User's Manual

2. FUNCTIONAL DESCRIPTION
2.1 Block Diagram
Figure 12: STM 250 block diagram
2.1.1 Device power supply: Solar cell and Goldcap energy store
The extremely powerful solar cell has been designed especially for the STM 250 for maximum
unit performance at smallest dimensions. The active solar area is divided into two to provide
independent device power supplies:
a) Small active area: Main power supply
b) Big active area: Gold Cap charging supply
2.1.2 Power control
The power control supervises supply and charging status of the energy store. It controls the
power supply for wake-up timer, microprocessor and HF transmitter.
©EnOcean GmbH, A. Anders Page 10 of 24 STM 250 User Manual V1.3