DC833A - Schematic

*
L1
1
JP6
Boost
Ext
2
3
10uH
Rsw
1M
4
**
Vin
Cin
4.7uF
6.3V
On
Off
E3
3
GND
*
+ Cin1
68uF
10V
1
E1
1
Vin
2
Vin
JP5
Vout Enable
2
6
*
Rsd
10M
U1
LTC3026EDD
SW
VOUT
9
VOUT
10
FB
SHDN
BST
GND
5
3
***
JP1
0.8V
Rpg
100k
11
JP3
1.5V
JP4
1.8V
R2
R3
R4
R5
4.02k
4.02k
3.01k
3.01k
8
PG 7
GND
JP2
1.2V
R6
0
Cout
10uF
4V
E2
Cout1
opt.
GND
E4
R1
4.02k
E7
**
Vboost
*
**
***
GND
Pgood
Cboost
4.7uF
6.3V
E5
Vout
1.5A(max)
E6
Cin1 is an optional capacitor. It is inserted on the DC833 to dampen the (possible) ringing voltage
due to the use of long input leads. On a normal, typical PCB, with the short traces, Cin1 is not needed.
Also, Rsw and Rsd are optional parts on the DC833. They're inserted in case the jumper shunts
accidently fall out.
1.14V is the minimum input voltage that the LTC3026 will operate at. The minimum input voltage for a
specific regulator circuit depends on the output voltage (plus the dropout voltage).
3.5V is the maximum input voltage with the internal boost converter enabled. With an external voltage
supply on the boost pin, the maximum input voltage is 5.5V. See the table below.
JP6
Vin
Vboost
Ext
1.14V-5.5V
4.5V-5.5V
Boost
1.14V-3.5V
The maximum output voltage is 2.6V.
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
CONTRACT NO.
APPROVALS
DRAWN
June Wu
DATE
9/29/04
CHECKED
TECHNOLOGY
TITLE
LTC3026EDD, Low Input Voltage VLDO Linear Regulator
APPROVED
ENGINEER
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
Tom Gross
9/24/04
DESIGNER
Tuesday, February 08, 2005
SIZE CAGE CODE
SCALE:
FILENAME:
DWG NO
REV
A
DC833A
SHEET
1
OF
1