supports seamless transition between PWM mode at higher load conditions and Eco-mode
operation at light loads. Eco-mode allows the TSP54528 to maintain high efficiency during lighter load
conditions. The TPS54528 also has a proprietary circuit that enables the device to adopt to both low equivalent
series resistance (ESR)output capacitors, such as POSCAP or SP-CAP, and ultra-low ESR ceramic capacitors.
The device operates from 4.5-V to 18-V VIN input. The output voltage can be programmed between 0.76 V
and 6 V. The device also features an adjustable soft start time. The TPS54528 is available in the 8-pin DDA
package, and designed to operate from -40 C to 85 C.
Features

D-CAP2 Mode Enables Fast Transient Response

Low Output ripple and Allows Ceramic Output Capacitor

Wide V
IN
Input Voltage Range: 4.5 V to 18 V

Output Voltage Range: 0.76 V to 6 V

Highly Efficient Integrated FETs Optimized for Lower Duty Cycle Applications- 65 mOhm (High Side)
and 36 mOhm (Low Side)

High Efficiency, less than 10 mikroAmper at shutdown

High Initial Bandgap Reference Accuracy

Adjustable Soft Start

Pre-Biased Soft Start

650-kHz Switching Frequency (f
SW
)

Cycle By Cycle Over Current Limit

Auto-Skip Eco-mode for High Efficiency at Light Load
Applications

Wide Range of Applications for Low Voltage System

Digital TV Power Supply

High Definition Blu-ray Disc Players