LT1301I LINER [Linear Technology], LT1301I Datasheet - Page 7

• Manufacturer Part Number: LT1301I
• Description: Micropower High Efficiency 5V/12V Step-Up DC/DC Converter for Flash Memory
• Manufacturer: LINER [Linear Technology]

APPLICATIONS
switching. Zero load current causes the LT1301 to switch
so infrequently that C3 can completely discharge reducing
subsequent peak switch current to 400mA. If a load is
suddenly applied, output voltage will sag until C3 can be
recharged and peak switch current returns to 1A.
If the full capacity of the LT1301 is not required peak
current can be reduced by changing the value of R3 as
shown in Figure 8. With R3 = 0 switch current is limited to
approximately 400mA. Smaller, less expensive inductors
with lower saturation ratings can then be used.
Inductor Selection
For full output power, the inductor should have a satura-
tion current rating of 1.25A for worst-case current limit,
although it is acceptable to bias an inductor 20% or more
into saturation. Smaller inductors can be used in conjunc-
tion with the I
inductor DCR. For best efficiency limit the DCR to 0.03
or less. Toroidal types are preferred in some cases due to
their inherent flux containment and EMI/RFI superiority.
Recommended inductors are listed in Table 1.
Table 1. Recommended Inductors
PART NUMBER
DO3316-333
DO1608-223
DO1608-103
CTX20-1
GA10-332
LQH3G220K04M00 Murata-Erie
CD73-330KC
CDRH62-330MC
LIM
pin. Efficiency is significantly affected by
Coiltronics
Gowanda
VENDOR
Coilcraft
Coilcraft
Coilcraft
Sumida
Sumida
U
INFORMATION
U
L ( H) DCR ( ) V
33
22
10
20
33
22
33
33
W
0.088
0.131
.175
.077
0.48
.31
.11
0.7
IN
3.3
3.3
3.3
3.3
3.3
3.3
3.3
3.3
5
5
5
2
5
5
5
5
5
(V)
U
I
Open
Open
Open
Ground
10k
Ground
Open
Open
Open
Open
Open
Ground
Ground
Open
Open
Open
Ground
Open
Ground
LIM
PIN
Table 2. Recommended Capacitors
VENDOR
AVX
Sanyo
Panasonic
30mA
Figure 8. Peak Switch Current vs. Current Limit Set Resistor
84
89
82
85
86
88
78
84
88
86
89
81
85
84
88
80
85
84
83
EFFICIENCY (%)
60mA
1100
1000
900
800
700
600
500
400
300
84
89
82
—
87
—
—
84
88
86
89
—
—
85
88
80
—
84
—
100
1.6V V
SERIES
TPS
OS-CON
HFQ
120mA
CURRENT LIMIT SET RESISTOR ( )
85
90
—
—
—
—
—
—
89
87
90
—
—
86
89
81
—
85
—
IN
1k
5V
Surface Mount
10k
HEIGHT (mm)
Through-Hole
Through-Hole
COMPONENT
Through-Hole
TYPE
5.5
3.5
3.5
4.2
2.0
3.5
3.0
100k
LT1301 F8
1M
PHONE#
(803)448–9411
(619) 661–6835
[phone]
PHONE NUMBER
(708) 639–6400
LT1301
[phone]
[phone]
[phone]
[phone]
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