Precision Dual PWM Controller and Linear Regulator for Notebook CPUs
The IPM6210 is a highly integrated power controller that provides a complete power management solution for mobile CPUs. The IC integrates two PWM controllers and a linear regulator along with monitoring and protection circuitry into a single 28-lead plastic SSOP package. Two PWM controllers regulate the voltage of the microprocessor core and I/O synchronously rectified buck converter, while the linear regulators boost the CPU clock. The IPM6210 includes a 5-bit digital-to-analog converter (DAC) that adjusts the core PWM output voltage from 0.925VDC to 2.0VDC, compliant with Intel Mobile's VID specification. Operation of this DAC may change during setup to accommodate dual-mode processors. Special measures are provided to control the speed of such transition period within the specified 100µs. Precision reference, remote sensing technology and proprietary architecture, integrated processor mode compensates "droop" to provide good static and dynamic core voltage regulation. This second PWM controller has a fixed 1.5V output voltage and powers the I/O circuitry. There are two PWM controllers with integrated feedback loop compensation, which can significantly reduce the external component count. At rated load the PWM controller operates at a fixed frequency of 300kHz. At light loads, the filter inductor current becomes discontinuous and the controller operates in hysteretic mode. An external two-phase PWM controller to operate to reduce input current ripple is available in both modes of operation. The internal transfer device used by the linear regulator supplies the CPU clock generator to 2.5V. The IPM6210 monitors all output voltages. A single power good signal is issued, soft-start is complete and all outputs are within their respective ±10% set points. The overvoltage protection core and a built-in I/O output force the lower MOSFETs to prevent the output voltage from setting it to 115% above. The undervoltage protection lockout is turned off when any chip of the triple output drops below 75% of the set value. The PWM controller overcurrent circuit monitors the voltage drop across the output current sensing lower MOSFET. If accurate overcurrent protection is required, an external current sense resistor can optionally be used.