TC39x BC/BD-Step
Electrical SpecificationMHz Oscillator
3.9
MHz Oscillator
OSC_XTAL is used as accurate and exact clock source. OSC_XTAL supports 16 MHz to 40 MHz crystals external
outside of the device. Support of ceramic resonators is also provided.
Table 3-23 OSC_XTAL
Parameter
Symbol
Values
Typ.
Unit
Note / Test Condition
Min.
-70
4
Max.
70
Input current at XTAL1
Oscillator frequency
I
IX1 CC
-
-
µA
VIN>0V ; VIN<VEXT
f
OSC SR
40
MHz
Direct Input Mode
selected, if shaper is
not bypassed
16
-
-
-
-
40
MHz
ms
External Crystal Mode
selected
Oscillator start-up time
t
OSCS CC
-
3 1)
20MHz ≤ fOSC and 8pF
load capacitance
Input voltage at XTAL1 2)
VIX SR
PPX SR
-0.7
V
EXT + 0.5 V
EXT + 1.0 V
If shaper is not
bypassed
Input amplitude (peak to peak)
at XTAL1
V
0.3*VEXT
V
If shaper is not
bypassed; fOSC
25MHz
>
≤
0.35*VEXT
-
VEXT + 1.0 V
If shaper is not
bypassed; fOSC
25MHz
Internal load capacitor
Internal load capacitor
Internal load capacitor
Internal load capacitor
C
C
C
C
C
C
L0 CC
1.30
3.05
7.85
12.05
1.15
-
1.40
3.35
8.70
13.35
1.20
2.5
1.55
3.70
9.55
14.65
1.25
4
pF
pF
pF
pF
pF
pF
enabled via bit
OSCCON.CAP0EN
L1 CC
enabled via bit
OSCCON.CAP1EN
L2 CC
enabled via bit
OSCCON.CAP2EN
L3 CC
enabled via bit
OSCCON.CAP3EN
Internal load stray capacitor
between XTAL1 and XTAL2
XINTS CC
XTAL1 CC
Internal load stray capacitor
between XTAL1 and ground
Duty cycle at XTAL1 3)
Absolute RMS jitter at XTAL1 3)
Slew rate at XTAL1 3)
DCX1 SR
ABSX1 SR
35
-
-
-
-
65
28
-
%
VXTAL1 = 0.5*VPPX
J
ps
10 KHz to fOSC/2
SRXTAL1 SR 0.3
V/ns
Maximum 30%
difference between
rising and falling slew
rate
1) tOSCS is defined from the moment when the Oscillator Mode is set to External Crystal Mode until the oscillations reach an
amplitude at XTAL1 of 0.3 * VEXT.
This value depends on the frequency of the used external crystal. For faster crystal frequencies this value decrease.
2) For Supply (VEXT < 5.3V VIX) min could be down to -0.9V. For XTAL1 an input level down to -0.9V will not cause a damage or
a reliability problem operating with an external crystal.
Data Sheet
442
V 1.2, 2021-03
OPEN MARKET VERSION
INFINEON [ Infineon ]
