MSP430X43X Datasheet, PDF (39/64 Pages) Texas Instruments – Mixed signal microcontroller

MSP430x43x, MSP430x44x
MIXED SIGNAL MICROCONTROLLER
SLAS344B – JANUARY 2002 – REVISED OCTOBER 2002
Legend
Tolerance at Tap 27
DCO Frequency
Adjusted by Bits
29 to 2 ⁵ in SCFI1 {N _(DCO)}
Tolerance at Tap 2
Overlapping DCO Ranges:
uninterrupted frequency range
FN_2=0
FN_3=0
FN_4=0
FN_8=0
FN_2=1
FN_3=0
FN_4=0
FN_8=0
FN_2=x
FN_3=1
FN_4=0
FN_8=0
FN_2=x
FN_3=x
FN_4=1
FN_8=0
FN_2=x
FN_3=x
FN_4=x
FN_8=1
Figure 16. Five Overlapping DCO Ranges Controlled by FN_x Bits
electrical characteristics over recommended operating free-air temperature (unless otherwise
noted)
crystal oscillator, LFXT1 oscillator (see Notes 1 and 2)
PARAMETER
TEST CONDITIONS
MIN TYP MAX UNIT
OSCCAP = 0, VCC = 2.2 V / 3 V
0
C(XIN)
Integrated input capacitance
OSCCAP = 1, VCC = 2.2 V / 3 V
OSCCAP = 2, VCC = 2.2 V / 3 V
10
pF
14
OSCCAP = 3, VCC = 2.2 V / 3 V
18
OSCCAP = 0, VCC = 2.2 V / 3 V
0
C(XOUT)
Integrated output capacitance
OSCCAP = 1, VCC = 2.2 V / 3 V
OSCCAP = 2, VCC = 2.2 V / 3 V
10
pF
14
OSCCAP = 3, VCC = 2.2 V / 3 V
18
NOTES: 1. The parasitic capacitance from the package and board may be estimated to be 2 pF. The effective load capacitor for the crystal is
(X(CIN) x X(COUT)) / (X(CIN) + X(COUT)). This is independent of XST_FLL.
2. To improve EMI on the low-power LFXT1 oscillator, particularly in the LF mode (32 kHz), the following guidelines should be observed.
– Keep as short of a trace as possible between the F43x/44x and the crystal.
– Design a good ground plane around the oscillator pins.
– Prevent crosstalk from other clock or data lines into oscillator pins XIN and XOUT.
– Avoid running PCB traces underneath or adjacent to the XIN and XOUT pins.
– Use assembly materials and praxis to avoid any parasitic load on the oscillator XIN and XOUT pins.
– If conformal coating is used, ensure that it does not induce capacitive/resistive leakage between the oscillator pins.
– Do not route the XOUT line to the JTAG header to support the serial programming adapter as shown in other
documentation. This signal is no longer required for the serial programming adapter.
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