Datasheet LT1363 (Analog Devices) - 9

LT1363
W U TYPICAL PERFORMANCE CHARACTERISTICS Large-Signal Transient Large-Signal Transient Large-Signal Transient (AV = 1) (A (A V = –1) V = 1, CL = 10,000pF)
1363 TA34 1363 TA35 1363 TA36
U U W U APPLICATIONS INFORMATION
The LT1363 may be inserted directly into AD817, AD847, The parallel combination of the feedback resistor and gain EL2020, EL2044, and LM6361 applications improving setting resistor on the inverting input can combine with both DC and AC performance, provided that the nulling the input capacitance to form a pole which can cause circuitry is removed. The suggested nulling circuit for the peaking or oscillations. For feedback resistors greater LT1363 is shown below. than 5kΩ, a parallel capacitor of value
Offset Nulling
CF > RG x CIN/RF V+ should be used to cancel the input pole and optimize 3 7 + dynamic performance. For unity-gain applications where 6 LT1363 a large feedback resistor is used, CF should be greater 4 2 – than or equal to C 8 IN. 1 10k
Capacitive Loading
V– The LT1363 is stable with any capacitive load. This is 1363 AI01 accomplished by sensing the load induced output pole and adding compensation at the amplifier gain node. As the
Layout and Passive Components
capacitive load increases, both the bandwidth and phase The LT1363 amplifier is easy to apply and tolerant of less margin decrease so there will be peaking in the frequency than ideal layouts. For maximum performance (for ex- domain and in the transient response as shown in the ample fast settling time) use a ground plane, short lead typical performance curves.The photo of the small-signal lengths, and RF-quality bypass capacitors (0.01µF to response with 200pF load shows 62% peaking. The large- 0.1µF). For high drive current applications use low ESR signal response with a 10,000pF load shows the output bypass capacitors (1µF to 10µF tantalum). Sockets slew rate being limited to 10V/µs by the short-circuit should be avoided when maximum frequency perfor- current. Coaxial cable can be driven directly, but for best mance is required, although low profile sockets can pulse fidelity a resistor of value equal to the characteristic provide reasonable performance up to 50MHz. For impedance of the cable (i.e., 75Ω) should be placed in more details see Design Note 50. series with the output. The other end of the cable should be terminated with the same value resistor to ground. The response of a cable driver in a gain of 2 driving a 75Ω cable is shown on the front page of the data sheet. 9