5 Power Management
The IC has four power domains:
- VS – Unregulated battery voltage input
- DVCC – Internally-regulated digital supply voltage. Typical value is 1.35V.
- AVCC – Internally-regulated RF front end and XTO supply. Typical value is 1.85V.
- VS_PA – Power amplifier supply: Depending on the battery voltage range (VS), the
following application modes are available:
- Connected externally to the battery in 3V applications (VS = VS_PA = 2.0V to 3.6V)
- Generated by an internal 3V
regulator in 3V/5V applications
- VS = 3.2V to 5.5V; VS_PA = 3V
- VS = 2.0V to 3.2V; VS_PA = VS – 200 mV
- Generated by an internal 2.2V
regulator in 3V/5V applications
- VS = 2.4V to 5.5V; VS_PA = 2.2V
- VS = 2.0V to 2.4V; VS_PA = VS – 200 mV
The device can be operated from VS = 2.0V to 3.6V (3V applications) and from VS = 2.4V to 5.5V (5V application). In the 5V application, an internal DC-DC converter can be activated to reduce the power consumption in the AVCC and VS_PA domain. In this case, the minimal VS voltage is 4.5V. The operating mode can be programmed in SUPCR.PVEN.