SNVSBJ0B December 2019 – August 2021 LM5170
PRODUCTION DATA
Figure 8-2 shows the external and internal configuration for the VIN and VINX pins. Both are rated at 100 Vdc. The VIN pin must be directly connected either to the voltage rail of the HV-Port, or through a small RC filter consisting of 10- to 20-Ω resistor and 0.1-µF to 1-µF bypass capacitor. The VIN pin supplies the internal 330-µA current source supplying the BRKG pin.
A cutoff switch connects and disconnects the VIN and VINX pins. When the UVLO pin voltage is greater than 2.5 V, and when the VCC voltage is greater than 8.5 V, the switch is closed and the VINX and VIN pins are connected.
The VINX pin serves as the supply pin for the RAMP generators (see Figure 8-2 and Section 8.3.9 for details). It is also the high-side terminal of the internal 3-MegΩ pullup resistor for the OVPA pin (see Section 8.3.17 for details). Moreover, it serves as the HV-Port voltage sense for internal circuit use during operation.