LT1185
UU W U
APPLICATIO S I FOR ATIO
5V Logic, Positive Regulated Output
+
+ VOUT
5V
RLIM†
R1
4k
*
REF
GND
+
FB
Q1
2N3906
VIN
LT1185
R2
R5
300k
VOUT
VIN
R7
R6
2.4k† 30k
–
LT1185 • F3a
*CMOS LOGIC
†FOR HIGHER VALUES OF RLIM, MAKE R7 = (RLIM)(0.6)
5V Logic, Negative Regulated Output
5V
VIN –
“HI” = OUTPUT “OFF”
3 EA 1N4148
Q1
2N3906
R4
33k
RLIM
REF
GND
FB
VIN
LT1185
VOUT
LT1185 • F03b
Figure 3. Shutdown Techniques
10