Description VNQ810-E is a quad HSD formed by assembling two VND810-E chips in the same SO28 package. The VNQ810-E is a monolithic device made with STMicroelectronics Vipower M0-3 technology to drive a load child that is grounded on either side. Active VCC pin voltage clamp protects the device from low energy peaks wrapping active current limiting combined with thermal shutdown and automatic restart to prevent device overloading. The device detects load conditions in both open and closed states. A shorted output to VCC is detected in the off state. When the ground pin is disconnected, the unit automatically shuts down.

block diagram

Anti-Battery Ground Protection Network Solution 1: Resistor in Ground Wire (RGND Only) This can be used for any type of load. Here are instructions on how to size the RGND resistors 1) rgnd ≤ 600mv/2 (max(on). 2) RGND±(-VCC)/(-IGND), where -IGND is the DC reverse ground pin current, and can be found in the Absolute Maximum Ratings section of the device data sheet. The power dissipation in RGND (when VCC<0: in reverse battery case) is: PD=(-VCC)2/RGND This resistor can be shared among several different HSDs Please note that this resistor value should be Calculated with Equation (1), where (on)max becomes the sum of the maximum on-state currents of the different devices. Note that if the microprocessor ground is not shared with the device ground, then RGND will shift in the input threshold and the state output value (is(on) max * RGND) In the case of multiple high-side drivers sharing the same rgnd, This shift will vary with multiple devices turned on. ST recommends solution 2 if the calculated power dissipation results in a large resistor or multiple devices must share the same resistor.

Application diagram

Solution 2: Diode in the ground wire (DGND). If the device will be driving an inductive load, a resistor (RGND = 1kΩ) should be inserted in parallel with DGND. This small signal diode can be safely shared among several different high-speed drivers. Also in this case, if the microprocessor ground is not shared with the device ground, the presence of the ground network will create a shift (j600mV) in the input threshold and state output value if multiple HSDs share the same diode/resistor network , then this offset does not change. Series resistors on the input and status lines are also required to prevent currents exceeding the absolute maximum ratings during battery voltage transients. For unused input and status pins, the safest configuration is to leave them unconnected. If the load dump peak voltage exceeds the VCC maximum DC rating, a load dump protection DLD (voltage transient suppressor) is required. The same applies if the device is exposed to transients on the VCC line greater than those shown in the ISO T/R 7637/1 table. µC I/O Protection: If a ground protection network is used and there is a negative transient on the VCC line, then the control pin will be pulled negative. ST recommends inserting a resistor (Rprot) in the line to prevent the μC I/O pins from latching up. The value of these resistors is the leakage current of the μC and the current required by the HSD I/Os (input level compatibility) (latching limit For the compromise between μC I/Os) vccpeak/ilatchup≤rprot≤(vohμc-vih-vgnd)/iihmax calculation example:
For VCCPEAK=-100V and ILATCHUP≥20mA; VOHμC≥4.5V 5KΩ≤RPROT≤65KΩ. The recommended rprot value is 10kΩ. Disconnected load detection In the disconnected state, disconnected load detection requires an external pull-up resistor (RPU) connected between the output pin and the positive supply voltage (VPU), such as the +5V line used to power the microprocessor. The external resistor must be selected according to the following requirements: 1) No false open load indication when connecting the load: In this case, we must avoid VOUT being higher than VOLmin; this will result in the following condition VOUT=(VPU/(RL+RPU))RL 2) No false detection when load is disconnected: In this case, VOUT must be higher than VOLmax; this results in the following situation RPU < (VPU – VOLmax)/IL(off2) because if VOUT is pulled high (up to a few mA), IS (disconnected) can increase significantly, so the pull-up resistor RPU should be connected to the power supply that is disconnected when the module is in standby. The values for VOLmin, VOLmax and IL(off2) are available in the Electrical Characteristics section.