EM2420-STR Ember, EM2420-STR Datasheet - Page 50

• Manufacturer Part Number: EM2420-STR
• Description: IC RF TXRX ZIGBEE 2.4GHZ 48-QLP
• Manufacturer: Ember

Specifications of EM2420-STR

• Mfg Application Notes: EM2420
• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: ZigBee™
• Power - Output: -3dBm
• Sensitivity: -94dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 19.7mA
• Current - Transmitting: 17.4mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-QLP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Memory Size: -

The battery monitor is controlled through
the BATTMON control register. The battery
monitor is enabled and disabled using the
BATTMON.BATTMON_EN control bit. The
voltage regulator must also be enabled
when using the battery monitor.
The battery monitor status bit is available
in the BATTMON.BATTMON_OK status bit.
This bit is high when the VREG_IN input
voltage is higher than the toggle voltage
V
The battery monitor toggle voltage is set in
the 5-bit BATTMON.BATTMON_VOLTAGE
control bits. BATTMON_VOLTAGE is an
unsigned, positive number from 0 to 31.
The toggle voltage is given by:
Crystal Oscillator
An external clock signal or the internal
crystal oscillator can be used as the main
frequency
frequency must be 16 MHz. Because the
crystal frequency is used as reference for
the data rate as well as other internal
signal
frequencies cannot be used.
V
Ember Part Number: 120-0049-000D
toggle
toggle
.
=
. 1
25
BATTMON.BATTMON_EN
processing
V
⋅
72
reference.
−
BATTMON_VO
reference
Figure 27. Battery monitor, simplified schematic
27
bandgap
Internal
voltage
functions,
The
LTAGE
1.25 V
reference
other
EM2420 Datasheet
VREG_IN
Alternatively, for a desired toggle voltage,
BATTMON_VOLTAGE
according to:
The voltage regulator must be enabled for
at
measurement. After being enabled, the
BATTMON_OK status bit needs 2 µs to
settle
programmed.
The main performance characteristics of
the battery monitor are shown in the
Electrical Specifications section on page
8.
If an external clock signal is used this
should be connected to XOSC16_Q1, while
XOSC16_Q2 should be left open. The
MAIN.XOSC16M_BYPASS bit must be set
when an external clock signal is used.
Using the internal crystal oscillator, the
crystal must be connected between the
XOSC16_Q1 and XOSC16_Q2 pins. The
oscillator is designed for parallel mode
BATTMON_VO
least
BATTMON.BATTMON_VOLTAGE[4:0]
BATTMON.BATTMON_OK
for
LTAGE
100
each
=
72
µs
new
−
27
should
before
EM2420
⋅
. 1
V
25
toggle
toggle
V
Page 50 of 84
the
be
voltage
first
set