User Manual

Revision 1.0 Page 22 of 78
nRF24L01+ Product Specification
.
Figure 4. Radio control state diagram
6.1.2 Power Down Mode
In power down mode nRF24L01+ is disabled using minimal current consumption. All register values avail-
able are maintained and the SPI is kept active, enabling change of configuration and the uploading/down-
loading of data registers. For start up times see Table 16. on page 24
. Power down mode is entered by
setting the PWR_UP bit in the CONFIG register low.
6.1.3 Standby Modes
6.1.3.1 Standby-I mode
By setting the PWR_UP bit in the CONFIG register to 1, the device enters standby-I mode. Standby-I mode is
used to minimize average current consumption while maintaining short start up times. In this mode only
part of the crystal oscillator is active. Change to active modes only happens if CE is set high and when CE
is set low, the nRF24L01 returns to standby-I mode from both the TX and RX modes.
VDD >= 1.9V
Undefined
Power on
reset
100ms
Power Down
Standby-I
RX Mode
TX Mode
Standby-II
RX Settling
130 µs
Crystal
oscillator
start up
Tpd2stby
PWR_UP = 1
PWR_UP = 0
TX Settling
130 µs
TX FIFO not empty
PRIM_RX = 0
CE = 1 for more than 10µs
PRIM_RX = 1
CE = 1
CE = 0
TX FIFO empty
CE = 1
TX FIFO not empty
CE = 1
PRIM_RX = 0
TX FIFO empty
CE = 1
PWR_UP = 0
PWR_UP = 0
PWR_UP=0
CE = 0
PWR_UP=0
PWR_UP=0
TX finished with one packet
CE = 0
CE = 1
TX FIFO not empty
Possible operating mode
Recommended path between operating modes
Possible path between operating modes
Recommended operating mode
Transition state
CE = 1
Pin signal condition
PWR_DN = 1
Bit state condition
Undefined
TX FIFO empty
System information
Undefined
Legend: