CS3001

CS3002

8

DS490F9

3. CS3001/CS3002 OVERVIEW

The CS3001/CS3002 amplifiers are designed for

precision measurement of signals from DC to

2 kHz when operating from a supply voltage of

+2.7 V to +6.7 V (

± 1.35 to ± 3.35 V). The ampli-

fiers are designed with a patented architecture that

utilizes multiple amplifier stages to yield very high

open loop gain at frequencies of 10 kHz and below.

The amplifiers yield low noise and low offset drift

while consuming relatively low supply current. An

increase in noise floor above 2 kHz is the result of

intermediate stages of the amplifier being operated

at very low currents. The amplifiers are intended

for amplifying small signals with large gains in ap-

plications where the output of the amplifier can be

band-limited to frequencies below 2 kHz.

3.1

Open-loop Gain and Phase

Response

Figure 15 illustrates the open loop gain and phase

response of the CS3001/CS3002. The gain slope of

the amplifier is about –100 dB/decade between

500 Hz and 60 kHz and transitions to –20 dB/de-

cade between 60 kHz and its unity gain crossover

frequency at about 4.8 MHz. Phase margin at unity

gain is about 70 degrees; gain margin is about

20 dB.

-360

-315

-270

-225

-180

-135

-90

-45

10K

100K

1M

10M

0

20

40

60

80

100

-100 dB/ dec

-20 dB/ dec

Figure 15. CS3001/CS3002 Open-loop Gain and Phase Response