LTC3543 Datasheet, PDF (15/16 Pages) Linear Technology – 600mA Synchronous Step Down Buck Regulator with PLL, Soft-Start and Spread Spectrum

LTC3543
TYPICAL APPLICATIO
Output Noise Spectrum of a
Conventional Buck Switching Converter
(LTC3543 with Spread Spectrum
Disabled) Showing Fundamental and
Harmonic Frequencies
–10 _{RBW = 3kHz}
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
0
6
12
18
24
30
FREQUENCY (MHz)
3543 TA09
Li-Ion
BATTERY
2.7V TO 4.2V
Output Noise Spectrum of the LTC3543
Spread Spectrum Application
V_IN
SW
10µF†
LTC3543
L
3.3µH*
R2
604k
1.5V
C_FWD
10pF
V_OUT
C_OUT ^1.5V
4.7µF**
Spread Spectrum Buck Switching
Converter. Note the Reduction in
Fundamental and Harmonic Peak
Spectral Amplitude Compared
to Conventional Buck Switching
Converter Output Noise
PWR_EN
RUN
V_FB
MODE CAP
GND
EXPOSED
PAD
C1
R1
2.2nF 402k
† muRata GRM40X5R106K1H520
* TDK VLCF5020-3R3N1R6
** TDK TDKC2012X5R0J475MT
3543 TA08
–10 _{RBW = 3kHz}
100
–20
90
–30
80
–40
70
–50
60
–60
50
–70
40
–80
30
–90
20
–100
–110
0
6
12
18
24
30
FREQUENCY (MHz)
10
0
0.1
V_IN = 3.6V
1
10
100
LOAD CURRENT (mA)
1000
3543 TA10
3543 TA11
PACKAGE DESCRIPTIO
DCB Package
6-Lead Plastic DFN (2mm × 3mm)
(Reference LTC DWG # 05-08-1715)
0.70 ±0.05
2.00 ±0.10
(2 SIDES)
R = 0.115
R = 0.05
TYP
TYP
4
0.40 ± 0.10
6
3.55 ±0.05
1.65 ±0.05
(2 SIDES)
2.15 ±0.05
PACKAGE
OUTLINE
0.25 ± 0.05
PIN 1 BAR
TOP MARK
(SEE NOTE 6)
0.50 BSC
1.35 ±0.05
(2 SIDES)
0.200 REF
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
3.00 ±0.10 1.65 ± 0.10
(2 SIDES) (2 SIDES)
0.75 ±0.05
0.00 – 0.05
PIN 1 NOTCH
R0.20 OR 0.25
× 45° CHAMFER
3
1
(DCB6) DFN 0405
0.25 ± 0.05
0.50 BSC
1.35 ±0.10
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (TBD)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
TOP AND BOTTOM OF PACKAGE
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
3543f
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