EFM32WG840F128 Energy Micro, EFM32WG840F128 Datasheet - Page 23

• Manufacturer Part Number: EFM32WG840F128
• Description: ARM Microcontrollers - MCU 128kb flash 32kb RAM
• Manufacturer: Energy Micro

Specifications of EFM32WG840F128

• Rohs: yes
• Core: ARM Cortex M4F
• Processor Series: EFM32WG840
• Data Bus Width: 32 bit
• Maximum Clock Frequency: 48 MHz
• Program Memory Size: 128 KB
• Data Ram Size: 32 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 1.85 V to 3.8 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: QFN-64
• Mounting Style: SMD/SMT

3.9.2 HFXO
3.9.3 LFRCO
2012-09-11 - EFM32WG840FXX - d0195_Rev1.00
Table 3.10. Minimum Load Capacitance (C
Table 3.11. HFXO
Table 3.12. LFRCO
Shunt Capacitance C
CL
redlfxoboost = 1
CL
redlfxoboost = 0
CL
redlfxoboost = 1
CL
redlfxoboost = 0
Symbol
f
ESR
g
C
DC
I
t
Symbol
f
t
I
TUNESTEP
FRCO
HFXO
HFXO
HFXO
LFRCO
LFRCO
LFRCO
mHFXO
HFXOL
min
min
min
min
HFXO
HFXO
lfxoboost = 0
lfxoboost = 1
lfxoboost = 1
lfxoboost = 1
Symbol
L-
Parameter
Supported nominal crystal
Frequency
Supported crystal equiv-
alent series resistance
(ESR)
The transconductance of
the HFXO input transistor
at crystal startup
Supported crystal external
load range
Duty cycle
Current consumption for
HFXO after startup
Startup time
Parameter
Oscillation frequency ,
V
Startup time not including
software calibration
Current consumption
Frequency step for LSB
change in TUNING value
DD
= 3.0 V, T
0
0.5
3.7
7.3
10.0 10.6 11.1 11.6 12.1 12.6 13.0 13.4 13.8 14.1 14.5 14.8 15.1 15.4 15.7 16.0
12.5 13.2 13.9 14.5 15.0 15.5 16.0 16.5 16.9 17.4 17.8 18.2 18.5 18.9 19.3 19.6
AMB
0.6
4.0
7.7
=25°C
Preliminary
0.7
4.3
8.2
0.8
4.5
8.6
Condition
Crystal frequency 32 MHz
Crystal frequency 4 MHz
HFXOBOOST in CMU_CTRL
equals 0b11
4 MHz: ESR=400 Ohm,
C
CMU_CTRL equals 0b11
32 MHz: ESR=30 Ohm,
C
CMU_CTRL equals 0b11
32 MHz: ESR=30 Ohm,
C
CMU_CTRL equals 0b11
Condition
L
L
L
=20 pF, HFXOBOOST in
=10 pF, HFXOBOOST in
=10 pF, HFXOBOOST in
0.9
4.8
9.0
LFXOL
1.0
5.0
9.3
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23
) Requirement For Safe Crystal Startup
1.1
5.3
9.6
Capacitance [pF]
1.2
5.5
10.0 10.3 10.5 10.8 11.1 11.3 11.6 11.8 12.1
1.3
5.7
Min
Min
1.4
5.9
20
46
1.5
6.0
4
5
Typ
Typ
32.768
1.6
6.2
www.energymicro.com
400
165
400
150
190
1.5
30
50
85
1.7
6.4
Max
Max
1.8
6.5
1500 Ohm
48 MHz
60 Ohm
25 pF
54 %
1.9
6.7
Unit
mS
µA
µA
µs
Unit
kHz
µs
nA
%
2.0
6.9