TMC6300-LA-T

POWER DRIVER FOR BLDC/PMSM MOTORS INTEGRATED CIRCUITS TMC6300 Datasheet Highly Efficient Low Voltage, Zero Standby Current Driver for 3-Phase BLDC/PMSM Motors up to 2A peak, Triple Half-Bridge with separate HS and LS control signals. APPLICATIONS IOT & Handheld devices Battery operated motors Printers, POS Toys Office and home automation CCTV, Security HVAC Mobile medical devices FEATURES AND BENEFITS Voltage Range 2V (1.8V) … 11V DC: Battery Operation min. 2 AA / NiMh cells, or 1-2 Li-Ion cells 3-Phase motors up to 2A (peak) Direct Bridge control for BLDC or PMSM sine-commutation Standby 10µF near pin with shortest possible loop to GND pad. Leave this pin open Foot point of bridge W. Connect to GND directly, or via a sense resistor. Connect the exposed die pad to a GND plane. Provide as many as possible vias for heat transfer to GND plane. 5 TMC6300 DATASHEET (Rev. 1.04 / 2020-JUN-02) 3 6 Sample Circuits The sample circuits show the connection of external components in different operation and supply modes. The connection of the microcontroller is left out for clarity. 3.1 Standard Application Circuit The 3-phase driver offers three half-bridges with individual enable signals for low-side and high-side. It allows driving a PMSM- or a BLDC-motors. In case a current measurement is desired, a common foot point shunt resistor can be added. Keep voltage drop in this resistor to maximum 400mV for normal operation. Take care to keep power supply ripple due to chopper operation at a few 100mV, max., especially when low voltage operation is desired. Use a ceramic, or low ESR capacitors for filtering the power supply. The capacitors need to cope with the current ripple caused by chopper operation. A minimum capacity of 100µF electrolytic, or 10µF ceramic capacitor near the driver is recommended to keep ripple low. Actual demand will depend on the internal power supply resistance and the desired motor current. VCC_IO can be supplied from a separate supply, e.g. a 3.3V regulator, or be driven by a microcontroller port pin. If more than two bridges are switched on at the same time (within 1µs), a capacitor on pin VCP is recommended. The diagnostic output signals any overcurrent or overtemperature condition. The motor driver automatically restarts after power-up, or after cycling VIO_NSTDBY pin. VCP 100n Optional external capacitor 1.8VOUT Place near IC with short path to die pad 1n-100n 10V +VM VS TMC6300 1.8V Voltage regulator STANDBY 100n Internal charge pump 10µ Or low ESR 100µF electrolytic / depending on supply resistance and motor current W Bridge W UL UH BRW VL Individual output control for low-side and high-side driver BBM logic VH 1.8V to 5V I/O voltage / standby Bridge V WL WH Driver error S V DIAG Diagnostic Output VIO/ NSTDBY 100n BRUV B. Dwersteg, © TRINAMIC 2016 Standby detector U Bridge U STANDBY BRUV RS 500k Figure 3.1 3-Phase Motor Driver www.trinamic.com GND DIE PAD GND GND Connect directly to GND plane N TMC6300 DATASHEET (Rev. 1.04 / 2020-JUN-02) 7 3.2 Highly Efficient Driver The TMC6300 integrates a highly efficient power stage, offering low RDSon even at low supply voltages, due to its internal charge pump. This enables high motor current drive capability and low power dissipation for battery powered applications. RDSon vs. VS 400,00 350,00 300,00 250,00 200,00 150,00 100,00 50,00 0,00 1,5 2,0 2,5 RDSon (LS) [mOhm] 3,0 3,5 4,0 RDSon(HS) [mOhm] Figure 3.2 RDSon Variation over Supply Voltage When operating at a high motor current, the driver power dissipation due to MOSFET switch onresistance significantly heats up the driver. This power dissipation will significantly heat up the PCB cooling infrastructure, if operated at an increased duty cycle. This in turn leads to a further increase of driver temperature. An increase of temperature by about 100°C increases MOSFET resistance by roughly 50%. This is a typical behavior of MOSFET switches. Therefore, under high duty cycle, high load conditions, thermal characteristics have to be carefully taken into account, especially when increased environment temperatures are to be supported. Refer the thermal characteristics and the layout hints for more information. As a thumb rule, thermal properties of the PCB design become critical for the tiny QFN 3mm x 3mm package at or above 1.4A motor current for increased periods of time. For currents above 1.4A, a 4-layer PCB layout with 5 via contact of the die attach pad to the GND plane is required. Keep in mind that resistive power dissipation raises with the square of the motor current. On the other hand, this means that a small reduction of motor current significantly saves heat dissipation and energy. Pay special attention to good thermal properties of your PCB layout, when going for 1.4A current or more. www.trinamic.com TMC6300 DATASHEET (Rev. 1.04 / 2020-JUN-02) 8 3.3 Low Power Standby Battery powered applications, and mains powered applications conforming to energy saving rules, often require a standby operation, where the power-supply remains on, but current draw goes down to a low value. Control TMC6300 standby operation by the VIO_NSTDBY pin: Switch off the I/O voltage by pulling this pin to GND. At the same time make sure, that no digital input pin is at a high level. An input level above VIO_NSTDBY would hinder pulling down VIO_NSTDBY, due to the ESD protection diodes in each digital I/O pin. These diodes clamp each input to a level between GND and the IO supply voltage VIO_NSTDBY. Prior to going to standby, stop the motor and go to a low coil current condition, or switch off the motor driver completely. 3.4 Very Low I/O Voltage Operation µC powered with 1.8V +-10% I/O voltage 100n 1.8V Voltage regulator Control Signals Standby 1K Powerup 1.8VOUT In cases, where an I/O voltage of 1.8V (or even lower, due to tolerance) is to be used, the VIO undervoltage threshold level might be too high, to safely release the TMC6300 from reset state. A simple way to avoid the need for an additional I/O voltage regulator (e.g. 2V type), is to use the internal 1.8V regulator to self-supply the TMC6300 VIO pin. In order to allow power-up, the voltage on pin at VIO/NSTDBY has to be forced to min. 1.4V. In order to go back to low power standby, pull it down to less than 0.6V. A PNP transistor gives a low resistive switch to supply VIO. STANDBY Digital I/O BC858B VIO/ NSTDBY Standby detector 470R 100n STANDBY 500k Figure 3.3 Additional Circuit for I/O voltage