Many of today’s embedded systems and advanced processors require controlled and choreographed sequencing as power supplies are powered up and applied to various circuits. Allowing for system flexibility and a simple approach to sequencing not only makes the system design easier, but it also enhances system reliability and allows for a single PMIC to handle a broader range of the system than just a specific processor’s requirements.
In summary, the main challenges facing the automotive infotainment system designer include the following:
- Balancing power dissipation with the high level of integration of multiple switching regulators and linear regulators
- Accurate output voltage regulation and load step response required by advanced nano-meter technology processors and FPGAs.
- Monitoring junction temperatures
- Immunity to radiated and conducted noise, with low emissions contributions
- Large voltage transients and temperature extremes
- Managing power sequencing during startup and shutdown
- Minimizing solution size and footprint.
A Simple Solution
Historically, many PMICs have not possessed the necessary power to handle these modern systems and microprocessors. Any solution to satisfy the automotive power management IC design constraints as already outlined must combine a high level of integration, including high-current switching regulators and LDOs, wide temperature range of operation, power sequencing and dynamic I2C control of key parameters with hard-to-do functional blocks. Furthermore, a device with high switching frequency reduces the size of external components and ceramic capacitors reduce output ripple. This low ripple combines with accurate, fast response regulators to satisfy demanding voltage tolerances of 45nm type processors. Such power ICs must also be capable of meeting the rigorous automotive environment including radiated emission