BU7251G Datasheet, PDF (12/19 Pages) Rohm – Comparators: Low Voltage CMOS

BU7251G,BU7251SG, BU7231G,BU7231SG,
BU7252F/FVM,BU7252S F/FVM,BU7232F/FVM,BU7232S F/FVM
●Schematic diagram
Technical Note
Fig. 89 Simplified schematic
●Test circuit1 NULL method
VDD,VSS,EK,Vicm, Unit : [V]
Parameter
VF
S1
S2
S3
VDD VSS EK Vicm ^Calculation
Input offset voltage
VF1
ON
ON
OFF
3
0 -0.1 0.3
1
Large signal voltage gain
VF2
ON
ON
ON
3
0 ^-0.3 0.3
2
VF3
-2.7
Common-mode rejection ratio
(Input common-mode voltage range)
VF4
VF5
ON
ON
OFF
3
0
-0.1
0
3
3
Power supply rejection ratio
VF6
VF7
ON
ON
OFF
1.8
5.5
0 -0.1 0.3
4
-Calculation-
1. Input offset Voltage (Vio)
|VF1|
Vio =
[V]
1+Rf/Rs
2. Large signal voltage gain (Av)
3. Common-mode rejection ratio (CMRR)
4. Power supply rejection ratio (PSRR)
0.47[μF]
S1
0.1[uF]
RS_＝ 50[Ω]
Vicm
Ri_＝ 1[MΩ]
Ri_＝ 1[MΩ]
RS_＝50[Ω] _0.1[uF]
VDD
DUT
VSS
S2
50[kΩ]
Rf
50[kΩ]
EK
RK
500[kΩ]
500[kΩ]
RK
0.01[μF]
+15[V]
NULL
S3
-15[V]
VF
RL
Fig. 90 Test Circuit 1 (one channel only)
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