Datasheet

Functional description L9935
14/29 Doc ID 5198 Rev 10
5.2.4 Reversing phase
Suppose the current flowed via M
21
, the load and M
12
before reversing phase. Reversing
phase M
21
and M
12
will be turned off. So now the current will flow through D
22
, the load and
D
11
. This leads to a fast current decay.
5.2.5 Chopper control by oscillator
Both chopping circuits work with offset phase. One chopper will switch on the bridge at the
maximum voltage of the oscillator while the other chopper will switch on the bridge at
minimum voltage of the oscillator.
MS1 and MS2 blank switching spikes that could lead to errors of the current control circuit.
Figure 6. Principal chopper control circuit
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