NJM37717 New Japan Radio Co., Ltd., NJM37717 Datasheet
NJM37717
Related parts for NJM37717
NJM37717 Summary of contents
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... GENERAL DESCRIPTION NJM37717 is a stepper motor diver, which consists of a LS-TTL compatible logic input stage, a current sensor, a monostable multivibrator and a high power H-bridge output stage with built-in protection diodes. NJM37717 is a high voltage version and pin compatible with NJM3717. The output current 1200mA. Two NJM37717 and a small number of external components from a complete control and drive unit for stepper moter system ...
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... Reference voltage. Controls the threshold voltage of the comparator and R hence the output current. Input resistance: typically 6.8k M Motor output A, Motor current flows from Common emitter. Connect the sense resistor between this pin and ground. NJM37717 to M when Phase is high resistor and a 820 pF in pins should be wired together on MM ...
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... Figure 3. Definition of terms FUNCTIONAL DESCRIPTION The NJM37717 is intended to drive a bipolar constant current through one motor winding of a 2-phase stepper motor. Current control is achieved through switched-mode regulation, see figure 4 and 5. Three different current levels and zero current can be selected by the input logic. ...
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... For best speed performance of the stepper motor at half-step mode operation, the phase logic level should be changed at the same time the current-inhibiting signal is applied (see figure 6). , which is determined by the timing components R off , it is ignored. off , as an analog voltage. This voltage is fed S NJM37717 , and S and .If a ...
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... Figure 4. Motor current ( Vertical : 200 mA/div, Horizontal: 1 ms/div, expanded part 100 µs/div Figure 6. Principal operating sequence NJM37717 Figure 5. Output stage with current paths for fast and slow current decay ...
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... 10 stg °C) Symbol Min V 4. -1000 NJM37717 Min Max Unit - -1200 +1200 -40 +150 °C -55 +150 °C Typ ...
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... HIGH +25° µs off MM on Symbol Conditions Rthj- DIP package. GND Rth DIP package. Note 2. J-A 2 PCB copper area with free air convection. T NJM37717 = 820 pF Min Typ Max - - 1.4 1 2.8 3.3 =200 - 0.9 1 165 - 2.0 ...
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... CC Before a driver circuit board is removed from its system, all supply voltages must be turned off to avoid destruc- tive transients from being generated by the motor. Figure 8. Typical stepper motor driver application with NJM37717 and ground. MM and circuit GND should be kept as short as possible. This applies also to the C , can be turned on or off in any order ...
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... 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 NJM37717 can be reduced by soldering the ground pins to a suitable copper ground plane on j-a the printed circuit board (see figure 10 applying an external heatsink type V7 or V8, see figure 9. ...
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... Figure 14. Typical upper diode voltage drop vs. recirculating current Figure 12. Typical sink saturation vs. output current Figure 15. Typical power dissipation vs. motor current NJM37717 Figure 13. Typical lower diode voltage drop vs. recirculating current Figure 16. Allowable power dissipation vs. ambient temperature The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions ...