參數(shù)資料
型號: LMD18245
廠商: National Semiconductor Corporation
英文描述: 3A, 55V DMOS Full-Bridge Motor Driver
中文描述: 第3A,55V的DMOS全橋式電動機驅(qū)動器
文件頁數(shù): 13/18頁
文件大小: 647K
代理商: LMD18245
The Typical Application
(Continued)
HALF STEP DRIVE WITH TORQUE COMPENSATION
To make the motor take half steps, the windings can also be
energized with sinusoidal currents (Figure 11). Controlling
the winding currents in the fashion shown doubles the step
resolution without the significant torque ripple of the prior
drive technique. The motor takes one half step each time the
level of either winding current changes. Half step drive with
torque compensation is microstepping drive. Along with the
obvious advantage of increased step resolution, microstep-
ping reduces both full step oscillations and resonances that
occur as the motor and load combination is driven at its natu-
ral resonant frequency or subharmonics thereof. Both of
these advantages are obtained by replacing full steps with
bursts of microsteps. When compared to full step drive, the
motor runs smoother and quieter.
Figure 12 shows the lookup table for this application of the
typical application circuit. Dividing 90electrical per full step
by two microsteps per full step yields 45 electrical per mi-
crostep.
α
, therefore, increases from 0 to 315 in increments
of 45. Each full 360 cycle comprises eight half steps.
Rounding |cos
α
| to four bits gives D A, the decimal equiva-
lent of the binary number applied at M4 A through M1 A. DI-
RECTION A controls the polarity of the current in winding A.
Figure 11 shows the sinusoidal winding currents.
DS011878-22
Top Trace: Phase A Winding Current at 1A/div
Bottom Trace: Phase B Winding Current at 1A/div
Horizontal: 1 ms/div
*500 steps/second
DS011878-23
BRAKE A = BRAKE B = 0
FIGURE 10. Winding Currents and Digital Control Signals for Half Step Drive without Torque Compensation
13
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相關代理商/技術參數(shù)
參數(shù)描述
LMD18245_06 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3A, 55V DMOS Full-Bridge Motor Driver
LMD18245T 功能描述:馬達/運動/點火控制器和驅(qū)動器 RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube
LMD18245T 制造商:Texas Instruments 功能描述:HALF BRIDGE 3A 55V 18245 TO22015
LMD18245T/HALF 制造商:Texas Instruments 功能描述:HALF BRIDGE 3A 55V 18245 TO22015
LMD18245T/LF15 功能描述:馬達/運動/點火控制器和驅(qū)動器 RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube