NCV70501 Ver la hoja de datos (PDF) - ON Semiconductor

Número de pieza

componentes Descripción

Fabricante

NCV70501

Micro-Stepping Motor Driver

ON Semiconductor 

NCV70501

TYPICAL APPLICATION SCHEMATIC

The application schematic below shows typical

connections for applications with low axis counts and/or

with software SPI implementation. For applications with

many stepper motor drivers, some “minimal wiring”

examples are shown at the last sections of this datasheet.

VDD

R1

R2

100 nF

C2

VBB

D1

C1

22 uF

VBAT

DIR

NXT

DO

MOTXP

DI

NCV 70501

uC

CLK

MOTXN

CSB

M

MOTYP

RHB

ERRB

MOTYN

GND

Figure 4. Typical Application Schematic NCV70501

Table 9. EXTERNAL COMPONENTS LIST AND DESCRIPTION

Component

Function

Typical Value

Tolerance

Unit

C1

VBB buffer capacitor (Note 15)

22

−20 +80%

mF

C2

VBB decoupling capacitor

100

−20 +80%

nF

R1, R2

Pullup resistor

1...5

$10%

kW

D1

Optional reverse protection diode

E.G. SS16

15. Low ESR < 4 W, mounted as close as possible to the NCV70501. The total decoupling capacitance value has to be chosen properly to reduce

the supply voltage ripple and to avoid EM emission.

FUNCTIONAL DESCRIPTION

H−Bridge Drivers with PWM Control

Two H−bridges are integrated to drive a bipolar stepper

motor. Each H−bridge consists of two low−side N−type

MOSFET switches and two high−side P−type MOSFET

switches. One PWM current control loop with on−chip

current sensing is implemented for each H−bridge.

Depending on the desired current range and the micro−step

position at hand, the RDS(on) of the low−side transistors will

be adapted to maintain current−sense accuracy. A

comparator compares continuously the actual winding

current with the requested current and feeds back the

information to generate a PWM signal, which turns on/off

the H−bridge switches. The switching points of the PWM

duty−cycle are synchronized to the on−chip PWM clock. For

each output bridge the PWM duty cycle is measured and

stored in two appropriate status registers of the motor

controller.

The PWM frequency will not vary with changes in the

supply voltage. Also variations in motor−speed or

load−conditions of the motor have no effect. There are no

external components required to adjust the PWM frequency.

In order to avoid large currents through the H−bridge

switches, it is guaranteed that the top− and bottom−switches

of the same half−bridge are never conductive

simultaneously (interlock delay).

http://onsemi.com

8

Share Link: