NJM3777E3# NJR, NJM3777E3# Datasheet
NJM3777E3#
Specifications of NJM3777E3#
NJM#3777E3
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NJM3777E3# Summary of contents
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GENERAL DESCRIPTION The NJM3777 is a switch-mode (chopper), constant-current driver with two channels: one for each winding of a two-phase stepper motor. The NJM3777 is equipped with a Disable input to simplify half-stepping operation. The NJM3777 contains a clock oscillator, ...
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PIN CONFIGURATION Figure 2. Pin configuration PIN DESCRIPTION EMP Symbol Description 1 NC Not connected 2 M Motor output B, channel 1. Motor current flows from Common emitter, channel 1. This pin connects to a sensing ...
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FUNCTIONAL DESCRIPTION Each channel of the NJM3777 consists of the following sections: an output H-bridge with four transistors and four recirculation diodes, capable of driving up to 800 mA continuous current to the motor winding, a logic section that controls ...
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ABSOLUTE MAXIMUM RATINGS Parameter Voltage Logic supply Motor supply Logic inputs Analog inputs Current Motor output current Logic inputs Analog inputs Temperature Operating junction temperature Storage temperature Power Dissipation (Package Data) Power dissipation +25 C GND Power ...
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ELECTRICAL CHARACTERISTICS Electrical characteristics over recommended operating conditions, unless otherwise noted Parameter General Supply current Supply current Total power dissipation Total power dissipation Thermal shutdown junction temperature Turn-off delay Logic Inputs Logic HIGH input voltage Logic LOW ...
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APPLICATIONS INFORMATION Current control The regulated output current level to the motor winding is determined by the voltage at the reference input and the value of the sensing resistor expressed as 0.1• [A] M,peak ...
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Current sense filtering At turn-on a current spike occurs, due to the recovery of the recirculation diodes and the capacitance of the motor winding. To prevent this spike from reseting the flip-flops through the current sensing comparators, the clock oscillator ...
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Dis (Disable) inputs A logic HIGH on the Dis inputs will turn off all four transistors of the output H-bridge, which results in a rapidly decreasing out- put current to zero. V (Reference) inputs R The Vref inputs of the ...
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Full-step mode Both windings are energized at all the time with the same current, I current direction (and the magnetic field direction) in one phase is reversed. The next step is then taken when the other phase current reverses. The ...
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TYPICAL CHARACTERISTICS P (W) D 3.0 2.0 1 0.20 0.40 0.60 0.80 I (A) M Figure 10. Power dissipation vs. motor current ( 1.2 1.0 0.8 0.6 0.4 0 ...