Datasheet

MSP430x461x1, MSP430x461x
MIXED SIGNAL MICROCONTROLLER
46
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics over recommended operating free-air temperature (unless otherwise
noted)
crystal oscillator, LFXT1 oscillator (see Notes 1 and 2)
PARAMETER TEST CONDITIONS V
CC
MIN TYP MAX UNIT
OSCCAPx = 0h 2.2 V / 3 V 0
C
Integrated input capacitance (see Note 4)
OSCCAPx = 1h 2.2 V / 3 V 10
pF
C
XIN
Integrated input capacitance (see Note 4)
OSCCAPx = 2h
2.2 V / 3 V 14
pF
OSCCAPx = 3h 2.2 V / 3 V 18
OSCCAPx = 0h 2.2 V / 3 V 0
C
Integrated output capacitance (see Note 4)
OSCCAPx = 1h 2.2 V / 3 V 10
pF
C
XOUT
Integrated output capacitance (see Note 4)
OSCCAPx = 2h
2.2 V / 3 V 14
pF
OSCCAPx = 3h 2.2 V / 3 V 18
V
IL
Input levels at XIN
See Note 3
2 2 V/3 V
V
SS
0.2×V
CC
V
V
IH
Input levels at XIN See Note 3 2.2 V/3 V
0.8×V
CC
V
CC
V
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
(C
XIN
xC
XOUT
) / (C
XIN
+ C
XOUT
). This is independent of XTS_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 the trace between the MSP430 device and the crystal as short as possible.
− 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.
3. Applies only when using an external logic-level clock source. XTS_FLL must be set. Not applicable when using a crystal or resonator.
4. External capacitance is recommended for precision real-time clock applications; OSCCAPx = 0h.
crystal oscillator, XT2 oscillator (see Note 1)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
C
XT2IN
Integrated input capacitance V
CC
= 2.2 V/3 V 2 pF
C
XT2OUT
Integrated output capacitance V
CC
= 2.2 V/3 V 2 pF
V
IL
Input levels at XT2IN
V
CC
= 2 2 V/3 V (see Note 2)
V
SS
0.2 × V
CC
V
V
IH
Input levels at XT2IN V
CC
= 2.2 V/3 V (see Note 2)
0.8 × V
CC
V
CC
V
NOTES: 1. The oscillator needs capacitors at both terminals, with values specified by the crystal manufacturer.
2. Applies only when using an external logic-level clock source. Not applicable when using a crystal or resonator.