MC68HC908KX8 Datasheet, PDF (307/310 Pages) Motorola, Inc – Microcontrollers

MC68HC08KX8 Overview
Electrical Specifiations
B.5.8 Trimmed Accuracy of the Internal Clock Generator
The unadjusted frequency of the low-frequency base clock (IBASE),
when the comparators in the frequency comparator indicate zero error,
can vary as much as ±25% due to process, temperature, and voltage.
The trimming capability exists to compensate for process affects. The
remaining variation in frequency is due to temperature, voltage, and
change in target frequency (multiply register setting). These affects are
designed to be minimal, however variation does occur. Better
performance is seen at 3 V and lower settings of N.
B.5.8.1 2.7-Volt to 3.3-Volt Trimmed Internal Clock Generator Characteristics
Characteristic⁽¹⁾
Symbol
Min
Absolute trimmed internal oscillator tolerance^{(2), (3)}
–40°C to 85°C
F_{abs_tol}
—
Variation over temperature^{(3), (4)}
V_{ar_temp}
—
Variation over voltage^{(3), (5)}
25°C
–40°C to 85°C
V_{ar_volt}
—
—
Typ
1.5
0.03
0.5
0.7
Max
5.0
0.05
2.0
2.0
Unit
%
%/C
%/V
1. These specifications concern long-term frequency variation. Each measurement is taken over a 1-ms period.
2. Absolute value of variation in ICG output frequency, trimmed at nominal V_DD and temperature, as temperature and V_DD
are allowed to vary for a single given setting of N.
3. Specification is characterized but not tested.
4. Variation in ICG output frequency for a fixed N and voltage
5. Variation in ICG output frequency for a fixed N
B.5.8.2 4.5-Volt to 5.5-Volt Trimmed Internal Clock Generator Characteristics
Characteristic⁽¹⁾
Symbol
Min
Absolute trimmed internal oscillator tolerance^{(2), (3)}
–40°C to 85°C
F_{abs_tol}
—
Variation over temperature^{(3), (4)}
V_{ar_temp}
—
Variation over voltage^{(3), (5)}
25°C
–40°C to 85°C
V_{ar_volt}
—
—
Typ
4.0
0.05
1.0
1.0
Max
7.0
0.08
2.0
2.0
Unit
%
%/C
%/V
1. These specifications concern long-term frequency variation. Each measurement is taken over a 1-ms period.
2. Absolute value of variation in ICG output frequency, trimmed at nominal V_DD and temperature, as temperature and V_DD
are allowed to vary for a single given setting of N.
3. Specification is characterized but not tested.
4. Variation in ICG output frequency for a fixed N and voltage
5. Variation in ICG output frequency for a fixed N
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 — Rev. 1.0
MOTOROLA
MC68HC08KX8 Overview
Technical Data
307