Sym

Parameter (1) (2)

Min.

Typ.

Max.

Units

Resonant frequency

-

32.768

kHz

-

75 (3) (4)

kΩ

Load capacitance

-

6

pF

1. Load capacitors are integrated within the M41T6x. Circuit board layout considerations for the 32.768 kHz

crystal of minimum trace lengths and isolation from RF generating signals should be taken into account.

2. For the QFN16 package, user-supplied external crystals are required. The 6 and 7 pF crystals listed in

Table 15. Crystals suitable for use with M41T6x series RTCs have been evaluated by ST and have been

found to be satisfactory for use with the M41T6x series RTC.

4. Guaranteed by design.

Vendor

Order number

Package

Manufacturer’s specifications

ESR

max.

Temp. range

(°C)

Rated

tolerance at

25 °C

Rated load

cap.

Citizen

CMJ206T-32.768KDZB-UB

8.3 x 2.5 mm leaded SMT

50 kΩ

–40/+85

±20 ppm

6 pF

Citizen

CM315-32.768KDZY-UB

3.2 x 1.5 x 0.9 mm SMT

70 kΩ

–40/+85

±20 ppm

7 pF

Ecliptek

E4WCDA06-32.768K (1)

2.0 x 6.0 mm thru-hole

50 kΩ

–10/+60

±20 ppm

6 pF

Ecliptek

E5WSDC 07 - 32.768K

7 x 1.5 x 1.4 mm SMT

65 kΩ

–40/+85

±20 ppm

7 pF

ECS

ECS-.327-6-17X-TR

3.8 x 8.5 x 2.5 mm SMT

50 kΩ

–40/+85

±20 ppm

6 pF

ECS

ECS-.327-7-34B-TR

3.2 x 1.5 x 0.9 mm SMT

70 kΩ

–40/+85

±20 ppm

7 pF

ECS

ECS-.327-7-38-TR

7 x 1.5 x 1.4 mm SMT

65 kΩ

–40/+85

±20 ppm

7 pF

Epson

MC-146 32.7680KA-AG: ROHS (2)

7 x 1.5 x 1.4 mm SMT

65 kΩ

–40/+85

±20 ppm

7 pF

Fox

298LF-0.032768-19

1.5 x 5.0 mm thru-hole

50 kΩ

–20/+60

±20 ppm

6 pF

Fox

299LF-0.032768-37

2.0 x 6.0 mm thru-hole

50 kΩ

–20/+60

±20 ppm

6 pF

Fox

414LF-0.032768-12

3.8 x 8.5 x 2.5 mm SMT

50 kΩ

–40/+85

±20 ppm

6 pF

Fox

501LF-0.032768-5

7 x 1.5 x 1.4 mm SMT

65 kΩ

–40/+85

±20 ppm

7 pF

Micro

Crystal

MS3V-T1R 32.768KHZ 7PF 20PPM

6.7 x 1.4 mm

leaded SMT

65 kΩ

–40/+85

±20 ppm

7 pF

Pletronics

SM20S - 32.768K - 6pF

3.8 x 8.5 x 2.5 mm SMT

50 kΩ

–40/+85

±20 ppm

6 pF

Seiko

SSPT7F-7PF20PPM

7 x 1.5 x 1.4 mm SMT

65 kΩ

–40/+85

±20 ppm

7 pF

Seiko

VT200F-6PF20PPM

2.0 x 6.0 mm thru-hole

50 kΩ

–10/+60

±20 ppm

6 pF

1. ST has been informed that this crystal has been terminated by the vendor.

2. Epson MC-146 32.7680KA-E: ROHS is 6 pF version.

Sym

Parameter

Conditions

Min.

Typ.

Max.

Unit

Oscillator start voltage

≤ 10 seconds

1.5

V

Oscillator start time

1

s

XIN capacitance

12

pF

M41T62, M41T64, M41T65

DC and AC parameters

DS3840 - Rev 24

page 25/42