L9958SB STMicroelectronics, L9958SB Datasheet - Page 20

• Manufacturer Part Number: L9958SB
• Description: IC H-BRIDGE SPI POWERSO16
• Manufacturer: STMicroelectronics

Specifications of L9958SB

• Applications: DC Motor Driver, Brushless (BLDC)
• Number Of Outputs: 2
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: PowerSO-16 Exposed Bottom Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Diagnostics and protections
5.2
5.2.1
5.2.2
5.2.3
5.2.4
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Protection and on state diagnostics
L9958 is protected against short circuits, overload and invalid supply voltage by the following
measures.
Over-current on high-side - short to ground
The high-side switches are protected against a short of the output to ground by an over-
current shutdown. If a high-side switch is turned on and the current rises above the short
circuit detection current Ioc all output transistors are turned off after a filter time Toc_ls and
the error bits "overcurrent on high side 1 (2)", OC_HS1 (OC_HS2) are stored in the internal
status register.
Over-current on low-side - short to Vs
Due to the chopper current regulation, the low-side switches are already protected against a
short to the supply voltage. To be able to distinguish a short circuit from normal current limit
operation, the current limitation is deactivated for the blanking time t
exceeded the current limit threshold IH. If the short circuit detection current I
within this blanking time, a short circuit is detected. All output transistors are turned OFF
and the according error bit “Over-Current on Low Side 1 (2)”, OC_LS1 (OC_LS2) is set.
Short circuit over-load
If, during the Blanking time (t
threshold; after a filtering time, the output MOS are switched OFF and the “Short circuit over
load” can be checked by the reading of the overcurrent bits of the DIA_REG (please refer to
Table 8
Figure 15. Diagnostics for SCB / SCOL
Open load in on state
To perform the Open Load diagnosis in ON state, the flag OL_ON has to be set high through
SPI. After every open load diagnosis in ON state, the OL_ON flag is resetted, to perform a
new open load diagnosis in ON state the OL_ON flag has to be set again.
bit 8, 9,10 and 11).
b
) of the current regulation mode, the current reaches the I
Doc ID 17269 Rev 2
b
after the current has
oc
is reached
L9958
oc