Product Summary

The an294 is a Si825X frequency compensation simulator for digital buck converters. The an294 enables the user to easily design and optimize closed-loop frequency compensation for buck converters based on the Silicon Labs Si8250 digital power controller. The an294 simulates both the controller and power stages providing a single simulation of the entire system.The intuitive user interface of the an294 generates frequency response gain and phase graphs, and automatically generates filter coefficient values for the Si8250 in both decimal and hex formats. Applications of the an294 include: the Si8250/1/2 Digital Power Controller and Silicon Laboratories Single-phase POL Reference Design.

Parametrics

an294 absolute maximum ratings: (1) Input voltage: 10-15VDC; (2) Output voltage: 3.3VDC@20A max; (3) Switching frequency: 380 kHz ±2%; (4) Output inductor: 1 μH ±20% % (DCR: 1.5mΩ) ; (5) Output caps: 410μF±20% % (Capacitor ESR: 1.2mΩ) ; (6) RDS(on): 2.5mΩ; (7) Steady-State Bandwidth: ~35 kHz; (8) Transient BW: ~100 kHz; (9) Power efficiency: up to 92%; (10) Line Regulation: 0.42% (15A load) ; (11) Load Regulation: 0.3% (0~18A load) ; (12) Transient Response: 100mv under/overshoot, 20us recovery time, 5-10A, 2.5A/μs.

Features

an294 features: (1) System compensation design and optimization in a single intuitive simulation environment; (2) Directly generates compensation loop filter coefficients for the Si8250 digital controller; (3) Greatly reduces design and system verification time.

Diagrams

an294 Circuit