Datasheet

7
LTC1574
LTC1574-3.3/LTC1574-5
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
APPLICATIO S I FOR ATIO
WUUU
on no-load supply current. Schottky diodes such as
MBR0530, BAS85 and BAT84 work well. Another more
serious effect of the protection diode leakage is that at no
load with nothing to provide a sink for this leakage
current, the output voltage can potentially float above the
maximum allowable tolerance. To prevent this from
occuring, a resistor must be connected between V
OUT
and ground with a value low enough to sink the maximum
possible leakage current.
Low Noise, High Efficiency 3.3V Regulator
TYPICAL APPLICATIO S
U
V
IN
5
100pF
2, 4, 13, 15
6
12
11
7
10
3, 14
50µH
†
0.1µF
6.8nF
22µF*
25V
× 2
1574 TA03
V
OUT
3.3V
450mA
56k
33k
V
IN
4V TO 12.5V
GND
LTC1574
I
PGM
LB
IN
LB
OUT
SHDN
V
FB
SW
* AVX TPSD226K025
** AVX TPSD107K010
†
COILTRONICS CTX50-4
100µF**
10V
× 2
+
+
Dimension in inches (millimeters) unless otherwise noted.
U
PACKAGE DESCRIPTIO
S Package
16-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.016 – 0.050
(0.406 – 1.270)
0.010 – 0.020
(0.254 – 0.508)
× 45°
0
°
– 8
°
TYP
0.008 – 0.010
(0.203 – 0.254)
S16 1098
1
2
3
4
5
6
7
8
0.150 – 0.157**
(3.810 – 3.988)
16
15
14
13
0.386 – 0.394*
(9.804 – 10.008)
0.228 – 0.244
(5.791 – 6.197)
12
11
10
9
DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
*
**
0.053 – 0.069
(1.346 – 1.752)
0.014 – 0.019
(0.355 – 0.483)
TYP
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC