Datasheet

L6474 Programming manual
Doc ID 022529 Rev 3 41/52
The OSC_SEL and EXT_CLK bits set the system clock source:
The OC_SD bit sets whether or not an overcurrent event causes the bridges to turn off; the
OCD flag in the status register is forced low anyway:
The POW_SR bits set the slew rate value of power bridge output:
Table 23. Oscillator management
EXT_CLK OSC_SEL[2..0] Clock source OSCIN OSCOUT
0 0 0 0
Internal oscillator: 16 MHz Unused Unused
0 0 0 1
0 0 1 0
0 0 1 1
1 0 0 0 Internal oscillator: 16 MHz Unused
Supplies a 2 MHz
clock
1 0 0 1 Internal oscillator: 16 MHz Unused
Supplies a 4 MHz
clock
1 0 1 0 Internal oscillator: 16 MHz Unused
Supplies a 8 MHz
clock
1 0 1 1 Internal oscillator: 16 MHz Unused
Supplies a 16 MHz
clock
0 1 0 0 External crystal or resonator: 8 MHz Crystal/resonator driving
Crystal/resonator
driving
0 1 0 1
External crystal or resonator: 16
MHz
Crystal/resonator driving
Crystal/resonator
driving
0 1 1 0
External crystal or resonator: 24
MHz
Crystal/resonator driving
Crystal/resonator
driving
0 1 1 1
External crystal or resonator: 32
MHz
Crystal/resonator driving
Crystal/resonator
driving
1 1 0 0
Ext. clock source: 8 MHz
(Crystal/resonator driver disabled)
Clock source
Supplies inverted
OSCIN signal
1 1 0 1
Ext. clock source: 16 MHz
(Crystal/resonator driver disabled)
Clock source
Supplies inverted
OSCIN signal
1 1 1 0
Ext. clock source: 24 MHz
(Crystal/resonator driver disabled)
Clock source
Supplies inverted
OSCIN signal
1 1 1 1
Ext. clock source: 32 MHz
(Crystal/resonator driver disabled)
Clock source
Supplies inverted
OSCIN signal
Table 24. Overcurrent event
OC_SD Overcurrent event
1 Bridges shut down
0 Bridges do not shut down