SC1172 View Datasheet(PDF) - Semtech Corporation
Part Name
Description
Manufacturer
SC1172
Semtech Corporation
SC1172 Datasheet PDF : 12 Pages
| |||
October 25, 1999
MATERIALS LIST
PROGRAMMABLE SYNCHRONOUS DC/DC
CONVERTER WITH LOW DROPOUT
REGULATOR CONTROLLER
SC1172/3
Qty. Reference Part/Description
4 C1,C5,C13,C 0.1µF Ceramic
18
6 C2,C3,C14- 1500µF/6.3V
C17
3 C11,C12, 330µF/6.3V
C21
1 L1
4µH
3 Q1,Q2,Q3 See notes
Vendor
Various
SANYO
Various
See notes
1 R4
1 R5
1 R6
1 R1
1 R12
1 R13
1 R17
1 U1
5mΩ
IRC
2.32kΩ, 1%, 1/8W Various
1kΩ, 1%, 1/8W
Various
10Ω, 5%, 1/8W
Various
1%, 1/8W
Various
1%, 1/8W
Various
100K, 5% 1/8W Various
SC1172/3CSW
SEMTECH
Notes
MV-GX or equiv. Low ESR
8 Turns 16AWG on MICROMETALS T50-52D core
FET selection requires trade-off between efficiency and
cost. Absolute maximum RDS(ON) = 22 mΩ for Q1,Q2
OAR-1 Series
See Table (Not required for SC1172)
See Table (Not required for SC1172)
SETTING LDO OUTPUT VOLTAGE
VO LDO
3.45V
3.30V
3.10V
2.90V
2.80V
2.50V
1.50V
RB
R12
105Ω
105Ω
102Ω
100Ω
100Ω
100Ω
100Ω
RA
R13
182Ω
169Ω
147Ω
130Ω
121Ω
97.6Ω
18.7Ω
VOUT
=
1.265 ⋅ (RA
RB
+ RB )
+ (IFB
⋅RA )
Where :
IFB = Feedback pin bias current
RA = Top feedback resistor
RB = Bottom feedback resistor
See layout diagram for clarification
RA and RB must be low enough so
that the (IFB ⋅ RA ) term does not cause
significant error
© 1999 SEMTECH CORP.
6
652 MITCHELL ROAD NEWBURY PARK CA 91320
Share Link: 