Datasheet
Table Of Contents
- 1.0 Electrical Characteristics
- 2.0 Typical Performance Curves
- FIGURE 2-1: Input Offset Voltage at VDD = 5.5V.
- FIGURE 2-2: Input Offset Voltage at VDD = 2.3V.
- FIGURE 2-3: Input Bias Current at VDD = 5.5V.
- FIGURE 2-4: Input Offset Voltage Drift at VDD = 5.5V.
- FIGURE 2-5: Input Offset Voltage Drift at VDD = 2.3V.
- FIGURE 2-6: Input Offset Current at VDD = 5.5V.
- FIGURE 2-7: Input Offset Voltage vs. Ambient Temperature.
- FIGURE 2-8: Quiescent Current vs. Ambient Temperature.
- FIGURE 2-9: Maximum Output Voltage Swing vs. Ambient Temperature at RL = 5 kW.
- FIGURE 2-10: Input Bias, Offset Currents vs. Ambient Temperature.
- FIGURE 2-11: CMRR, PSRR vs. Ambient Temperature.
- FIGURE 2-12: Maximum Output Voltage Swing vs. Ambient Temperature at RL = 25 kW.
- FIGURE 2-13: Output Short Circuit Current vs. Ambient Temperature.
- FIGURE 2-14: Slew Rate vs. Ambient Temperature.
- FIGURE 2-15: Input Bias, Offset Currents vs. Common Mode Input Voltage.
- FIGURE 2-16: Gain Bandwidth Product, Phase Margin vs. Ambient Temperature.
- FIGURE 2-17: Input Offset Voltage vs. Common Mode Input Voltage.
- FIGURE 2-18: Input Offset Voltage vs. Output Voltage.
- FIGURE 2-19: Quiescent Current vs. Power Supply Voltage.
- FIGURE 2-20: DC Open-Loop Gain vs. Load Resistance.
- FIGURE 2-21: Gain-Bandwidth Product, Phase Margin vs. Load Resistance.
- FIGURE 2-22: Output Voltage Headroom vs. Output Current Magnitude.
- FIGURE 2-23: DC Open-Loop Gain vs. Power Supply Voltage.
- FIGURE 2-24: Channel-to-Channel Separation vs. Frequency (MCP617 and MCP619 only).
- FIGURE 2-25: Open-Loop Gain, Phase vs. Frequency.
- FIGURE 2-26: Input Noise Voltage, Current Densities vs. Frequency.
- FIGURE 2-27: Small-Signal, Non-Inverting Pulse Response.
- FIGURE 2-28: CMRR, PSRR vs. Frequency.
- FIGURE 2-29: Maximum Output Voltage Swing vs. Frequency.
- FIGURE 2-30: Small-Signal, Inverting Pulse Response.
- FIGURE 2-31: Large-Signal, Non-Inverting Pulse Response.
- FIGURE 2-32: Chip Select (CS) to Amplifier Output Response Time (MCP618 only).
- FIGURE 2-33: The MCP616/7/8/9 Show No Phase Reversal.
- FIGURE 2-34: Large-Signal, Inverting Pulse Response.
- FIGURE 2-35: Chip Select (CS) Internal Hysteresis (MCP618 only).
- FIGURE 2-36: Measured Input Current vs. Input Voltage (below VSS).
- 3.0 Pin Descriptions
- 4.0 Applications Information
- 5.0 Design Aids
- 6.0 Packaging Information
© 2008 Microchip Technology Inc. DS21613C-page 19
MCP616/7/8/9
4.9.3 THREE OP AMP
INSTRUMENTATION AMPLIFIER
A classic, three-op amp instrumentation amplifier is
illustrated in Figure 4-11. The two-input op amps
provide differential signal gain and a common mode
gain of +1. The output op amp is a difference amplifier,
which converts its input signal from differential to a
single-ended output; it rejects common mode signals at
its input. The gain of this circuit is simply adjusted with
one resistor (R
G
). The reference voltage (V
REF
) is
typically referenced to mid-supply (V
DD
/2) in single-
supply applications.
FIGURE 4-11: Three-Op Amp
Instrumentation Amplifier.
4.9.4 PRECISION GAIN WITH GOOD
LOAD ISOLATION
In Figure 4-12, the MCP616 op amp, R
1
and R
2
provide
a high gain to the input signal (V
IN
). The MCP616’s low
offset voltage makes this an accurate circuit.
The MCP606 is configured as a unity-gain buffer. It
isolates the MCP616’s output from the load, increasing
the high gain stage’s precision. Since the MCP606 has
a higher output current, and the two amplifiers are
housed in separate packages, there is minimal change
in the MCP616’s offset voltage due to loading effect.
FIGURE 4-12: Precision Gain with Good
Load Isolation.
V
OUT
V
1
V
2
–()1
2R
2
R
G
---------+
⎝⎠
⎜⎟
⎛⎞
R
4
R
3
------
⎝⎠
⎜⎟
⎛⎞
V
REF
+=
R
2
MCP617
V
REF
V
1
½
R
4
R
3
MCP616
R
2
R
G
MCP617
V
OUT
V
2
½
R
4
R
3
V
OUT
V
IN
1R
2
R
1
⁄
+()=
R
2
R
1
MCP616
V
OUT
V
IN
MCP606