LPC660IN National Semiconductor, LPC660IN Datasheet - Page 12

• Manufacturer Part Number: LPC660IN
• Description: IC OPAMP LOW PWR CMOS QUAD 14DIP
• Manufacturer: National Semiconductor

Specifications of LPC660IN

• Amplifier Type: General Purpose
• Number Of Circuits: 4
• Output Type: Rail-to-Rail
• Slew Rate: 0.11 V/µs
• Gain Bandwidth Product: 350kHz
• Current - Input Bias: 0.002pA
• Voltage - Input Offset: 1000µV
• Current - Supply: 160µA
• Current - Output / Channel: 40mA
• Voltage - Supply, Single/dual (±): 4.75 V ~ 15.5 V, ±2.38 V ~ 7.75 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 14-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• -3db Bandwidth: -
• Other names: *LPC660IN

www.national.com
Application Hints
(Input pins are lifted out of PC board and soldered directly to components.
All other pins connected to PC board.)
BIAS CURRENT TESTING
The test method of Figure 7 is appropriate for bench-testing
bias current with reasonable accuracy. To understand its
operation, first close switch S2 momentarily. When S2 is
opened, then
A suitable capacitor for C2 would be a 5 pF or 10 pF silver
mica, NPO ceramic, or air-dielectric. When determining the
magnitude of I
FIGURE 7. Simple Input Bias Current Test Circuit
−
, the leakage of the capacitor and socket
FIGURE 6. Air Wiring
(Continued)
01054725
01054724
12
must be taken into account. Switch S2 should be left shorted
most of the time, or else the dielectric absorption of the
capacitor C2 could cause errors.
Similarly, if S1 is shorted momentarily (while leaving S2
shorted)
where C
Typical Single-Supply Applications
Note: A 5V bias on the photodiode can cut its capacitance by a factor of 2
or 3, leading to improved response and lower noise. However, this bias on
the photodiode will cause photodiode leakage (also known as its dark
current).
Note: (Upper limit of output range dictated by input common-mode range;
lower limit dictated by minimum current requirement of LM385.)
(V
+
= 5.0 V
Photodiode Current-to-Voltage Converter
x
is the stray capacitance at the + input.
DC
Micropower Current Source
)
01054718
01054717