ZHCSGB0B November 2017 – November 2020 LM5145
PRODUCTION DATA
Measuring the voltage drop across the low-side MOSFET or with an optional current sense resistor gives cycle-by-cycle overcurrent protection. The LM5145 voltage-mode controller with line feedforward drives external high-side and low-side N-channel power switches with robust 7.5-V gate drivers suitable for standard-threshold MOSFETs. Adaptively-timed gate drivers with 2.3-A source and 3.5-A sink capability minimize body diode conduction during switching transitions, reducing switching losses and improving thermal performance when driving MOSFETs at high input voltage and high frequency. The LM5145 can be powered from the output of the switching regulator or another available source, further improving efficiency.
A 180° out-of-phase clock output relative to the internal oscillator at SYNCOUT works well for cascaded or multi-channel power supplies to reduce input capacitor ripple current and EMI filter size. Additional features of the LM5145 include a configurable soft start, an open-drain power-good monitor for fault reporting and output monitoring, monotonic start-up into prebiased loads, integrated VCC bias supply regulator and bootstrap diode, external power supply tracking, precision enable input with hysteresis for adjustable line undervoltage lockout (UVLO), hiccup-mode overload protection, and thermal shutdown protection with automatic recovery.
The LM5145 controller is offered in a 4.5-mm × 3.5-mm thermally enhanced, 20-pin VQFN package with additional spacing for high-voltage pins and wettable flanks for optical inspection of solder joint fillets.