A2557 Allegro MicroSystems, Inc., A2557 Datasheet
A2557
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A2557 Summary of contents
Page 1
... Protected Quad Driver with Fault Detection and Sleep Mode Description The A2557 has been specifically designed to provide cost- effective solutions to relay-driving applications with up to 300 mA drive current per channel. They may also be used for driving incandescent lamps in applications where turn-on time is not a concern ...
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... A2557SLBTR-T Yes A2557EB-T Yes A2557EEB-T Yes A2557EEBTR-T Yes A2557ELB-T Yes A2557ELBTR-T Yes A2557KB – A2557KB-T Yes A2557KEB-T Yes A2557KEBTR-T Yes A2557KLB-T Yes A2557KLBTR – A2557KLBTR-T Yes with Fault Detection and Sleep Mode The packages offer fused leads for enhanced thermal dissipation. ...
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... A2557 Absolute Maximum Ratings Characteristic Logic Supply Voltage Input Voltage Output Voltage Overcurrent Protected Output Voltage Output Current FAULT Output Voltage Package Power Dissipation Operating Ambient Temperature Maximum Junction Temperature Storage Temperature with Fault Detection and Sleep Mode Symbol ...
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... OUT FAULT OUT 8 4 Note that the A2557xB (DIP) and the A2557xLB (SOIC) are electrically identical and share a common terminal number assignment. Copyright © 1998, 2002 Allegro MicroSystems, Inc. Protected Quad Driver GROUND GROUND Dwg ...
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... A2557 ELECTRICAL CHARACTERISTICS over operating temperature range, V Characteristic Symbol Output Leakage Current* Output Sustaining Voltage Output Saturation Voltage Over-Current Limit Input Voltage Input Current Fault Output Leakage Current Fault Output Current Fault Output Saturation Voltage V Clamp Diode Forward Voltage Clamp Diode Leakage Current ...
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... A2557 0 0.2 0 100 200 OUTPUT CURRENT IN MILLIAMPERES 100 200 OUTPUT CURRENT IN MILLIAMPERES with Fault Detection and Sleep Mode TYPICAL OPERATING CHARACTERISTICS 600 500 400 300 400 300 0 Dwg. GP-064 400 300 Dwg ...
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... A2557 CIRCUIT DESCRIPTION AND APPLICATION The A2557 low-current quad power drivers provide protected output driver functions, combined with a fault diagnostic scheme, plus an automatic low-current Sleep-Mode function. These de- vices monitor their outputs for fault (open or shorted) conditions. For each channel the input and output levels are compared. If these are different from the expected levels then a fault condition is fl ...
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... A2557 CIRCUIT DESCRIPTION AND APPLICATION (continued) NORMAL LAMP IN-RUSH CURRENT THERMAL GRADIENT SENSING CURRENT LIMIT I TRIP 0 TIME Inductive load driver Bifi lar (unipolar) stepper motors (and other inductive loads) can be driven directly. The internal diodes prevent damage to the output transistors by suppressing the high-voltage spikes that occur when turning off an inductive load ...
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... A2557 CIRCUIT DESCRIPTION AND APPLICATION (continued) IN FAULT (SHORTED LOAD) FAULT (OPEN LOAD) Under some conditions it is possible to get spurious glitches on the FAULT output at load turn-on and turn-off transitions: • Light load turn-off. Under light loading conditions the turn- off delay (see characteristics above) of the output stage increases and may result in a spurious fault output of a few μ ...
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... A2557 19.05±0. 1.27 MIN +0.25 1.52 –0.38 0.46 ±0.12 with Fault Detection and Sleep Mode B Package, 16-pin DIP with internally fused pins 4, 5, 12, and 13 and external thermal tabs +0.76 +0.38 6.35 10.92 –0.25 –0.25 For Reference Only 5.33 MAX (reference JEDEC MS-001 BB) Dimensions in millimeters +0.51 Dimensions exclusive of mold flash, gate burrs, and dambar protrusions 3.30 – ...
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... A2557 with internally fused pins 5 through 11 and 19 through 25 12.45±0.13 11.51±0.08 0.74 ±0.08 28X 0.10 0.43 ±0.10 A Terminal #1 mark area with Fault Detection and Sleep Mode EB Package, 28-pin PLCC 12.45±0.13 11.51±0. 5.21±0.36 5.21±0.36 For Reference Only (reference JEDEC MS-018 AB) Dimensions in millimeters Dimensions exclusive of mold flash, gate burrs, and dambar protrusions ...
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... A2557 with internally fused pins 4 and 5, and 12 and 13 10.30±0. 16X 0.10 C 1.27 0.41 ±0.10 For Reference Only Pins 4 and 5, and 12 and 13 internally fused Dimensions in millimeters (reference JEDEC MS-013 AA) Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown Copyright © ...