STM32WLE4JC datasheet(97/145 Pages) STMICROELECTRONICS

97 / 145 page

DS13105 Rev 8

97/145

STM32WLE5/E4xx

Electrical characteristics

133

the resonator and the load capacitors have to be placed as close as possible to the

oscillator pins to minimize output distortion and startup stabilization time.

Refer to the crystal resonator manufacturer for more details on the resonator characteristics

(frequency, package, accuracy).

For more information on the crystal selection, refer to application note Oscillator design

guide for STM8AF/AL/S, STM32 MCUs and MPUs (AN2867).

Figure 16. Typical application with a 32.768 kHz crystal

Note:

No external resistors are required between OSC32_IN and OSC32_OUT, and it is forbidden

to add one.

In bypass mode, the LSE oscillator is switched off and the input pin is a standard GPIO.

Table 59. Low-speed external user clock characteristics(1)

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

IDD(LSE)

LSE current

consumption

LSEDRV[1:0] = 00 - Low drive capability

250

LSEDRV[1:0] = 01 - Medium-low drive capability

315

LSEDRV[1:0] = 10 - Medium-high drive capability

500

LSEDRV[1:0] = 11 - High drive capability

630

Gmcritmax

Maximum

critical crystal

LSEDRV[1:0] = 00 - Low drive capability

0.50

µA/V

LSEDRV[1:0] = 01 - Medium-low drive capability

0.75

LSEDRV[1:0] = 10 - Medium-high drive capability

1.70

LSEDRV[1:0] = 11 - High drive capability

2.70

tSU(LSE)(2) Startup time

VDD stabilized

1. Guaranteed by design.

2. tSU(LSE) is the startup time measured from the moment it is enabled (by software) until a stable 32.768 kHz oscillation is

reached. This value is measured for a standard crystal and it can vary significantly with the crystal manufacturer.

MS30253V2

OSC32_IN

OSC32_OUT

Drive

programmable

amplifier

fLSE

32.768 kHz

resonator

Resonator with integrated

capacitors

CL1

CL2

STM32WLE4JC 数据表(PDF) 97 Page - STMicroelectronics

STM32WLE4JC 数据表(HTML) 97 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载