LTC3538
13
3538fb
V
OUT
R1
1V
FB
C
P2
C
P1
RZ
V
C
R2
C
Z1
3538 F05
+
1
2
Figure 5. Error Amplifi er with Type III Compensation
OPERATION
Most applications demand an improved transient response
to allow a smaller output fi lter capacitor. To achieve a higher
bandwidth, Type III compensation is required, providing
two zeros to compensate for the double-pole response of
the output fi lter. Referring to Figure 5, the location of the
poles and zeros are given by:
ƒ
POLE1
1
2 π 32e
3
R1C
P1
Hz
(which is extremly close to DC)
ƒ
ZERO1
=
1
2 π R
Z
C
P1
Hz
ƒ
ZERO2
=
1
2 π R1C
Z1
Hz
ƒ
POLE2
=
1
2 π R
Z
C
P2
Hz
where resistance is in Ohms and capacitance is in
Farads.
LTC3538
14
3538fb
SW1
R2
200k
M1
R1
806k
10k
15k
C
IN
10μF
C
IN
: TAIYO YUDEN JMK212BJ106MG
C
OUT
: TAIYO YUDEN JMK325BJ226MM
L1: SUMIDA CDRH2D18/HP-3R3NC
M1:
μP OPEN DRAIN I/O OR FAIRCHILD FDV301N
V
IN
BURST
SW2
LTC3538
USB
4.35V TO 5.25V
L1
3.3
μH
GND
V
OUT
FB
V
C
V
OUT
5V, 500mA
C
OUT
22μF
330pF
33pF
PWM BURST
3538 TA03
ON OFF
TYPICAL APPLICATION
High Effi ciency 5V/500mA from USB Input
LTC3538
15
3538fb
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.
PACKAGE DESCRIPTION
3.00 ±0.10
(2 SIDES)
2.00 ±0.10
(2 SIDES)
NOTE:
1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE
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
0.40 ± 0.10
BOTTOM VIEW—EXPOSED PAD
0.75 ±0.05
R = 0.115
TYP
R = 0.05
TYP
1.35 REF
1
4
85
PIN 1 BAR
TOP MARK
(SEE NOTE 6)
0.200 REF
0.00 – 0.05
(DCB8) DFN 0106 REV A
0.23 ± 0.05
0.45 BSC
PIN 1 NOTCH
R = 0.20 OR 0.25
× 45° CHAMFER
0.25 ± 0.05
1.35 REF
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED
2.10 ±0.05
0.70 ±0.05
3.50 ±0.05
PACKAGE
OUTLINE
0.45 BSC
1.35 ±0.10
1.35 ±0.05
1.65 ± 0.10
1.65 ± 0.05
DCB Package
8-Lead Plastic DFN (2mm × 3mm)
(Reference LTC DWG # 05-08-1718 Rev A)

LTC3538EDCB#TRMPBF

Mfr. #:
Manufacturer:
Analog Devices / Linear Technology
Description:
Switching Voltage Regulators 800mA, 1MHz Wide Input Voltage Synch Buck-Boost DC/DC Converter in DFN-8
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet