CC1021-RTR1 datasheet(56/91 Pages) TI1

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Not Recommended for New Designs NRND

CC1021

SWRS045D – JANUARY 2006 – REVISED JANUARY 2015

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5.19.2 General Purpose Output Control Pins

The two digital output pins, PA_EN and LNA_EN, can be used as two general control signals by setting

EXT_PA = 0 and EXT_LNA = 0. The output value is then set directly by the value written to EXT_PA_POL

and EXT_LNA_POL.

The LOCK pin can also be used as a general-purpose output pin. The LOCK pin is controlled by

LOCK_SELECT[3:0] in the LOCK register. The LOCK pin is low when LOCK_SELECT[3:0] = 0000, and

high when LOCK_SELECT[3:0] = 0001.

These features can be used to save I/O pins on the microcontroller when the other functions associated

with these pins are not used.

5.19.3 PA_EN and LNA_EN Pin Drive

Figure 5-32 shows the PA_EN and LNA_EN pin drive currents. The sink and source currents have

opposite signs but absolute values are used in Figure 5-32.

Figure 5-32. PA_EN and LNA_EN Pin Drive

5.20 System Considerations and Guidelines

5.20.1 SRD Regulations

International regulations and national laws regulate the use of radio receivers and transmitters. SRDs

(Short Range Devices) for license free operation are allowed to operate in the 433 and 868 to 870 MHz

bands in most European countries. In the United States, such devices operate in the 260 to 470 and 902

to 928 MHz bands. A summary of the most important aspects of these regulations can be found in

Application Note AN001 SRD Regulations for License Free Transceiver Operation (SWRA090).

Detailed Description

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CC1021-RTR1 Datasheet(PDF) 56 Page - Texas Instruments