MB3878
■BLOCK DIAGRAM
−INE1 8 |
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OUTC1 10 | <Current Amp.1> | <Error | VREF |
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+INC1 13 | + | Amp.1> |
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| ⋅ 25 | − |
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−INC1 12 | − | + |
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| 21 VCC (O) |
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+INE1 9 |
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| <PWM Comp.> |
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FB1 7 |
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| + | <OUT> |
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| + |
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| + |
| Drive | 20 OUT |
−INE2 4 |
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| − |
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OUTC2 2 | <Current Amp.2> | <Error |
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| VCC |
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| VREF |
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+INC2 24 | + | Amp.2> |
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− |
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| ⋅ 25 |
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| 19 VH | |
−INC2 1 | − | + |
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| Bias |
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| Voltage | (VCC − 5 V) | ||
+INE2 3 |
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| <VH> |
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FB2 5 |
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| 2.5 V |
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| 1.5 V |
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| <UVLO> |
| VCC |
| <Error |
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| VREF |
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| Amp.3> |
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−INE3 16 | − | (VCC UVLO)215 kΩ | ||
+ |
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| + |
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OUTD 11 | + | − | 35 kΩ | |
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4.2 V |
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| 0.91 V |
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| (0.77 V) |
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FB3 15 |
| VREF |
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<SOFT> | UVLO |
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VREF |
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∝A |
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1 |
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| VCC |
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CS 22 | bias |
| 18 | VCC |
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<OSC> | <REF> | <CTL> | 14 | CTL |
(45 pF) | VREF |
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17 | 6 5.0 V | 23 |
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RT | VREF | GND |
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4
