L9969X datasheet(31/70 Pages) STMICROELECTRONICS

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Symbol

Parameter

Condition

Min

Typ

Max

Unit

CF maximum output voltage

-100 mV

VDD + 200

This current feedback signal could be used for certain applications. To get the direction of the current, the signal

DIR (HBR control by parallel inputs) or alternatively the information from CONFIG_REG.DIR is used (HBR control

by SPI).

Only positive current (from Outx to GND) at the low side power stage is indicated at the CF output. Negative

current and current over the bulk diode are not visible.

3.2.6.2

Current limitation

The output stage current limitation levels are adjustable in 3 different ranges, as described in Table 18. The limits

are guaranteed over the complete temperature range.

Figure 18. Parameters during current limitation

IOUT

Current Limit

Hysteresis IHYS

ICL

Blanking

Time tb

Time between two

transients (load

dependent )

Table 18. Current limitation ranges

Symbol

Parameter

Condition

Min

Typ

Max

Unit

ICL2

Current limit, selection 2

4.25

5.0

5.75

ICL3

Current limit, selection 3 (default)

5.6

6.5

7.6

ICL4

Current limit, selection 4

7.3

8.5

9.9

ICL_HYST

Current limit, hysteresis

-10

-5

Current limit, blanking time

µs

Note:

in case of load dump with current limitations, SR=00 setting should be avoided, especially in conjunction with

CL3/CL4 settings.

Because the current levels are programmed by SPI, the default value is always ‘switch off current level’ = 3.

A change in one or both input pins terminates the current limitation and the outputs follow the inputs respectively.

If the current limitation is running and a load with a high inductive component is connected, the free wheeling may

take much time. If the signal on the inputs stays unchanged, the free wheeling will last as long as the lower limit

(IL - Ihys) is reached. After that, the path gets active again, the current rises until IL is reached, then an additional

increase follows for tb and then free wheeling is restarted again, in case PWM is still active.

The time between two transients is mainly related to the time constant of the load, and hence not specified. This

time however, cannot drop below the limit ttrans_lim defined in Table 19.

The information that the function “Current limitation” is active is stored in the DIA_REG2.

L9969x

Functional description

DS14029 - Rev 6

page 31/70

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