Datasheet

MSP430F532x
www.ti.com SLAS678D –AUGUST 2010–REVISED FEBRUARY 2013
Crystal Oscillator, XT2
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)
(1) (2)
PARAMETER TEST CONDITIONS V
CC
MIN TYP MAX UNIT
f
OSC
= 4 MHz, XT2OFF = 0,
XT2BYPASS = 0, XT2DRIVEx = 0, 200
T
A
= 25°C
f
OSC
= 12 MHz, XT2OFF = 0,
XT2BYPASS = 0, XT2DRIVEx = 1, 260
T
A
= 25°C
XT2 oscillator crystal current
I
DVCC.XT2
3 V µA
consumption
f
OSC
= 20 MHz, XT2OFF = 0,
XT2BYPASS = 0, XT2DRIVEx = 2, 325
T
A
= 25°C
f
OSC
= 32 MHz, XT2OFF = 0,
XT2BYPASS = 0, XT2DRIVEx = 3, 450
T
A
= 25°C
XT2 oscillator crystal frequency,
f
XT2,HF0
XT2DRIVEx = 0, XT2BYPASS = 0
(3)
4 8 MHz
mode 0
XT2 oscillator crystal frequency,
f
XT2,HF1
XT2DRIVEx = 1, XT2BYPASS = 0
(3)
8 16 MHz
mode 1
XT2 oscillator crystal frequency,
f
XT2,HF2
XT2DRIVEx = 2, XT2BYPASS = 0
(3)
16 24 MHz
mode 2
XT2 oscillator crystal frequency,
f
XT2,HF3
XT2DRIVEx = 3, XT2BYPASS = 0
(3)
24 32 MHz
mode 3
XT2 oscillator logic-level square-
f
XT2,HF,SW
wave input frequency, bypass XT2BYPASS = 1
(4) (3)
0.7 32 MHz
mode
XT2DRIVEx = 0, XT2BYPASS = 0,
450
f
XT2,HF0
= 6 MHz, C
L,eff
= 15 pF
XT2DRIVEx = 1, XT2BYPASS = 0,
320
f
XT2,HF1
= 12 MHz, C
L,eff
= 15 pF
Oscillation allowance for
OA
HF
Ω
HF crystals
(5)
XT2DRIVEx = 2, XT2BYPASS = 0,
200
f
XT2,HF2
= 20 MHz, C
L,eff
= 15 pF
XT2DRIVEx = 3, XT2BYPASS = 0,
200
f
XT2,HF3
= 32 MHz, C
L,eff
= 15 pF
f
OSC
= 6 MHz,
XT2BYPASS = 0, XT2DRIVEx = 0, 0.5
T
A
= 25°C, C
L,eff
= 15 pF
t
START,HF
Startup time 3 V ms
f
OSC
= 20 MHz,
XT2BYPASS = 0, XT2DRIVEx = 2, 0.3
T
A
= 25°C, C
L,eff
= 15 pF
Integrated effective load
C
L,eff
1 pF
capacitance, HF mode
(6) (1)
Duty cycle, HF mode Measured at ACLK, f
XT2,HF2
= 20 MHz 40 50 60 %
(1) Requires external capacitors at both terminals. Values are specified by crystal manufacturers. In general, an effective load capacitance
of up to 18 pF can be supported.
(2) To improve EMI on the XT2 oscillator the following guidelines should be observed.
(a) Keep the traces between the device and the crystal as short as possible.
(b) Design a good ground plane around the oscillator pins.
(c) Prevent crosstalk from other clock or data lines into oscillator pins XT2IN and XT2OUT.
(d) Avoid running PCB traces underneath or adjacent to the XT2IN and XT2OUT pins.
(e) Use assembly materials and praxis to avoid any parasitic load on the oscillator XT2IN and XT2OUT pins.
(f) If conformal coating is used, ensure that it does not induce capacitive/resistive leakage between the oscillator pins.
(3) This represents the maximum frequency that can be input to the device externally. Maximum frequency achievable on the device
operation is based on the frequencies present on ACLK, MCLK, and SMCLK cannot be exceed for a given range of operation.
(4) When XT2BYPASS is set, the XT2 circuit is automatically powered down. Input signal is a digital square wave with parametrics defined
in the Schmitt-trigger Inputs section of this datasheet.
(5) Oscillation allowance is based on a safety factor of 5 for recommended crystals.
(6) Includes parasitic bond and package capacitance (approximately 2 pF per pin).
Since the PCB adds additional capacitance, it is recommended to verify the correct load by measuring the ACLK frequency. For a
correct setup, the effective load capacitance should always match the specification of the used crystal.
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