本論文探討升壓型穩壓器應用於可調光發光二極體驅動器之議題，內文分為兩部份，第一部份針對電流模式控制之切換式升壓穩壓器，建立系統性的設計與分析流程，包含系統模型、補償器設計、電晶體層次設計、晶片下線，最後藉由晶片量測結果來驗證此設計流程的正確性。量測結果證明在輸入電壓於4.2~5.5V的鋰電池供電範圍內，在30mA~330mA負載電流範圍內，此轉換器可以穩定的提供36V的輸出電壓，暫態響應約為80μs，最高轉換效率為89.4 %。藉由頻域量測，驗證了本設計與分析流程的正確性，同時證明系統的穩定性。本電流模式控制升壓轉換器使用TSMC 0.25μm HVCMOS製程進行設計，外接電感與輸出電容分別為22μH與2.2μF。
第二部份提出了具混合調光功能之白光發光二極體驅動器，此驅動器採用電流模式控制升壓轉換器為前端電壓驅動電路，後端電路為混合調光機制電路，整合了類比、數位調光功能，不僅有效降低晶片封裝腳數，亦減少額外的調光控制線路之繞線複雜度，以上兩點均可降低晶片成本。晶片量測以發光二極體為負載，其單顆功率小於1 W，驅動電壓與全亮度電流分別為2.8V與100mA。於輸入電壓4.2~12V條件下，可觀測到隨著輸入類比/數位之調光訊號大小，發光二極體有明顯亮暗之差，驗證了混合調光之功能，其中數位調光頻率最大可達100k Hz，最高轉換效率為88.2%。

This study addressed the issue of driving WLED by a boost regulator with dimming function. This thesis is composed of two parts. The first part focuses on the current-mode control switching boost regulator. Systematic design procedure and analysis flow are presented with system modeling, compensator design, transistor level design and chip implementation. The design procedure is verified by the chip’s measurement results. The measurement result show that this converter can operate with load current from 30mA-330mA in a supply voltage from 4.2-5.5V and the output voltage of 36V. The transient response time is about 80μs and the highest efficiency is 89.4%. By the loop gain measurement, the correctness of the analysis flow is verified. The stability of proposed buck converter was guaranteed by the loop gain measurement, too. This converter has been designed and fabricated with TSMC 1P6M 0.25μm HVCMOS process. The off chip inductor and the output capacitor are 22μH and 2.2μF.
The second part proposed a white light emitting diode driver with hybrid dimming. The driver used a current-mode controlled boost converter as the pre-regulator. And the hybrid dimming approach is proposed for processing both analog and digital dimming signals using only one pin. This technique reduces the wire routing complexity and the cost of footpins. Use WLED as load in chip measurement, with power dissipation lower than 1 Watt of each. And the forward voltage and forward current are 2.8 Volt and 100mA, respectively. Within VIN ranging of 4.2-12V, the luminance of WLEDs will change by analog or digital dimming signal. The hybrid dimming function is verified. The max PWM dimming frequency is 100k Hz and the highest conversion efficiency is 88.2%.

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