The width voltage range of each output current that can drive the dual -stage step motor of up to 750mA is as high as 750mA. Stable motor design power supply voltage internal heat shutdown

Explanation

L6219dsa is a bipolar single -chip integrated circuit control and driving two winding circuit bipolar steps into the motor Or control the two DC motors in two directions. L6219DSA with some external components forms a complete control and driving circuit system controlled by LS TTL or microprocessor control. The power level is a dual -full bridge maintained 46V voltage, including four diode, which is used for current re -cycle. Provide cross -conducting protection to avoid the current direction of cross -conduction while switching. The internal pulse width modulation (PWM) controls the output current to 750mA, and the peak startup current is as high as 1A. From 750mA (each bridge), it allows two logical input and an external voltage benchmark. A phase input each bridge determines the direction of the load current. The disabled output of the thermal protection circuit If the chip temperature exceeds the safety operation limit.

Note: ESD guarantee for ground, VS, VSS, OUT 1A and OUT 2A 8486; 100pf).

Electrical characteristics (TJ -40 to 125 ° C, vs 46V, VSS 4.75V to 5.25V, vREF 5V; uns are unless there are regulations), as shown in Figure 3.

function description

This circuit is used to drive bipolar step motors. The peak current control is adjusted through the switch mode. There are three different current levels to choose two logical input I02-I12 of I01-I11 Winding 2 with two logical inputs of Wind 1 and Wind 1.

The current can also completely turn off the input logic (i0 and i1) to select the current in the motor winding group to have these inputs. (See Figure 2) If any logic input keeps the road, the circuit will treat it with a high level of input.

Phase

This input determines the direction of the current in the winding, depending on the motor connection. The signal is sent to improve the noise resistance through the Schmidt trigger, and is delayed to ensure the output stage during the phase movement. The phase input high level causes the motor current from the exit of the motor to the output B current sensor. This component contains a current influenza resistor (RS), a low -pass filter (RC, CC) and three comparators. There is only one comparison in a state of activity at a time. It is used by the input logic according to current excitement signal iO and i1 select the level. The motor current flows the sensor. When the current increases, the voltage on the RS becomes higher than the reference voltage of another comparator input terminal, and the comparator is higher, which trigger the pulse generator. The maximum peak current IMAX can be defined as:

The pulse generator is the positive edge of the comparator output of a single stable state. During the pulse process, the single -stable output is very high, TOFF, which is determined by time component RT and CT. TOFF 1.1 RTCT single pulse cutting motor winding to reduce the winding current TOFF. If a new trigger signal appears during the TOFF period, it is ignored.

Output level

The output level contains four Darlingon transistors (source drives) and four saturated transistors (receiver drives) and eight diode, two connected H bridges. The source transistor is used to switch the power supply to the motor, thereby driving the constant current through the winding. But it should be noted that this is not allowed to make the output short circuit. In order to increase the current level of the motor current.

VS, VSS, VREF

The circuit will withstand any connection or disconnection order of the power supply voltage VS and VSS. Normal DV/DT then assume a value. VREF is best to establish and power off if VS is established. Application information (Note 1) Some step motors are not designed to run continuously at the maximum current. As a circuit, the constant current temperature is driven by the motor at the temperature at both temperatures. Moreover, some step motors have such high cores that are not suitable for the loss of the current regulations for switching modes. Unused inputs should be connected to the appropriate voltage level to obtain the highest noise interference. When the circuit is adjusted during the operation of the switch mode, the problem of interference may occur in some applications. A good scale and then use 100NF to decompose the capacitor with a power cord and ground near the component. The ground wire between RS and circuit GND should be as short as possible. The typical application circuit is shown in Figure 3. Note that CT must be NPO or similar types. Sensing winding current, parallel metal is recommended to use a film resistor (RS) Note 1-Other information provides power development systems in the form of Smart :

Test board HWL6219DSA (step drive)

Software SWL6219DSA (Soft Disk)

Figure 3: Typical application circuit. (Reference of pin output

DIP24 package)