LT1783
APPLICATIONS INFORMATION
Gain
Shutdown
The open-loop gain is almost independent of load when
theoutputissourcingcurrent.Thisoptimizesperformance
in single supply applications where the load is returned to
ground. The typical performance curve of open-loop gain
for various loads shows the details.
The 6-lead part includes a shutdown feature that disables
thepart,reducingquiescentcurrentandmakingtheoutput
high impedance. The part can be shut down by bringing
–
the SHDN pin 1.2V or more above V . When shut down,
the supply current is about 5μA and the output leakage
–
+
current is less than 1μA (V ≤ V
≤ V ). In normal opera-
OUT
–
tion, the SHDN pin can be tied to V or left floating. See
the Typical Performance Characteristics curves, “Supply
Current vs Shutdown Voltage.”
SIMPLIFIED SCHEMATIC
+
V
Q2
Q1
Q3
Q22
D1
D3
SHDN
J1
R1
6k
R2
1k
Q19
Q4
–IN
+IN
Q17
Q18
Q20
+
OUT
Q7
Q8
Q11 Q12
R3
1k
10μA
Q16
Q15
Q9
Q10
Q26
Q13
Q14
Q21
R4
8k
R5
8k
Q25 Q23
Q24
Q5
Q6
D4
D5
–
V
1783 SS
1783fd
12
LINEAR_DIMENSIONS [ Linear Dimensions ]
