原标题：TI LM5170-Q1汽车48V和12V多相双向电流控制方案

　　TI公司的LM5170-Q1是多相双向电流控制器,为汽车48V和12V双电池系统提供双路双向转换器的高压和精密器件,在高压和低压端口间调整平均电流流动,电流调整水平通过模拟或数字PWM输入进行编程,精度1%,满足汽车AEC-Q100规范,工作温度–40°C到+125°C,主要用在汽车双电池系统,超级电容或电池备份电源转换器,以及可堆栈降压或升压转换器.本文介绍了LM5170-Q1主要特性,框图和应用电路,以及评估板LM5170EVM-BIDIR主要特性和电性能,电路图,材料清单和PCB设计图.

　　The LM5170-Q1 controller provides the essential highvoltage and precision elements of a dual-channelbidirectional converter for automotive 48-V and 12-Vdual battery systems. It regulates the average currentflowing between the high voltage and low voltageports in the direction designated by the DIR inputsignal. The current regulation level is programmedthrough analog or digital PWM inputs.

　　Dual-channel differential current sense amplifiers anddedicated channel current monitors achieve typicalcurrent accuracy of 1%. Robust 5-A half-bridge gatedrivers are capable of driving parallel MOSFETswitches delivering 500 W or more per channel. Thediode emulation mode of the synchronous rectifiersprevents negative currents but also enables

　　discontinuous mode operation for improved efficiencywith light loads. Versatile protection features includecycle-by-cycle current limiting, overvoltage protectionat both HV and LV ports, MOSFET failure detectionand overtemperature protection.

　　An innovative average current mode control schememaintains constant loop gain allowing a single R-Cnetwork to compensate both buck and boostconversion. The oscillator is adjustable up to 500 kHzand can synchronize to an external clock. Multiphaseparallel operation is achieved by connecting twoLM5170-Q1 controllers for 3 or 4-phase operation, orby synchronizing multiple controllers to phase-shiftedclocks for a higher number of phases. A low state onthe UVLO pin disables the LM5170-Q1 in a low

　　current shutdown mode.

　　LM5170-Q1主要特性:

　　1• AEC-Q100 Qualified for Automotive Applications:

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

　　– Device HBM ESD Classification Level 2

　　– Device CDM ESD Classification Level C4B

　　• 100-V HV-Port and 65-V LV-Port Max Ratings

　　• 1% Accurate Bidirectional Current Regulation

　　• 1% Accurate Channel Current Monitoring

　　• 5-A Peak Half-Bridge Gate Drivers

　　• Programmable or Adaptive Dead-Time Control

　　• Programmable Oscillator Frequency With OptionalSynchronization to External Clock

　　• Independent Channel Enable Control Inputs

　　• Analog and Digital Channel Current Control Inputs

　　• Programmable Cycle-by-Cycle Peak Current Limit

　　• HV and LV Port Overvoltage Protection

　　• Diode Emulation Prevents Negative Current

　　• Programmable Soft-Start Timer

　　• MOSFET Failure Detect at Start-Up and CircuitBreaker Control

　　• Multiphase Operation Phase Adding or Dropping

　　LM5170-Q1应用:

　　• Automotive Dual Battery Systems

　　• Super-Cap or Battery Backup Power Converters

　　• Stackable Buck or Boost Converters

　　图1.LM5170-Q1功能框图

　　图2.LM5170-Q1双相双向转换器

　　评估板LM5170EVM-BIDIR

　　The LM5170EVM-BIDIR is a high performance dual phase bi-directional converter ideal for 48V-12V dual battery system applications. The two phases operate in 180degree interleaved operation, and they evenly share a max dc current of up to 60A. When DIR is set to "1" the power flows from the 48V port to the 12V port, and the 12V port voltage is regulated at abtou 14.5V. When DIR is set to "0" the power flows from the 12V port to the 48V port, 48V port voltage is regulated at abtou 50.5V. The EVM also includes various jumpers to flexiblely and conveniently configure the circuit to fit for many different use cases, including the capable of being controlled by MCU, high power unidirectional buck or boost converters, etc.

　　评估板LM5170EVM-BIDIR主要特性和电性能:

　　• Input Operating Voltage Ranges

　　– The 48VDC-Port 6 V to 75 V, in the Buck Mode

　　– The 12VDC-Port 3 V to 48 V, in the Boost Mode

　　• Output Voltage Regulation (With the Onboard Outer Voltage Loop Control Activated)

　　– 14.5-V Output Voltage at the 12VDC-Port, in the Buck Mode

　　– 50.5-V Output Voltage at the 48VDC-Port, in the Boost Mode

　　• Operating Current

　　– 60-Adc Maximum from or into the 12VDC-Port

　　– Typical 1% Current Regulation Accuracy

　　– Typical 1% Current Monitor Accuracy

　　• Switching Frequency:

　　– Standalone Fsw = 100 kHz

　　– Able to Synchronize to an External Clock from 80 kHz to 120 kHz.

　　• Maximum Efficiency: >97%

　　• OVP Threshold

　　– 75 V at the 48VDC-Port

　　– 22 V at the 12VDC-Port

　　– Synchronous Rectifier Diode Emulation Function Preventing Negative Current

　　• Other Convenient Features

　　– Optional Onboard Wide-VIN™ LM5118-Q1 Buck-Boost Converter as the +10-V Supply

　　– Onboard Ultra Low IQ TPS709-Q1 LDOs for +3.3-V and +5.0-V Bias Voltages for Convenient EVMConfigurations and for Biasing the External MCU through Headers.

　　– Onboard LM26LV Temperature Sensors Monitoring Local Temperatures of Power MOSFETs, WithOptional Overtemperature Shutdown and LED Indicator.

　　– LED indicators of Buck and Boost Operating Modes.

　　– Optional Channel Current Shunt AC Filters for Accurate DVM Reading (Unpopulated).

　　评估板LM5170EVM-BIDIR特性:

　　Buck Mode: 48V-port voltage range 6V to 75V; 12V-port voltge regulated at 14.5V

　　Boost Mode: 12V-port voltage range 3V to 48V; 48V-port voltge regulated at 50.5V

　　Max dc current into or out of the 12V-port is 60A

　　Built-in analog voltage loop control, while it also accept MCU digital voltage loop control through interface connectors

　　Daisy chain multi phase capable for interleaved 3, 4, 6, 8 phases operation to support higher power

　　图3.评估板LM5170EVM-BIDIR外形图:48V-12V双向转换器

　　评估板LM5170EVM-BIDIR材料清单: