LTC1143LCS-ADJ#PBF Linear Technology, LTC1143LCS-ADJ#PBF Datasheet

no-image

LTC1143LCS-ADJ#PBF

Manufacturer Part Number
LTC1143LCS-ADJ#PBF
Description
IC SW REG STEP-DOWN DUAL 16-SOIC
Manufacturer
Linear Technology
Type
Step-Down (Buck)r
Datasheet

Specifications of LTC1143LCS-ADJ#PBF

Internal Switch(s)
No
Synchronous Rectifier
No
Number Of Outputs
2
Voltage - Output
Adjustable
Current - Output
50mA
Frequency - Switching
400kHz
Voltage - Input
3.5 ~ 16 V
Operating Temperature
0°C ~ 70°C
Mounting Type
Surface Mount
Package / Case
16-SOIC (3.9mm Width)
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Power - Output
-
APPLICATIONS
FEATURES
TYPICAL
3.3V/2A
High Efficiency Maintained over Three Decades of
Dual Outputs
Very High Efficiency: Over 95% Possible
Current Mode Operation for Excellent Line and Load
Transient Response
Output Current
Low Standby Current at Light Loads: 160 A/Output
Logic-Controlled Shutdown (LTC1143, LTC1143L)
Wide V
(LTC1143L, LTC1143L-ADJ)
Very Low Dropout Operation: 100% Duty Cycle
Available in Narrow 16-Pin SO Package
Personal Digital Assistants
Notebook and Palmtop Computers
Battery-Operated Digital Devices
Portable Instruments
DC Power Distribution Systems
V
C
220 F
L1, L2: SUMIDA CDRH125-270
P1: SILICONIX Si4953DY/FAIRCHILD NDS8947
R
OUT1
OUT1
SENSE1,
10V
LTC1143, LTC1143L: 3.3V, 5V
LTC1143L-ADJ: Dual Adjustable
2
49.9k
R
R
+
IN
SENSE2
0.05
1%
SENSE1
R1
Range: 3.5V to 16V
APPLICATION
: DALE WSL-2010-.05
R2
82.5k
1%
27 H
+
U
L1
100pF
C
22 F
25V
IN1
2
P1A
1000pF
D1
MBRS320T3
0.22 F
U
16
4
1
2
Figure 1. High Efficiency Dual 3.3V/2.5V Regulator
P-DRIVE 1
SENSE
SENSE
V
FB1
GND1
V
IN1
13
300pF
3
+
C
1
1
T1
C
T1
14
I
TH1
15
R
1k
C1
C
3300pF
LTC1143L-ADJ
C1
4V TO 14V
Step-Down Switching Regulator
V
IN
3300pF
DESCRIPTION
The LTC1143 series is a dual step-down switching regulator
controller featuring automatic Burst Mode
maintain high efficiencies at low output currents. This
device is composed of two separate regulator blocks,
each driving an external power MOSFET at switching
frequencies up to 400kHz using a constant off-time current
mode architecture. Both fixed and adjustable voltages are
available.
The operating current level for both regulators is user-
programmable via an external current sense resistor.
Wide input supply range allows operation from 4V to 14V
(16V maximum). The LTC1143L and LTC1143L-ADJ
extend operation to V
low dropout regulation limited only by the R
external MOSFET and resistance of the inductor and
current sense resistor.
The LTC1143 series is ideal for applications requiring dual
output voltages with high conversion efficiencies over a
wide load current range in a small amount of board space.
Burst Mode is a trademark of Linear Technology Corporation.
C
C2
, LTC and LT are registered trademarks of Linear Technology Corporation.
I
TH2
7
R
1k
Dual High Efficiency SO-16
C2
C
T2
6
C
300pF
P-DRIVE 2
T2
SENSE
SENSE
GND2
5
V
IN2
V
11
FB2
+
2
2
U
9
8
10
12
MBRS320T3
IN
LTC1143/LTC1143L
0.22 F
= 3.5V. 100% duty cycle provides
1000pF
D2
P1B
LTC1143L-ADJ
100pF
27 H
L2
+
49.9k
Controllers
1%
R4
C
22 F
25V
IN2
R
2
0.05
SENSE2
R3
49.9k
1%
TM
DS(ON)
operation to
+
1143 F01
C
220 F
10V
V
2.5V/2A
OUT2
2
OUT2
of the
1

Related parts for LTC1143LCS-ADJ#PBF

LTC1143LCS-ADJ#PBF Summary of contents

Page 1

... The LTC1143 series is ideal for applications requiring dual output voltages with high conversion efficiencies over a wide load current range in a small amount of board space. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation ...

Page 2

... V = 2.1V, 3.5V < V < 12V 3.5V < V < 12V IN 3.5V < V < 12V, V 3.3V IN OUT ORDER PART TOP VIEW NUMBER – SENSE TH1 LTC1143LCS-ADJ IN1 5 12 P-DRIVE GND2 FB2 + 8 9 SENSE 2 S PACKAGE 16-LEAD PLASTIC SO = 125 C/W JA MIN TYP 1.21 1.25 0.2 3.23 3 ...

Page 3

ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER Current Sense Threshold Voltage LTC1143/LTC1143L 8 9 LTC1143L-ADJ Shutdown Pin Threshold 2 10 LTC1143/LTC1143L Shutdown Pin Input Current 2 10 LTC1143/LTC1143L ...

Page 4

LTC1143/LTC1143L LTC1143L-ADJ W U TYPICAL PERFORMANCE CHARACTERISTICS 5V Output Efficiency 100 10V 100 1000 LOAD CURRENT (mA) LTC1143 G01 3.3V Efficiency vs Input Voltage 100 ...

Page 5

W U TYPICAL PERFORMANCE CHARACTERISTICS Gate Charge Supply Current 100nC 29nC 200 260 140 OPERATING FREQUENCY (kHz) LTC1143 G10 PIN FUNCTIONS ...

Page 6

LTC1143/LTC1143L LTC1143L-ADJ PIN FUNCTIONS V (Pin 13): Supply Pin, 3.3V Section. Must be closely IN3 decoupled to 3.3V power ground Pin 3. C (Pin 14): External capacitor sets the operating frequency for the 3.3V ...

Page 7

U U FUNCTIONAL DIAGRA Only one regulator block shown. Connections shown for LT1143/LTC1143L; changes create LTC1143L-ADJ SLEEP – – V TH1 V TH2 T + OFF-TIME 14(6) CONTROL OPERATION Refer to Functional Diagram and ...

Page 8

LTC1143/LTC1143L LTC1143L-ADJ U OPERATION Refer to Functional Diagram and Figure 1 The circuit now enters sleep mode with the power MOSFET turned off. In sleep mode a majority of the circuitry is turned off, dropping the quiescent current from 1.6mA ...

Page 9

U U APPLICATIONS INFORMATION 0.20 0.15 0.10 0. MAXIMUM OUTPUT CURRENT (A) Figure 2. Selecting R The load current below which Burst Mode operation commences and the peak short circuit current, BURST I ...

Page 10

LTC1143/LTC1143L LTC1143L-ADJ U U APPLICATIONS INFORMATION Once the frequency has been set chosen to provide no more than 25mV/R to-peak inductor ripple current. This results in a minimum required inductor value of 5.1(10 )(R ...

Page 11

U U APPLICATIONS INFORMATION but = 0.005/ C can be used as an approximation for low voltage MOSFETs. When selecting the P-channel power MOSFET for each section, consideration should be given to using a dual MOSFET with the other half ...

Page 12

LTC1143/LTC1143L LTC1143L-ADJ U U APPLICATIONS INFORMATION Aluminum electrolytic and dry tantalum capacitors are both available in surface mount configurations. In the case of tantalum it is critical that the capacitors are surge tested for use in switching power supplies. An ...

Page 13

U U APPLICATIONS INFORMATION drawn from V , the resulting loss increases with IN input voltage. For V = 10V the DC bias losses are IN generally less than 1% for load currents over 30mA. However at very low load ...

Page 14

LTC1143/LTC1143L LTC1143L-ADJ U U APPLICATIONS INFORMATION The LTC1143L-ADJ outputs can be turned off in one of two ways placing a power MOSFET switch in the V to the entire regulator pulling the V 1.4V, which ...

Page 15

U U APPLICATIONS INFORMATION (a) CONTINUOUS MODE OPERATION (b) Burst Mode OPERATION Figure 7. C Waveforms T Auxiliary Windings––Suppressing Burst Mode Operation The LTC1143 series operates nonsynchronously with the normal limitation that the power drawn from the inductor primary winding ...

Page 16

LTC1143/LTC1143L LTC1143L-ADJ U U APPLICATIONS INFORMATION 5) Is the V decoupling capacitor (1 F, 0.1 F) con- IN nected closely between Pin 13 (5) and GND Pin 3 (11)? This capacitor carries the MOSFET driver peak currents. 6) For the ...

Page 17

U TYPICAL APPLICATIONS C + IN3 22 F 25V 2 P1A L1 R SENSE3 50 H 0.10 V OUT3 3.3V/1A 0. OUT3 D1 220 F MBRS140T3 10V AVX TPSD226K025R0200 IN3 IN5 C ...

Page 18

LTC1143/LTC1143L LTC1143L-ADJ U TYPICAL APPLICATIONS + C IN1 22 F 0.22 F 25V SENSE1 27 H 0.05 V OUT1 3.3V/2A 1 1000pF C + OUT1 220 F 82.5k MBRS130L 10V 1% 2 ...

Page 19

... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...

Page 20

... Dual Synchronous Controller with Auxiliary Linear Regulator Controller and 5V Standby LTC1539 Dual Synchronous Controller with Phase-Locked Loop TM and Adaptive Power Operation Adaptive Power is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com ...

Related keywords