lt1460-10 Linear Technology Corporation, lt1460-10 Datasheet - Page 6

• Manufacturer Part Number: lt1460-10
• Description: Micropower Precision Series Reference
• Manufacturer: Linear Technology Corporation

LT1460-10
APPLICATIONS
current step of 1mA or 100 A for R
Figure 2 shows the response of the reference with no load
capacitance.
The reference settles to 10mV (0.1%) in 0.4 s for a 100 A
pulse and to 0.1% in 0.8 s with a 1mA step. When load
capacitance is greater than 0.01 F, the reference begins to
ring due to the pole formed with the output impedance.
6
V
IN
= 12.5V
0.1 F
V
V
V
V
V
V
OUT
OUT
GEN
GEN
OUT
OUT
C
IN
Figure 1. Response Time Test Circuit
Figure 3. C
U
LT1460-10
Figure 2. C
INFORMATION
U
10 s/DIV
2 s/DIV
L
= 0.01 F
V
L
OUT
= 0
W
C
L
L
= 1k or R
R
L
1460-10 F03
1460-10 F02
V
GEN
R
R
10V
9V
R
R
10V
9V
U
L
L
L
L
= 10k
= 1k
= 10k
= 1k
L
= 10k.
1460-10 F01
10V
9V
Figure 3 shows the response of the reference to a 1mA and
100 A load with a 0.01 F load capacitor.
Fast Turn-On
It is recommended to add a 0.1 F or larger input capacitor
to the input pin of the LT1460-10. This helps stability with
large load currents and speeds up turn-on. The LT1460-10
can start in 10 s, but it is important to limit the dv/dt of the
input. Under light load conditions and with a very fast
input, internal nodes overslew and this requires finite
recovery time. Figure 4 shows the result of no bypass
capacitance on the input and no output load. In this case
the supply dv/dt is 12.5V in 30ns which causes internal
overslew, and the output does not bias to 10V until 60 s.
A 0.1 F input capacitor guarantees the part always starts
quickly as shown in Figure 5.
V
V
OUT
V
OUT
V
IN
IN
Figure 5. C
Figure 4. C
20 s/DIV
20 s/DIV
IN
IN
= 0.1 F
= 0
1460-10 F04
1460-5 F04
0V
0V
12.5V
0V
0V
12.5V