ST STP4CMP帶電荷泵四路LED驅動解決方案

關鍵詞： LED驅動 , ST , STP4CMP , 電荷泵

ST公司的STP4CMP是基于電荷泵的四路LED驅動器,設計用于RGB照明或LCD顯示器背光.支持正向電壓高達成3.8V的LED,工作電壓 2.7 V到5.5 V,四路電流可單獨編程,最大電流30mA,輸出電流精度 ±7%,通路間電流匹配度在 ±4%內.主要用在手機顯示器背光和RGB LED指示器驅動器.本文介紹了STP4CMP主要特性,框圖,典型應用電路及其所用元件,STP4CMP評估板及其電路圖,STEVAL-TLL012V1演示板主要特性和電路圖,材料清單.

The STP4CMP is a charge pump based 4-channel LED driver designed for RGB illumination or LCD display backlighting. The STP4CMP works off a battery with an input voltage between 2.7 V - 5.5 V. The device generates regulated current sinks with high absolute and channel-tochannel accuracy to drive up to 4 LEDs. It can support LEDs with forward voltage as high as 3.8 V. The current sink for each channel can be set with 4 individual external resistors. Each channel is controlled independently. The PWM control can be applied directly to the 4 EN (enable) pins to provide brightness control. When enabled, the charge pump, which uses a small ceramic bucket capacitor between C1P and C1N, operates to regulate the VOUT with a clamping voltage at typ.

5 V. The tiny QFN20 (1.8 x 3.2 mm) package allows the device to be also used for applications with space limitation.

STP4CMP主要特性:

■ Operating voltage range: VCC (opr) = 2.7 V to 5.5 V

■ Full RGB function support

■ 4-channel LED driver with individual ON/OFF control directly from input pins

■ Individual programmable output current for the 4 channels through 4 external resistors with a max. capability of 30 mA

■ Absolute output current accuracy of max. ±7% and channel-to-channel mismatch of max. ± 4%

■ Selectable charge pump enable/disable

■ Thermal protection

■ Small QFN20 (1.8 x 3.2 mm) package

STP4CMP應用:

■ Mobile phone display backlighting

■ RGB LED indicator drivers

2012-7-9 11:26:32 上傳

下載附件 (26.05 KB)

圖1.STP4CMP方框圖

2012-7-9 11:26:32 上傳

下載附件 (13.36 KB)

圖2.STP4CMP應用框圖
圖2應用電路外接元件:

2012-7-9 11:26:32 上傳

下載附件 (26.33 KB)

2012-7-9 11:22:41 上傳

下載附件 (87.32 KB)

圖3.STP4CMP評估板外形圖

2012-7-9 11:26:32 上傳

下載附件 (31.87 KB)

圖4.STP4CMP評估板電路圖

STEVAL-TLL012V1演示板

The STEVAL-TLL012V1 demonstration board demonstrates the performance of the STP4CMP, a charge pump based 4-channel LED driver designed for RGB illumination or LCD display backlighting.

This device works off a battery with an input voltage between 2.7 V - 5.5 V. The device generates regulated current sinks with high absolute and channel-to-channel accuracy to drive up to 4 LEDs. It can support LEDs with forward voltage as high as 3.8 V.

The current sink for each channel can be set with 4 individual external resistors. Each channel is controlled independently.

The PWM control can be applied directly to the 4 EN (enable) inputs to provide brightness control.

STEVAL-TLL012V1演示板主要特性:

■ Operating voltage range: 2.7 V to 5.5 V

■ Full RGB function support

■ 4-channel LED driver with individual ON/OFF control directly from input pins

■ Individual programmable output current for the 4 channels through 4 external resistors with a max. capability of 30 mA

■ Absolute output current accuracy of max. ±7% and channel-to-channel mismatch of max. ± 4%

■ Selectable charge pump enable/disable

■ Thermal protection

■ RoHS compliant

2012-7-9 11:22:41 上傳

下載附件 (74.58 KB)