L9947 datasheet(7/13 Pages) STMICROELECTRONICS

Part #	L9947

Description	QUAD HALF-BRIDGE AND SINGLE HIGH-SIDE DRIVER

PDF	13 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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7 / 13 page

SYSTEM STARTUP (figure 2)

It is not mandatory that VS is present before VCC.

With the presence of the VCC the internal logic

would be reseted and the system restarts under

control of the inputs. If CSN = 0 for more than

100

µs after the presence of VCC the standby

mode is activated. Standby is also activated when

the CSN and VCC would be high at the same

time. When CSN = 0 and VCC goes up, the device

is not controlled by the bus. The outputs remain in

tristate but the current consumption is larger than

100

µA. A high - low - signal at the CSN - wire is

mandatory to control the outputs. There is no un-

dervoltage detection level for the supply voltage

VS implemented. The VCC should be supplied

from the same voltage supply as the driver of the

D0 -D3 pins (eg.

µC).

Figure 2: System Startup Sequence

L9947

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L9947 Datasheet(PDF) 7 Page - STMicroelectronics