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Monitor mode
In the previous sections, three different
levels of power saving options were
discussed. To achieve the best power
saving in a system, reducing the power
consumption for only the ADRV9001 might
not be sufficient. Ideally, during the long
idle time period, the best power saving
of the entire system is achieved when all
the major components can be powered
down. To achieve this goal, a monitor
mode is provided that allows both the
Figure 8: An example of using combined channel-level and system-level power saving. ADRV9001 and the BBIC to go into deep
sleep during the entire idle time period—
Table 5: Power Consumption During Different Time Periods of a TDD DMR Profile Using except for one receive channel, which
Channel-Level Power Saving Mode 2 and System-Level Power Saving Modes 3, 4, and 5 could optionally wake up to perform signal
detection periodically. When a valid signal
System-Level Power Consumption (mW)
Power Saving Mode is found, the ADRV9001 wakes up the
(For Idle Only) P TX (Transmit Only, P RX (Receive Only, P IDLE (Idle) BBIC immediately. This offloads the signal
Mode 2) Mode 2) detection responsibility from the BBIC
and allows it (and possibly other circuitry
Mode 3 580 502 100
in the system controlled by the BBIC) to
Mode 4 580 502 65 sleep during the entire idle time period to
achieve the highest overall system power
Mode 5 580 502 35 saving.
Figure 9 shows a simplified state
diagram of the ADRV9001 and how it
power saving can only be employed when both TX_ENABLE and RX_ENABLE signals are low. transitions between normal operation
Table 5 presents the power consumption for the DMR use case shown in figure 7 by mode and monitor mode.
using power saving mode 2 when one channel is active, and three different system-level As shown in figure 9, with normal
power saving modes when both channels are idle. operation mode, after the ADRV9001 is
Compared with Table 3, during the idle time period, it is clear that using the system-level powered up, it automatically goes to the
power saving modes can save more power. For the same 5-5-90 DMR use case, the average standby state, during which the user can
power consumption using mode 5 is further lowered, which can be calculated as 580 × 5% + configure component-level power saving
502 × 5% + 35 × 90% = 86 mW. options. The standby state will switch to
the calibrated state if the initialisation
is successful. As mentioned earlier, in
this state, unused channels (although
initialised) can be powered down using an
API command to move from the calibrate
ready substate to hibernate substate.
From the calibrated state, the radio on
command further primes the channels
to prepare for transmit and receive
operations and all channels are switched
to the primed ready substate. Note: this
substate is equivalent to the default
channel-level power saving mode 0. When
channel enable signal is on, channels are
further moved to RF_ON state to start
operation. As discussed earlier, during
a TDD operation, idle channels can be
powered down using channel-level power
saving modes. If using power saving mode
Figure 9: State diagram of the ADRV9001 in normal operation mode and monitor mode. 0, it moves the idle channel from RF_ON

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