Controlling the Output Power from CC2590

Input Levels on Control Pins

Connecting CC2590 to a CC24xx Device

RF_P

RXTX

RF_N

RF_P

TXRX_SWITCH

RF_N

CC24xx

RREG_OUT (CC243x,CC2480),

VREGOUT (CC2420),GIO1(CC2400)

Alternatively

VDD/GND

to

/MCU

(CC2420)

Alternatively

fromMCU

RF_P

RXTX

RF_N

= PCBtraceinductor

CC2590

ANT

PAEN

EN

HGM

VDD

VDD

VDD

RF_P

RXTX

RF_N

L112

C113

C111

L111

C112

C161

C101/C102

C131/C132

R151

P1_1(CC243x),GPIO1(CC2480),

GIO6(CC2400)

L21

CC2590

The output power of CC2590 is controlled by controlling the input power. The CC2590 PA is designed to work in

compression (class AB), and the best efficiency is reached when a strong input signal is applied.

The four digital control pins (PAEN, EN, HGM, RXTX) have built-in level-shifting functionality, meaning that if the

CC2590 is operating from a 3.6-V supply voltage, the control pins will still sense 1.6-V - 1.8-V signals as logical

‘1’.

An example of the above would be that RXTX is connected directly to the RXTX pin on CC24xx, but the global

supply voltage is 3.6-V. The RXTX pin on CC24xx will switch between 0-V (RX) and 1.8-V(TX), which is still a

high enough voltage to control the mode of CC2590.

The input voltages should however not have logical ‘1’ level that is higher than the supply.

Table 3. Control Logic for Connecting CC2590 to a CC24xx Device

PAEN = EN

RXTX

HGM

MODE OF OPERATION

0

X

X

Power Down

1

0

0

RX Low Gain Mode

1

0

1

RX High Gain Mode

1

1

X

TX

Figure 11. CC2590 + CC24xx Application Circuit

Copyright © 2008, Texas Instruments Incorporated

Submit Documentation Feedback

9

Product Folder Link(s): CC2590