Maxim 公司的MAX16929是用于汽车TFT-LCD的高度集成电源器件,它集成了一个降压转换器,一个升压转换器,一个1.8V/3.3V稳压控制器和两个栅极电压稳压器.工作电压4V-28V(降压)或3V-5.5V(升压),高达6W的升压输出达18V,高频开关工作:2.1MHz (降压转换器),2.2MHz (升压转换器),主要用在汽车仪表盘,汽车导航系统和汽车中心信息显示器.本文介绍了MAX16929主要特性,方框图, 典型应用电路图和MAX16929评估板主要特性,电路图和材料清单.

The MAX16929 is a highly integrated power supply for automotive TFT-LCD applications. The device integrates one buck converter, one boost converter, one 1.8V/3.3V regulator controller, and two gate voltage regulators. The device comes in several versions to satisfy com­mon automotive power-supply requirements.

Designed to operate from a single 4V to 28V supply or 5.5V to 28V supply, the device is ideal for automotive TFT-LCD applications.

Both the buck and boost converters use spread-spec­trum modulation to reduce peak interference and to opti­mize EMI performance.

The sequencing input (SEQ) allows flexible sequencing of the positive-gate and negative-gate voltage regulators. The power-good indicator (PGOOD) indicates a failure on any of the converters or regulator outputs. Integrated thermal shutdown circuitry protects the device from over­heating.

The MAX16929 is available in a 28-pin TSSOP pack­age with exposed pad, and operates over the -40NC to +105NC temperature range.

MAX16929主要特性:

Operating Voltage Range of 4V to 28V (Buck) or 3V to 5.5V (Boost)

Independent 28V Input Buck Converter Powers TFT Bias Supply Circuitry and External Circuitry

High-Power (Up to 6W) Boost Output Providing Up to 18V

1.8V or 3.3V Regulator Provides 500mA with External npn Transistor

One Positive-Gate Voltage Regulator Capable of Delivering 20mA at 28V

One Negative-Gate Voltage Regulator

High-Frequency Operation 2.1MHz (Buck Converter) 2.2MHz (Boost Converter)

Flexible Stand-Alone Sequencing

True Shutdown™ Boost Converter

6μA Low-Current Shutdown Mode (Buck)

Internal Soft-Start

Overtemperature Shutdown

-40NC to +105NC Operation

MAX16929应用:

Automotive Dashboards

Automotive Central Information Displays

Automotive Navigation Systems

图1.MAX16929升压转换器功能框图

图2.MAX16929典型应用电路图

MAX16929评估板

The MAX16929 evaluation kit (EV kit) is a fully assembled and tested surface-mount PCB that provides the voltages and features required for automotive thin-film transistor (TFT), liquid-crystal display (LCD) applications. The EV kit includes one step-down and one step-up switching regulator, one positive gate and one negative gate volt­age regulator, one 3.3V regulator controller with external npn transistor, and one positive and one negative charge pump.

The EV kit can operate from 4.5V to 28V input voltages and is optimized for automotive TFT-LCD applications. The step-down switching regulator is configured for a 5V output that provides at least 1.2A. The step-up switching regulator is configured for a 12V output that provides at least 500mA. The positive gate voltage regulator pro­vides 18V output and the negative gate voltage regulator provides -6.2V.

MAX16929评估板主要特性:

4.5V to 28V Input Range

Output Voltages

5V Output at 1.2A (Step-Down Switching Regulator)

12V Output at 500mA (Step-Up Switching Regulator)

3.3V Output at 500mA (Regulator Controller)

18V Output (Positive Gate Voltage Regulator)

-6.2V Output (Negative Gate Voltage Regulator)

High-Frequency Operation

2.1MHz (Buck Converter)

2.2MHz (Boost Converter)

Adjustable Positive and Negative Charge Pumps

Proven PCB Layout

Fully Assembled and Tested


图3. MAX16929评估板电路图
MAX16929评估板材料清单:




图4.MAX16929评估板PCB布局图
详情请见:
http://datasheets.maxim-ic.com/en/ds/MAX16929.pdf
和
http://datasheets.maxim-ic.com/en/ds/MAX16929EVKIT.pdf