XE88LC05MI000 ETC1 [List of Unclassifed Manufacturers], XE88LC05MI000 Datasheet - Page 16

• Manufacturer Part Number: XE88LC05MI000
• Description: 16 + 10 bit Data Acquisition Ultra Low-Power Microcontroller
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

Data Acquisition Microcontroller
XE88LC05
Table 7.1:
Note:
7.6 RC oscillator
Note:
Table 7.2:
duty_clk32k
Figure 7.1:
16
symbol
symbol
f_clk32k
st_x32k
range
fstab_1
F
st
relative frequency deviation from
duty cycle on the digital output
CL=8.2 pF and temperature
frequency at start-up
nominal, for a crystal with
between -40° and +85°C
oscillator start-up time
range selection
description
nominal frequency
description
Xtal oscillator specifications.
Board layout recommendations for safer crystal oscillation and lower current consumption:
Keep lines xtal_in and xtal_out short and insert a VSS line between them.
Connect package of the crystal to VSS.
No noisy or digital lines near xtal_in and xtal_out.
Insert guards at VSS where needed.
The RC Oscillator is always turned on at power-on reset and can be turned off after the option-
al Xtal oscillator has been started. The RC oscillator has two frequency ranges: sub-MHz
(100KHz to 1MHz) and above-MHz (1MHz to max MCU frequency). Inside a range, the fre-
quency can be tuned by software for coarse and fine adjustment.
No external component is required for the RC oscillator.
The RC oscillator can be in 3 modes. In mode 1(RC on), the RC oscillator and its bias are on.
In mode 2 (RC ready), the RC oscillator is off and the bias is on. In mode 3 (RC off), the RC
oscillator and the bias are off. RC ready mode is a compromise between power consumption
and start-up time.
RC specifications
RC frequencies programming example for low range (typical values)
min
50
1
-100
min
30
typ
80
32768
typ
50
1
max
110
10
+300
max
70
2
unit
kHz
ppm
unit
Hz
%
s
not included:
crystal frequency tolerance and aging
crystal frequency - temperature dependence
multiplies F
comments
for full precision
at 27°C
comments
st
D0109-40