NJM3770AD3 NJR, NJM3770AD3 Datasheet
NJM3770AD3
Specifications of NJM3770AD3
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NJM3770AD3 Summary of contents
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... Packages DIP16 (Batwing) / PLCC28 / EMP20 BLOCK DIAGRAM Phase GND Figure 1. Block diagram STEPPER MOTOR DRIVER V CC Schmitt Time Trigger Delay & & & & + – + – Monostable + t = 0.69 • R • C off T – Current Sensor T C NJM3770A PACKAGE OUTLINE NJM3770AD3 NJM3770AE2 NJM3770AFM2 Output Stage T NJM3770A E ...
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PIN CONFIGURATIONS GND 4 NJM GND GND 5 16 3770AE2 15 6 GND GND GND 7 GND ...
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FUNCTIONAL DESCRIPTION The NJM3770A is intended to drive a bipolar constant current through one winding of a 2-phase stepper motor. Current control is achieved through switched-mode regulation, see figure 3 and 4. Three different current levels and zero current can ...
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Current level selection. The status of I and I inputs determines the current level in the motor winding. Three fixed current levels can selected according to the table below. Motor current High level ...
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ABSOLUTE MAXIMUM RATINGS Parameter Voltage Logic supply Motor supply Logic inputs Comparator input Reference input Current Motor output current Logic inputs Analog inputs Temperature Operating junction temperature Storage temperature RECOMMENDED OPERATING CONDITIONS Parameter Logic supply voltage Motor supply voltage Motor ...
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ELECTRICAL CHARACTERISTICS Electrical characteristics over recommended operating conditions. C Parameter General Supply current Total power dissipation Turn-off delay Thermal shutdown junction temperature Logic Inputs Logic HIGH input voltage Logic LOW input voltage Logic HIGH input current Logic LOW input current ...
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APPLICATIONS INFORMATION Motor selection Some stepper motors are not designed for continuous operation at maximum current. As the circuit drives a constant current through the motor, its temperature can increase, both at low- and high-speed operation. Some stepper motors have ...
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Analog control As the current levels can be continuously controlled by modulating the V achieved. Sensor resistor The R resistor should noninductive type power resistor. A 0.5 ohm resistor, tolerance S choice for 800 mA max motor ...
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Heatsinking The junction temperature of the chip highly effects the lifetime of the circuit. In high-current applications, the heatsinking must be carefully considered. The Rth of the NJM3770A can be reduced by soldering the ground pins to a suitable copper ...
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TYPICAL CHARACTERISTICS V (V) Sat 1.8 1.6 1 125 .40 .80 1.2 I (A) M Figure 11. Typical source saturation vs. output current ...