LT1109 Linear Technology, LT1109 Datasheet

no-image

LT1109

Manufacturer Part Number
LT1109
Description
Micropower Low Cost DC/DC Converter Adjustable and Fixed 5V/ 12V
Manufacturer
Linear Technology
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
LT1109
Manufacturer:
LT
Quantity:
20 000
Part Number:
LT1109A1
Manufacturer:
MOT
Quantity:
86
Part Number:
LT1109A1
Manufacturer:
LINEAR/凌特
Quantity:
20 000
Part Number:
LT1109A1CS8
Manufacturer:
TI/德州仪器
Quantity:
20 000
Part Number:
LT1109ACF-12
Manufacturer:
FAI
Quantity:
1 900
Part Number:
LT1109ACN8
Manufacturer:
LT
Quantity:
5 510
Part Number:
LT1109ACN8
Manufacturer:
LT
Quantity:
5 510
Part Number:
LT1109ACN8
Manufacturer:
LT
Quantity:
1 000
Part Number:
LT1109ACN8
Manufacturer:
LT/凌特
Quantity:
20 000
Part Number:
LT1109ACN8-12
Manufacturer:
LT
Quantity:
1 308
Part Number:
LT1109ACN8-12
Manufacturer:
LT
Quantity:
20 000
Part Number:
LT1109ACN8-12#PBF
Quantity:
45
Part Number:
LT1109ACS8
Manufacturer:
LT
Quantity:
2 249
Company:
Part Number:
LT1109ACS8-12
Quantity:
2 200
* 8-PIN PACKAGE ONLY
MURATA-ERIE LQH4N330K (I
**C1 = MATSUO 267M1602226 OR EQUIVALENT
A
SHUTDOWN
FEATURE
TYPICAL
L1 = SUMIDA CD54-330LC (I
PPLICATI
Flash Memory VPP Generators
3V to 5V Converters
5V to 12V Converters
Disk Drives
PC Plug-In Cards
Peripherals
Battery-Powered Equipment
Uses Off-the-Shelf Inductors
Only 33 H Inductor Required
Low Cost
3-Lead TO-92, SO8, or 8-Pin DIP
Adjustable or Fixed 5V or 12V Output
120kHz Oscillator
Only Three External Components Required
320 A I
1.6V Minimum Start-Up Voltage
Logic Controlled Shutdown
V
5V
IN
COILTRONICS CTX33-1 (80mA)
ISI LCS2414-330K (I
Flash Memory VPP Generator
PROGRAM
Q
All Surface Mount
1
7
33 H
L1
S
A
V
SHUTDOWN*
IN
LT1109CS8-12
O
PPLICATI
OUT
GND
OUT
U
SW
= 50mA)
3
4
S
= 80mA)
SENSE
MBRS120T3
OUT
= 50mA)
8
+
O
LT1109 • TA01
U
C1**
22 F
16V
V
12V
80mA
OUT
15
12
9
6
3
0
0
10
20 30 40 50 60 70 80 90
Adjustable and Fixed 5V, 12V
OUTPUT CURRENT (mA)
Output Voltage
D
The LT1109 is a simple step-up DC/DC converter. Avail-
able in 8-pin SO, 3-lead TO-92 (fixed output only) or
miniDIP packages, the devices require only three external
components to construct a complete DC/DC converter.
Current drain is just 320 A at no load, making the device
ideal for cost-sensitive applications where standby cur-
rent must be kept to a minimum.
The LT1109-5 can deliver 5V at 100mA from a 3V input
and the LT1109-12 can deliver 12V at 60mA from a 5V
input. The 8-pin versions also feature a logic controlled
SHUTDOWN pin that turns off the oscillator when taken
low. The gated-oscillator design requires no frequency
compensation components. The high frequency 120kHz
oscillator permits the use of small surface mount induc-
tors and capacitors. For a 5V to 12V at 120mA converter,
see the LT1109A. Foa a 5V to 12V at 200mA converter
with 20 A shutdown current, see the LT1301.
ESCRIPTIO
V
IN
Micropower Low Cost
= 5V
LT1109 • TPC01
100
DC/DC Converter
U
SHUTDOWN
5V/DIV
5V/DIV
V
OUT
OV
Flash Memory Program Output
1ms/DIV
LT1109
LT1109 • TA02
1

Related parts for LT1109

LT1109 Summary of contents

Page 1

... The gated-oscillator design requires no frequency compensation components. The high frequency 120kHz oscillator permits the use of small surface mount induc- tors and capacitors. For 12V at 120mA converter, see the LT1109A. Foa 12V at 200mA converter with 20 A shutdown current, see the LT1301. U Output Voltage ...

Page 2

... LT1109 • PO103 T = 100 C, = 150 C/W JMAX JA S8 PART ORDER PART NUMBER MARKING LT1109CS8 1109 LT1109CS8-5 10905 LT1109CS8-12 10912 (LT1109CN8, LT1109CS8), unless otherwise specified CONDITIONS Switch Off LT1109 LT1109- LT1109-12 12V IN LT1109 LT1109-5 LT1109-12 Full Load I = 500mA ...

Page 3

... TEMPERATURE (°C) LT1109 • TPC05 (LT1109CN8, LT1109CS8), unless otherwise specified CONDITIONS V = 12V SW N8, S8 Package N8, S8 Package N8, S8 Package SHUTDOWN N8, S8 Package SHUTDOWN CE C HARA TERISTICS C Oscillator Frequency ...

Page 4

... GND LT1109-12 29k U LT1109Z OPER ATIO The LT1109Z-5 and LT1109Z-12 are fixed output voltage step-up DC/DC converters in a 3-pin TO-92 package. Power for internal regulator circuitry is taken from the V pin, a technique known as “bootstrapping.” Circuit OUT operation can be best understood by referring to the block diagram ...

Page 5

... L can be used. These equations assume that inductor current is zero. This situation is called “discon- tinuous mode operation” in switching regulator parlance. Setting “t” to the switch-ON time from the LT1109 speci- fication table (typically 4.2 s) will yield I “L” and the end of the switch-ON time can be calculated as ...

Page 6

... Although they are rated at 1A, the switching time of a 1N4001 is in the 10 s-50 s range. At best, efficiency will be severely compromised when these diodes are used; at worst, the circuit may not work at all. Most LT1109 circuits will be well served by a 1N5818 Schottky diode. The combination of 500mV forward drop at 1A current, fast ...

Page 7

... CELLS + 10 F 20V 10k VN2222 LT1109 • TA05 12V 40mA AT 3V INPUT 15mA AT 2V INPUT 2 CELLS 10 F 20V LT1109 • TA07 LT1109 Converter 22 H CADDELL-BURNS 1N5818 7120-17 5V 100mA AT 3V INPUT 20mA AT 2V INPUT SW V OUT LT1109CZ 16V GND LT1109 • ...

Page 8

... LT1109 PACKAGE DESCRIPTIO 0.300 – 0.320 (7.620 – 8.128) 0.065 (1.651) 0.009 – 0.015 TYP (0.229 – 0.381) +0.025 0.045 ± 0.015 0.325 –0.015 (1.143 ± 0.381) +0.635 8.255 –0.381 0.100 ± 0.010 (2.540 ± 0.254) 0.010 – 0.020 45 (0.254 – ...

Related keywords