MSP432P401R Datasheet, PDF (29/157 Pages) Texas Instruments – Mixed-Signal Microcontrollers

www.ti.com
MSP432P401R, MSP432P401M
SLAS826B – MARCH 2015 – REVISED FEBRUARY 2016
Table 5-18. Low-Frequency Crystal Oscillator, LFXT
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)
I_VCC,LFXT
f_LFXT
DC_LFXT
f_LFXT,SW
PARAMETER
TEST CONDITIONS
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {0},
C_L,eff = 3.7 pF
Typical ESR, C_SHUNT
Current consumption⁽¹⁾
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {1},
C_L,eff = 6 pF
Typical ESR, C_SHUNT
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {2},
C_L,eff = 9 pF,
Typical ESR, C_SHUNT
LFXT oscillator crystal frequency
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {3},
C_L,eff = 12 pF,
Typical ESR, C_SHUNT
LFXTBYPASS = 0⁽²⁾
LFXT oscillator duty cycle
f_LFXT = 32.768 kHz⁽²⁾
LFXT oscillator logic-level square-
wave input frequency
LFXTBYPASS = 1^{(3) (4)}
V_CC
3.0 V
3.0 V
3.0 V
3.0 V
MIN TYP MAX UNIT
100
200
300
nA
500
32.768
30%
10 32.768
kHz
70%
50 kHz
DC_LFXT,
SW
OA_LFXT
C_L,eff
LFXT oscillator logic-level square-
wave input duty cycle
LFXTBYPASS = 1
Oscillation allowance for
LF crystals⁽⁵⁾
Integrated effective load
capacitance^{(6) (7)}
LFXTBYPASS = 0, LFXTDRIVE =
{1},
f_LFXT = 32.768 kHz, C_L,eff = 6 pF
LFXTBYPASS = 0, LFXTDRIVE =
{3},
f_LFXT = 32.768 kHz, C_L,eff = 12 pF
30%
70%
TBD
kΩ
300
1
pF
t_START,LFXT Start-up time⁽⁸⁾
f_Fault,LFXT Oscillator fault frequency^{(9) (10)}
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {0},
C_L,eff = 3.7 pF
Typical ESR, C_SHUNT
FCNTLF_EN = 0⁽²⁾
f_OSC = 32.768 kHz
LFXTBYPASS = 0, LFXTDRIVE = {3},
C_L,eff = 12 pF
Typical ESR, C_SHUNT
FCNTLF_EN = 0⁽²⁾
3.0 V
0.6
s
2
1
8 kHz
(1) Total current measured on both AVCC and DVCC supplies.
(2) Measured at ACLK pin.
(3) When LFXTBYPASS is set, LFXT circuits are automatically powered down. Input signal is a digital square wave with parametrics
defined in the Schmitt-trigger Inputs section of this datasheet. Duty cycle requirements are defined by DC_{LFXT, SW}.
(4) Maximum frequency of operation of the entire device cannot be exceeded.
(5) Oscillation allowance is based on a safety factor of 5 for recommended crystals. The oscillation allowance is a function of the
LFXTDRIVE settings and the effective load. In general, comparable oscillator allowance can be achieved based on the following
guidelines, but should be evaluated based on the actual crystal selected for the application:
• For LFXTDRIVE = {0}, C_L,eff = 3.7 pF.
• For LFXTDRIVE = {1}, 6 pF ≤ C_L,eff ≤ 9 pF.
• For LFXTDRIVE = {2}, 6 pF ≤ C_L,eff ≤ 10 pF.
• For LFXTDRIVE = {3}, 6 pF ≤ C_L,eff ≤ 12 pF.
(6) Includes parasitic bond and package capacitance (approximately 2 pF per pin).
(7) Requires external capacitors at both terminals. Values are specified by crystal manufacturers. Recommended values supported are
3.7 pF, 6 pF, 9 pF, and 12 pF. Maximum shunt capacitance of 1.6 pF. Because the PCB adds additional capacitance, it must be
considered, and TI recommends verifying proper oscillator performance.
(8) Does not include programmable startup counter.
(9) Frequencies above the MAX specification do not set the fault flag. Frequencies in between the MIN and MAX specification may set the
flag. A static condition or stuck at fault condition will set the fault flag.
(10) Measured with logic-level input frequency but also applies to operation with crystals.
Copyright © 2015–2016, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: MSP432P401R MSP432P401M
Specifications
29