TI公司的PMP15014是汽車信息娛樂電源系統參考設計,采用一級功率系統滿足高輸入電壓的需求,并提供不同負載的低壓多個輸出,還提供瞬態和極性相反保護,工作頻率2.1MHz,以避開AM頻段,具有優異的EMI性能.參考設備選用LM53625-Q1/LM53635-Q1同步降壓穩壓器.本文介紹了LM53625-Q1/LM53635-Q1主要特性,功能框圖,LM53635通用應用電路圖和幾種典型應用電路,以及汽車信息娛樂電源系統PMP15014主要特性,電路圖,材料清單和PCB設計圖.

　　The LM53625-Q1/LM53635-Q1 synchronous buck regulator is optimized for automotive applications， providing an output voltage of 5 V， 3.3 V， or an adjustable output. Advanced high-speed circuitry allows the LM53625-Q1/LM53635-Q1 to regulate from an input of 18 V to an output of 3.3 V at a fixed frequency of 2.1 MHz. Innovative architecture allows this device to regulate a 3.3-V output from an input voltage of only 3.55 V. All aspects of the LM53625-Q1/LM53635-Q1 are optimized for automotive and performance-driven industrial customers. An input voltage range up to 36 V， with transient tolerance up to 42 V， eases input surge protection design. The automotive-qualified Hotrod QFN package with wettable flanks reduces parasitic inductance and resistance while increasing efficiency， minimizing switch node ringing， and dramatically lowering electromagnetic interference （EMI）。 An open-drain reset output， with built-in filtering and delay， provides a true indication of system status. This feature negates the requirement for an additional supervisory component， saving cost and board space. Seamless transition between PWM and PFM modes and low quiescent current （only 15 μA for the 3.3 V option） ensure high efficiency and superior transient responses at all loads.

　　LM53625-Q1/LM53635-Q1主要特性：

　　AEC-Q100 Automotive Qualified：

　　Device Temperature Grade 1： –40℃ to +125℃ Ambient Operating Temperature Range

　　Device HBM Classification Level 2

　　Device CDM Classification Level C6

　　–40℃ to +150℃ Junction Temperature Range

　　15-μA Quiescent Current at no Load （Typical） with 3.3-V Output

　　4 mm × 5 mm， 0.5-mm Pitch VQFN Package WithWettable Flanks and 0.6-mm VIN Spacing

　　Low EMI and Switch Noise

　　Spread Spectrum Option

　　External Frequency Synchronization

　　RESET Output with Internal Filter and 3-ms Release Timer

　　Pin-Selectable Forced PWM Mode

　　Built-In Compensation， Soft Start， Current Limit， Thermal Shutdown， and UVLO

　　0.6-V Dropout at 3.5 A at 105℃ TA

　　±1% Output Voltage Tolerance （–40℃ to 125℃ TJ）

　　Available With Fixed 5-V， 3.3-V or Adjustable Output

圖1.LM53625-Q1/LM53635-Q1功能框圖

圖2.LM53635通用應用電路圖

圖3.LM53635固定5V/3.5A輸出電源電路圖

圖4.LM53635固定3.3V/3.5A輸出電源電路圖

圖5.LM53635 6V輸出電源電路圖

汽車信息娛樂電源系統PMP15014

This solution is designed to be an automotive off-battery front end power supply for infotainment systems. It was created using a one stage power system meeting high voltage input needs and providing low voltage for multi output rails for different load needs. The system also provides transient and reverse polarity protection. The Wide Vin Buck stage is? working at 2.1Mhz to avoid AM band and has superior? EMI performance with an differential? EMI filter to support CISPER 25.

　　圖6.汽車信息娛樂電源系統PMP15014外形圖

　　汽車信息娛樂電源系統PMP15014主要特性：

　　Wide Vin 2.1MHz Integrated ， Low Iq Buck Converter

　　Boost for 5V CAN supply

　　Transient and Reverse Polarity Protection and EMI filter added

　　The system disconnet the second stage power and keep 3.3V sustained when Input votlage lower than 4.5V

圖7.汽車信息娛樂電源系統PMP15014電路圖

汽車信息娛樂電源系統PMP15014材料清單:

圖8.PMP15014 PCB設計圖(1)

圖9.PMP15014 PCB設計圖(2)

圖10.PMP15014 PCB設計圖(3)

圖11.PMP15014 PCB設計圖(4)

圖12.PMP15014 PCB設計圖(5)

圖13.PMP15014 PCB設計圖(6)

圖14.PMP15014 PCB設計圖(7)

圖15.PMP15014 PCB設計圖(8)

圖16.PMP15014 PCB設計圖(9)