The ISL6560 two-phase current mode, PWM controlled IC with matching gate drivers, HIP6601A, HIP6602A, HIP6603A or HIP6604 and mosfet provide accurate voltage regulation systems for advanced microprocessors. Two-phase power conversion differs markedly from the single-phase converter configurations previously used to meet the increasing current demands of modern microprocessors.
Block Diagram
Polyphase converters produce smaller, lower-cost transistors and fewer input and output capacitors by distributing power and load current. Due to the phase interleaving process of this topology, a higher effective conversion frequency and a higher frequency ripple current are generated. For example, a two-phase converter operating at 350kHz per phase will have a ripple frequency of 700kHz. Higher converter bandwidth can also be achieved, resulting in faster response to load transients. A prominent feature of the controller IC includes high side current sensing, a single current sampling resistance at the input line to the output MOSFET transistor.
Pinout
This single current sampling resistor monitors the input current in each channel, ensuring good current sharing. Current mode control results in rapid response to changing load demands. It also has a programmable VID code with an accuracy of ±0.8%, a range of 1.100-1.850V, and is set by the microprocessor.
The pull-up current on these VID pins eliminates the need for an external pull-up resistance. Another feature of the controller IC is the PWRGD monitoring circuit and load protection circuit, providing overvoltage protection, overcurrent protection and undervoltage indication.
Global circuit description