Datasheet LT1190 (Analog Devices) - 10

LT1190
U U W U APPLICATIO S I FOR ATIO
The ability to maintain shutoff is shown on the curve Other precautions include: Shutdown Supply Current vs Temperature in the Typical 1. Use a ground plane (see Design Note 50, High Fre- Performance Characteristics section. At very high quency Amplifier Evaluation Board). elevated temperatures it is important to hold the shut- down pin close to the negative supply to keep the supply 2. Do not use high source impedances. The input current from increasing. capacitance of 2pF and RS = 10k for instance, will give an 8MHz – 3dB bandwidth.
Murphy Circuits
3. PC board socket may reduce stability. There are several precautions the user should take when 4. A feedback resistor of 1k or lower reduces the effects of using the LT1190 in order to realize its full capability. stray capacitance at the inverting input. (For instance, Although the LT1190 can drive a 50pF load, isolating the closed-loop gain of 2 can use R capacitance with 10Ω can be helpful. Precautions prima- FB = 300Ω and RG = 300Ω.) rily have to do with driving large capacitive loads.
Driving Capacitive Load Driving Capacitive Load
LT1190 • TA11 LT1190 • TA12 AV = –1, IN DEMO BOARD, CL = 50pF AV = –1, IN DEMO BOARD, CL = 50pF WITH 10Ω ISOLATING RESISTOR
Murphy Circuits
5V 5V 5V 3 7 3 3 7 7 + + + COAX 6 6 6 LT1190 LT1190 LT1190 2 2 2 – 4 – 4 – 4 1X SCOPE –5V –5V –5V PROBE SCOPE PROBE LT1190 • TA13
An Unterminated Cable Is A 1X Scope Probe Is a A Scope Probe on the Inverting a Large Capacitive Load Large Capacitive Load Input Reduces Phase Margin
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