UDN2916A datasheet(6/8 Pages) STMICROELECTRONICS

6 / 8 page

The circuit will stand any order of turn-on or turn-

off the supply voltages VS and VSS. Normal dV/dt

values are then assumed.

Preferably, VRef should be tracking VSS during

power-on and power-off if VS is established.

APPLICATION INFORMATIONS (Note 1)

Some stepper motors are not designed for contin-

uous operation at maximum current. As the circuit

drives a constant current through the motor, its

temperature might increase exceedingly both at

low and high speed operation.

Also, some stepper motors have such high core

losses that they are not suited for switch mode

current regulation.

Unused inputs should be connected to proper

voltage levels in order to get the highest noise im-

munity.

As the circuit operates with switch mode current

regulation,

interference

generation

problems

might arise in some applications. A good measure

might then be to decouple the circuit with a 100nF

capacitor, located near the package between

power line and ground.

The ground lead between Rs, and circuit GND

should be kept as short as possible.

A typical Application Circuit is shown in Fig. 3.

Note that Ct must be NPO type or similar else.

To sense the winding current, paralleled metal

film resistors are recommended (Rs)

Note 1 - Other information is available as ”Smart

Power Development System”: HWPC2916A.

Figure 3: Typical Application Circuit.

UDN2916A

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UDN2916A Datasheet(PDF) 6 Page - STMicroelectronics