The EL5150, EL5151, EL5250, EL5251 and EL5451 are 200MHz bandwidth -3dB voltage mode feedback amplifiers with 0.01% DC accuracy, 1mV offset and 10kV/V open loop gain. These amplifiers are ideal for applications ranging from precision measurement instruments to accelerated video and surveillance applications. Capable of operating a single supply current supplying 1.4mA from 5V to 12V with a dual supply voltage range of ±2.5V to ±5.0V, these amplifiers are also ideal for handheld, portable and battery powered devices. A single amplifier is available in a SOT-23 package and a dual 10 Ld MSOP package suitable for critical board space applications. The quad amplifier is available in a 14 Ld SOIC package. In addition, single and double industry standard 8 Ld SOIC packages are also available. All components operate over an industrial temperature range of -40°C to +85°C.

Product Description

The EL5150, EL5151, EL5250, EL5251 and EL5451 are wide bandwidth, low power, low offset voltage feedback operational amplifiers capable of operating from a single or dual supply. This series of op amps is internally compensated for closed loop gain of +1 or higher. Connected in voltage follower mode, driving a 500 Ω load, this member of the amplifier family exhibits a -3dB bandwidth of approximately 200MHz. Loading is set to suit typical video applications, with a 150Ω load and gain set to +2, the bandwidth is reduced to about 40MHz, and the 67V/µs slew rate. Shutting down the EL5151 and EL5251 pins reduces the already low power requirements of this amplifier when the amplifier is disabled, typically 12µA.

Input, output and supply voltage ranges

The EL5150 and family members are designed for a supply voltage range of 5V to 12V. The supply voltage range is ±2.5V to ±5V for separate power supply. Of course, split supply operations can easily be achieved using a single consumable by splitting the single halves to provide a simple voltage divider.

Input common mode range

These amplifiers have an input common-mode voltage from the negative supply (VS- pin) to 3.5V above the positive supply (VS+ pin) to 3.5V. If the input signal is outside this range, the output signal will appear distorted.

Maximum output swing and load resistance

Product demonstration of the EL5150 and family members For VS = ±5V, the maximum output swing range is -4V to 4V with a load resistance of 500Ω. Of course, as the load resistance gets lower, the output swing decreases accordingly; for example, if the load resistance is 150Ω, then the output swing will range from -3.5V to 3.5V. This response is a simple application of Ohm's law, showing that lower values of resistance result in greater current demands on the amplifier. Additionally, the load resistance affects the frequency response of this family as well as all operational amplifiers; as the gain versus frequency shows, the various RL curves clearly show. In the case where the frequency response decreases as the bandwidth load resistance is a function of the load resistance there is an output zero response of the amplifier.

Select Feedback Resistor

A feedback resistor is required to achieve unity gain; just short the output pin to the inverting input pin. Getting bigger +1 requires a feedback and gain resistor to set the desired gain. This is interesting because the feedback resistance forms a pole-inverting input with the parasitic capacitance; as the feedback resistance increases, the position of the pole moves in the frequency domain, and the phase margin of the amplifier decreases and becomes less stable. Peaks ringing in the frequency domain and in the time domain are symptomatic pole locations for this transition. So we want to keep the feedback resistor as small as possible. You may want to use a lot of feedback resistors for some reason; in this case, a small capacitor Pico Farad range in parallel with the feedback resistor to compensate for very few transitions and maintain stability is recommended. For gains greater than 1, a feedback resistor ranging from 500 Ω to 750 Ω has been determined to respond optimally.