1.5.2 Typical Stand-Alone Application

Figure 1-4. Typical 3V Stand-Alone Application

Note:

This connection depends on the setting of the bits VS5V and VS22; see the sysConfig register.

The preceding figure shows a stand-alone remote control application circuit for 315 MHz or 433.92 MHz running from a 3V lithium cell. The ATA8510 stays in OFFMode until one of the NPWRON ports PC1..PC5 is pulled to ground level, waking up the circuit. The NPWRON ports PC1..PC5 have internal 50-kΩ pull-up resistors and can be left open if not used.

The user application software within the 20-Kbyte Flash (ATA8510) is used to control the ATA8510 transceiver together with the firmware in the 24-Kbyte ROM. The ATA8515 is not suitable for this application. The RF and decoupling circuitry is similar to Figure 1-3.

In this application, an LED is connected to PB7. Alternatively, an additional wake-up button can be used on PB7 instead of an LED. An LED can also be connected to PB4. However, note the additional pull-down resistor connected in parallel that is needed to prevent transverse currents in OFFMode. This special case only applies to PB4 because of its active input characteristics (PWRON).