SLA7026M Allegro Microsystems Inc, SLA7026M Datasheet - Page 9

• Manufacturer Part Number: SLA7026M
• Description: IC, MOTOR CTRL/DRVR, STEPPER, 3A, SIP-18
• Manufacturer: Allegro Microsystems Inc

Specifications of SLA7026M

• Motor Type: Stepper
• No. Of Outputs: 4
• Output Current: 3A
• Output Voltage: 100V
• Supply Voltage Range: 10V To 44V
• Driver Case Style: SIP
• No. Of Pins: 18
• Operating Current: 15mA
• Operating Temperature Classification: Commercial
• Package Type: Power-Tab SIP
• Operating Supply Voltage (min): 10V
• Operating Supply Voltage (typ): 24V
• Operating Supply Voltage (max): 44V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

SLA7024M, SLA7026M,
HIGH-CURRENT PWM,
UNIPOLAR STEPPER MOTOR
CONTROLLER/DRIVERS
AND
DETERMINING THE MOTOR PWM FREQUENCY
and C
Recommended circuit constants and t
POWER DISSIPATION CALCULATIONS
approximately 2.0 A at +65 C (with 2-phase operation), the need for heat
sinks is rare. The basic constituents of conduction losses (internal power
dissipation) include:
(a) FET output power dissipation (I
(b) FET body diode power dissipation (V
(c) control circuit power dissipation (V
(wave drive, half-step, or 2-phase). Assuming a 50% output duty cycle:
Wave Drive = 0.5 (I
Half-Step = 0.75 (I
2-Phase = (I
SMA7029M
The modules function asynchronously, with PWM OFF time fixed by R
Excepting high-current applications utilizing the SLA7026M above
Device conduction losses are calculated based on the operating mode
1
at input t
t
OFF
t
V
R
C
OFF
50
40
30
20
10
b
3
1
0
= 5 V
= 47 k
= 470 pF
0
= 12 s
OUT
PWM FREQUENCY vs MOTOR RESISTANCE
-R
2
d
• r
. The OFF time can be calculated as:
3
OUT
• C
DS(on)
2
OUT
2
1
R
L/R = 1 to 3 ms
2
• r
• log
S
) + (V
• r
MOTOR RESISTANCE in OHMS
= 1
DS(on)
DS(on)
4
n
(1 -
SD
) + 0.75 (V
) + 0.5 (V
FIGURE 7.
• I
6
V
2
OUT
OUT
b
)
) + (V
CC
OFF
2
• r
V
SD
SD
• I
SD
CC
8
are:
DS(on)
CC
= 36 V
• I
CC
• I
• I
V
CC
).
OUT
OUT
OUT
• 15 mA)
or I
= 24 V
10
) + (V
), and
) + (V
OUT
CC
• V
CC
12
• 15 mA)
• 15 mA)
DS(ON)
Dwg. GK-016
14
),
20
25
30
35
40
(5)
3