DS10473 Rev 2

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STPA003

General information

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5.2

Battery variations

5.2.1

Low voltage operation

Most recent OEM specifications require automatic stop for car engine at traffic lights, in

order to reduce emissions of polluting substances. The STPA003, thanks to its innovating

design, allows a continuous operation when battery falls down. At 6 V it is still fully

operational, only the maximum output power is reduced according to the available voltage

supply.

If the battery voltage drops below the minimum operating voltage of 6 V the amplifier is fast

muted, the capacitor on SVR is discharged and the amplifier restarts when the battery

voltage returns to the correct voltage.

5.2.2

Cranks

STPA003 can sustain worst case cranks from 16 V to 6 V, continuing to play and without

producing any pop noise.

Examples of battery cranking curves are shown below, indicating the shape and duration of

allowed battery transitions.

Figure 22. Battery cranking curve example 1

V1 = 16 V; V2 = 6 V; V3 = 7 V; V4 = 8 V

t1 = 2 ms; t2 = 50 ms; t3 = 5 ms; t4 = 300 ms; t5 =10 ms; t6 = 1 s; t7 = 2 ms

GAPGPS00674

V

5

(V)

batt

t (s)