VESTEL MB120 DS, Service Manual

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Table 9: Pin functions.
B. TPS54628
General Description
The TPS54628 is an adaptive on-time D-CAP2 mode synchronous buck converter.The TPS54628 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 TPS54628 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 TSP54628 to maintain high efficiency during lighter load
conditions. The TPS54628 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 7 V. The device also features an adjustable soft start time. The TPS54628 is available in the 8-pin DDA and
10-pin DRC packages, and is designed to operate over the ambient temperature range of -40C to 85C.
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 7 V
•
Highly Efficient Integrated FETs Optimized for Lower Duty Cycle Applications- 36 mOhm (High Side)
and 28 mOhm (Low Side)
•
High Efficiency, less than 10 µA 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
•
Networking Home Terminal
•
Digital Set Top Box(STB)