LM5170QPHPRQ1

The LM5170-Q1 controller provides the necessary high-voltage and precision components for dual-channel bidirectional converters in automotive 48V and 12V dual-battery systems. The device regulates average current between the high-voltage and low-voltage ports in the direction specified by the DIR input signal. The current regulation level can be programmed via analog or digital PWM inputs. Dual-channel differential current sense amplifiers and dedicated per-channel current monitors achieve typical current accuracy of 1%. Robust 5A half-bridge gate drivers can drive parallel MOSFET switches with power ratings of 500W/channel or higher. Diode emulation mode for synchronous rectifiers prevents negative current flow while also supporting improved light-load efficiency through discontinuous conduction mode. General protection features include cycle-by-cycle current limiting, HV and LV port overvoltage protection, MOSFET fault detection, and overtemperature protection. An innovative average current mode control scheme maintains constant loop gain, allowing a single R-C network to compensate both boost and buck conversions. The oscillator frequency is adjustable up to 500kHz and can be synchronized to an external clock. Two LM5170-Q1 controllers can be cascaded for 3-phase or 4-phase operation, or multiple controllers can be synchronized with phase-shifted clocks to achieve higher phase counts, enabling multiphase parallel operation. A logic-low state on the UVLO pin disables the LM5170-Q1 in a low-current shutdown mode.

Applications

• Dual-battery automotive systems
• Supercapacitor or backup battery power converters
• Stackable buck or boost converters

Key features

• AEC-Q100 qualified for automotive applications
• Device temperature grade 1: -40°C to +125°C ambient operating temperature range
• Device HBM ESD classification level 2
• Device CDM ESD classification level C4B
• Functional safety capable
• Documentation available to aid functional safety system design
• Maximum rated voltage of 100V and 65V for HV and LV ports respectively
• 1% precision bidirectional current regulation
• 1% precision channel current monitoring
• 5A peak half-bridge gate driver
• Programmable or adaptive dead-time control
• Programmable oscillator frequency with optional external clock synchronization
• 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 to prevent negative current
• Programmable soft-start timer
• MOSFET fault detection and circuit breaker control at startup
• Multiphase operation for phase adding/shedding