Datasheet

Page 20 of 161
nRF8001 Product Specification
Revision 1.2
6.4 Temperature sensor
nRF8001 incorporates an integrated temperature sensor. The temperature sensor reports the silicon
temperature. The temperature sensor’s electrical specifications are defined in Chapter 12 on page 34
.
6.4.1 Enabling the temperature sensor
The temperature sensor is enabled through the ACI protocol, see Part B, section 24 on page 96. When
nRF8001 receives an ACI command initiating the temperature reading it will enable the temperature
sensor and start the internal measurement procedure. Upon completion, nRF8001 returns an ACI event
reporting the current temperature reading.
6.5 Battery monitor
nRF8001 incorporates an integrated battery monitor. The battery monitor reports the supply voltage (VDD)
connected to nRF8001 supply pins. The battery monitor’s electrical specifications are defined in Chapter
12 on page 34.
6.5.1 Enabling the battery monitor
The battery monitor sensor is enabled through the ACI protocol see Part B, section 24 on page 96. When
nRF8001 receives an ACI command initiating the battery reading it will enable the battery monitor and start
the internal measurement procedure. Upon completion, the nRF8001 returns an ACI event reporting the
current battery monitor reading.
6.6 Dynamic Window Limiting
Dynamic Window Limiting reduces the average current consumption by reducing the window widening of
the receiver, see Bluetooth Core specification v4.0, Vol. 6, Part B, section 4.5.7. Dynamic Window Limiting
is an optional feature that can be enabled or disabled using nRFgo Studio (see section 22.3 on page 81
for
more information on nRFgo Studio). Enabling this feature reduces the overall system ppm to an average of
20 ppm.
Note: Under conditions that cause a major disruption to either the local or peer low frequency clock,
the connection may become unstable and terminate.
6.7 Application latency
Application Latency is an optional feature that subrates the slave latency so that nRF8001 listens for the
central device’s packets at the subrated connection interval. When nRF8001 is in a connection, Application
Latency can be enabled or disabled in real time (see Part B, section 24.23 on page 128
). When it is
enabled, it is used with Slave Latency, see Bluetooth Core specification v4.0, Vol. 6, Part B, section 4.5.1.
When Application Latency is enabled, nRF8001 does not turn on its transmitter and acknowledge an
empty received packet. This saves nRF8001 current by returning to a low current mode, it also reduces the
application latency between a central device and a peripheral device. If the received packet is empty but
the MD (More Data) bit in the header is set to 1 then nRF8001 acknowledges the empty packet and listens
in the same event for the data indicated by the MD bit.
The average current consumption of the link is significantly reduced compared to a regular continuous
connection. But, the application latency of data both for the central and peripheral is significantly lower
than for a connection using slave latency only.