BU7485G-TR Datasheet, PDF (26/43 Pages) Rohm – Ground Sense High Speed Low Voltage CMOS Operational Amplifiers

BU7485G BU7485SG BU7486xxx BU7486Sxxx BU7487xx BU7487Sxx ^Datasheet
Application Information
NULL method condition for Test circuit1
Parameter
VDD, VSS, EK, Vicm Unit:V
VF S1 S2 S3 VDD VSS EK Vicm Calculation
Input Offset Voltage
Large Signal Voltage Gain
Common-mode Rejection Ratio
(Input Common-mode Voltage Range)
Power Supply Rejection Ratio
－Calculation－
1. Input Offset Voltage (Vio)
VF1 ON ON OFF 3
0 -1.5 1.8
1
VF2
-0.5
ON ON ON 3
0
0.9
2
VF3
-2.5
VF4
0
ON ON OFF 3
0 -1.5
3
VF5
1.8
VF6
3
ON ON OFF
0 -0.9 0
4
VF7
5.5
|VF1|
Vio =
[V]
1+RF/RS
2. Large Signal Voltage Gain (Av)
Av = 20Log ^{2 × (1+RF/RS)} [dB]
|VF2-VF3|
3. Common-mode Rejection Ratio (CMRR)
4. Power Supply Rejection Ratio (PSRR)
CMRR= 20Log ^{1.8 × (1+RF/RS)} [dB]
|VF4 - VF5|
PSRR = 20Log ^{2.5 × (1+ RF/RS)} [dB]
|VF6 - VF7|
0.1μF
Vicm
SW1
RS=50Ω
Ri=1MΩ
0.015μF _0.015μF
RS=50Ω
Ri=1MΩ
50kΩ
SW2
VDD
DUT
VSS
RF=50kΩ
500kΩ
EK
Vo
500kΩ
SW3
RL
VRL
1000pF
Figure 71. Test circuit 1 (one channel only)
0.01μF
15V
NNUULLLL
-15V
V VF
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TSZ02201-0RAR1G200380-1-2
12.JUL.2013 Rev.001