BTN8960 /62 /80 /82 High Current PN Half Bridge About this document Scope and purpose This Application Note is intended to provide information and hints for a high current design, using PWM control with the NovalithIC half-bridge family BTN89xy for the automotive environment. Note: The following information is only given to help with the implementation of the device and shall not be regarded as a description or warranty of a certain functionality, condition or quality of the device. Abstract This family contains one P-channel high-side MOSFET and one N-channel low-side MOSFET with an integrated driver IC in one package. The NovalithIC BTN89xy is the interface between the microcontroller and the motor, equipped with diagnostic and protection functions. VS Undervolt. Current detection Sense Overcurr. Detection HS Overtemp. Gate Driver detection HS I S OUT Digital Logic LS off HS off I N Gate Driver LS I NH Overcurr. Detection Slewrate SR Adjustment LS GND Figure 1 Block Diagram BTN89xy As both the high-side and low side switch are placed on one single leadframe this results in many system benefits: Resulting from the low distance between the high-side MOSFET and the low-side MOSFETthe stray inductance between them is minimal thus minimizing negative voltage spikes at OUT during switching and improving EMC. As the voltage level of the leadframe is on the output of the half-bridge, only one single cooling area is required (on OUT potential) for the device, thus being used for both a high-side or low-side current switching. For a state of the art N-channel solution, usually two cooling areas are required, each for the high- side and low-side MOSFET. Application Note Please read the Important Notice and Warnings at the end of this document Rev. 0.6 www.infineon.com 2017-02-21BTN8960 /62 /80 /82 High Current PN Half Bridge Table of contents Due to the p-channel highside switch the need for a charge pump is eliminated thus minimizing EMI. Interfacing to a microcontroller is made easily by the integrated driver IC which features logic level inputs, diagnosis with current sense, slew rate adjustment, dead time generation and protection against overtemperature, undervoltage, overcurrent and short circuit. Table of contents About this document . 1 Table of contents . 2 1 Motor Configurations . 5 1.1 Half-bridge configuration for mono-directional motor control 5 1.2 H-Bridge configuration for bidirectional motor control 6 2 Parasitic Inductance 7 TM 2.1 Measuring signals at NovalithIC . 7 3 Design Guideline . 9 3.1 Schematic and layout design rules 9 3.2 DC-link capacitor . 11 3.2.1 Calculation of the DC-link capacitor and Pi-filter . 11 3.2.2 Undervoltage toggling 13 3.3 Ground references 15 3.4 Driving inductive loads over long wires . 16 3.4.1 PWM operation . 16 3.4.2 Current sense 17 3.5 Reverse polarity protection 17 3.6 Cooling 17 4 Current Sense Improvement . 19 4.1 Characteristic of the dk . 19 ILIS 4.1.1 Supply voltage dependency of dk 19 ILIS 4.1.2 Life time drift .20 4.1.3 Temperature drift of the dk 20 ILIS 4.1.4 Temperature drift of the dk including aging . 27 ILIS 4.2 Offset compensation . 28 4.3 Device specific dk 29 ILIS 4.4 Device fine dk and temperature compensation . 30 ILIS 4.4.1 An example of the I failure with a rough temperature estimation . 31 IS 4.5 IS-pin current sensing and fault detection 31 4.5.1 Current sensing concepts in applications 31 4.5.1.1 BTN89xy - advanced current sense and fault diagnosis . 32 4.5.1.2 BTN79xy current sense limitations . 33 4.5.2 Fault detection . 34 4.5.2.1 Temperature drift of the IS-pins current in fault condition I 40 IS(lim) Application Note 2 Rev. 0.6 2017-02-21