CY8CKIT-035 datasheet(9/49 Pages) ETC2

9 / 49 page

Figure 2-2 PME PCB (Bottom)

2.2 PSoC 4+1 Power Supervisor Solution on the PME

The PSoC Power Management EBK contains 4 DC voltage regulator circuits. They all have enable

inputs to allow PSoC to control the power up and power down sequencing of the regulators as well

as the necessary passive components to enable PSoC to measure their output voltage and load

currents using its built-in ADC converter. The regulators chosen support having their output voltage

trimmed (or margined) by PSoC and the necessary passive components to enable PSoC to detect

under and over voltage fault conditions using its internal window comparator hardware. PME EBK

also provides an I2C/SMBus/PMBus compatible header to support systems that have a requirement

for communication with a host controller. All of this functionality is implemented on a single PSoC

3. The PME routes all the input/output signals for power management/supervision to a PSoC 3

mounted on a development kit platform such as the CY8CKIT-001 PSoC Development Kit or

CY8CKIT-030 PSoC 3 Development Kit. PSoC 3 is not mounted on the PME EBK itself.

Figure 2-3 shows a high-level overview of the 4+1 Power Management solution that can be

implemented using the PME. Up to 4 secondary regulators can be sequenced through the logic-level

enable outputs (labeled as EN[4]). The 4 secondary voltage rails along with one primary input

power rail (labeled as V[4+1]) can be multiplexed into a 12 bit, differential Delta Sigma ADC

configured for a single-ended input range of 0-4096 mV at 27 ksps with a 0.1% accurate internal

reference. For load current measurements across a series shunt resistor (labeled as I[4+1]), the ADC

configuration is dynamically changed to a differential input range of ±256mV at 22.9 ksps. A

firmware interrupt service routine (ISR) running on PSoC is responsible for taking the raw ADC

readings and converting them to actual voltages (in mV) and currents (in μA), performing simple

IIR filtering and using this information to increase or decrease the duty cycles of the

CY8CKIT-035 Datenblatt(PDF) 9 Page - List of Unclassifed Manufacturers