65V, 7.6A High Current Single H-Bridge with Integrated Current Sense

The MAX22205 integrates a high current 65V, 7.6AMAX H-Bridge to drive one Brushed DC motor or one half Stepper motor. The H-Bridge FETs feature very low impedance, resulting in high driving efficiency and low heat. The typical total RON (high-side + low-side) is 0.15Ω. The H-Bridge can be PWM controlled by two logic inputs (DINA, DINB). A third Enable (EN) logic input can be used to configure the outputs to high impedance for coasting the motor.

The MAX22205 features an accurate optional Current Drive Regulation (CDR), which can be used to limit the start up current of a Brushed DC motor or control the phase current for stepper operation. The bridge output current is sensed by a non-dissipative Integrated Current Sensing (ICS) and it is then compared with the desired threshold current. As soon as the bridge current exceeds the threshold (ITRIP), the device enforces the decay for a fixed OFF-time (tOFF). The non-dissipative ICS eliminates the bulky external power resistors normally required for this function, resulting in a dramatic space and power saving compared with mainstream applications based on the external sense resistor. A current proportional to the internally-sensed motor current is output to the analog pins (ISENA, ISENB) to monitor current. Also, one open-drain output (CDR pin) is asserted every time the internal current regulation is taking control of the driver so that the activity of the internal current loop can be monitored.

The maximum output current per H-Bridge is IMAX = 7.6AMAX limited by the Overcurrent Protection (OCP). The device delivers up to 4ARMS at VM = +24V and TA = 25°C with proper PCB ground plane for thermal dissipation. The current capability depends on the PCB thermal characteristic (PCB ground planes, heatsinks, ventilation, etc.).

The MAX22205 features Overcurrent Protection (OCP), Thermal Shutdown (TSD), and Undervoltage Lockout (UVLO). An open-drain active low FAULT pin is activated every time a fault condition is detected. During Thermal Shutdown and Undervoltage Lockout, all the channels are disabled until normal operating conditions are restored.

The MAX22205 is packaged into a small TQFN38 5mm x 7mm and TSSOP38 9.7mm x 4.4mm packages.

Applications

* Brushed DC Motor Driver

* Latched Valves

* Solenoid Driver

* Stepper Motor Driver

* One H-Bridge with +65V Voltage Rating

* Total RDS(ON) (High-Side + Low-Side): 150mΩ Typical (TA = 25°C)

* Current Ratings per H-Bridge (Typical at 25°C):

* IMAX = 7.6AMAX (Impulsive Current for Driving Capacitive Loads)

* IFS = 6A (Max Full Scale Current Setting for Internal Current Drive Regulation)

* IRMS = 4ARMS (TA = 25°C, VM = +24V)

* Integrated Current Control

* Full-Scale DAC Current Configurable with External Resistance

* Internal Current Sensing (ICS) Eliminates External Bulky Resistors and Improves Efficiency

* Current Drive Regulation Monitor Output Pin (CDR Pin)

* Integrated DAC Sets the Output Current Level among 16 Values

* Multiple Decay Modes (Slow, Mixed, Fast)

* Fixed OFF Time Configurable with External Resistance