M48T37Y, M48T37V

Clock operations

Doc ID 7019 Rev 9

19/30

one volt. These negative spikes can cause data corruption in the SRAM while in battery

backup mode. To protect from these voltage spikes, it is recommended to connect a

1N5817 is recommended for through hole and MBRS120T3 is recommended for surface

mount.

Figure 9.

Supply voltage protection

Figure 10.

Crystal accuracy across temperature

Figure 11.

Clock calibration

AI02169

VCC

0.1

µF

DEVICE

VCC

VSS

AI00999

–160

0

10203040506070

Frequency (ppm)

Temperature

°C

80

–10

–20

–30

–40

–100

–120

–140

–40

–60

–80

20

0

–20

ΔF

= -0.038

(T - T

F

ppm

C

2

T

AI00594B

NORMAL

POSITIVE

CALIBRATION

NEGATIVE

CALIBRATION