小型放大器高速地驱动重容性负载

寄生电容潜藏在电路的每个角落，当调整电路中容性负载过重时，仔细选择运算放大器成为关键，以实现电压转换率、电流输出能力、功耗、反馈环路稳定性的最优化。可考虑用现有的小封装功率增强型放大器驱动重容性负载，也可采用电流反馈放大器如LT1397实现超宽带电路。
Tiny Ampliers Drive Heavy Capacitive Loads at Speed
Design Note 429
Keegan Leary and Brian Hamilton

Introduction With a package that has a thermal resistance of 135°C/W,
Parasitic capacitance lurks behind every corner of an this much continuous power would result in a 148°C rise
electronic circuit. FET gates, cabling, ground and power in die temperature. If the ambient temperature is 85°C,
planes all add to the Farad bottom line. When the capaci- this brings the die to a package-melting 233°C!
tive load gets heavy in high speed circuits, careful op amp To isolate CLOAD from the amplier, a design could use
selection is paramount for optimizing slew rate, current a series resistor, RS. This technique ultimately limits