LTC3830 LINER [Linear Technology], LTC3830 Datasheet

no-image

LTC3830

Manufacturer Part Number
LTC3830
Description
High Power Step-Down Synchronous DC/DC Controllers for Low Voltage Operation
Manufacturer
LINER [Linear Technology]
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
LTC3830-1ES8
Manufacturer:
LT
Quantity:
10 000
Part Number:
LTC3830-1ES8#PBF
Manufacturer:
TI
Quantity:
1 200
Part Number:
LTC3830-1ES8#TRPBF
Manufacturer:
LT
Quantity:
4 420
Part Number:
LTC3830EGN
Manufacturer:
LT
Quantity:
10 000
Part Number:
LTC3830EGN
Manufacturer:
LINEAR
Quantity:
20 000
Part Number:
LTC3830EGN-8
Manufacturer:
LT
Quantity:
10 000
Company:
Part Number:
LTC3830ES
Quantity:
240
Part Number:
LTC3830ES#PBF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
Part Number:
LTC3830ES8
Manufacturer:
LINEAR/凌特
Quantity:
20 000
FEATURES
TYPICAL APPLICATIO
APPLICATIO S
CPU Power Supplies
Multiple Logic Supply Generator
Distributed Power Applications
High Efficiency Power Conversion
High Power Switching Regulator Controller
for 3.3V-5V to 1.xV-3.xV Step-Down Applications
No Current Sense Resistor Required
Low Input Supply Voltage Range: 3V to 8V
Maximum Duty Cycle > 91% Over Temperature
All N-Channel External MOSFETs
Excellent Output Regulation: 1% Over Line, Load
and Temperature Variations
High Efficiency: Over 95% Possible
Adjustable or Fixed 3.3V Output (16-Pin Version)
Programmable Fixed Frequency Operation: 100kHz to
500kHz
External Clock Synchronization
Soft-Start (Some Versions)
Low Shutdown Current: <10 A
Overtemperature Protection
Available in S8, S16 and SSOP-16 Packages
12.7k 1%
0.1 F
15k
Figure 1. High Efficiency 3V-8V to 1.8V Power Converter
0.01 F
5.36k 1%
3.3nF
SS
COMP
GND
FB
LTC3830-1
U
PV
PV
4.7 F
CC2
CC1
G1
G2
L: SUMIDA CDEP105-3R2MC-88
C
OUT
: PANASONIC EEFUEOD271R
12V
5.1
3V TO 8V
4.7 F
V
U
IN
M1
Si7806DN
M2
Si7806DN
+
220 F
10V
B320A
3.2 H
L
+
3830 F01
Synchronous DC/DC Controllers
C
270 F
2V
OUT
DESCRIPTIO
The LTC
ciency switching regulator controllers optimized for
3.3V-5V to 1.xV-3.xV step-down applications. A preci-
sion internal reference and feedback system provide
and line voltage variations. The LTC3830/LTC3830-1 use
a synchronous switching architecture with N-channel
MOSFETs. Additionally, the chip senses output current
through the drain-source resistance of the upper
N-channel FET, providing an adjustable current limit
without a current sense resistor.
The LTC3830/LTC3830-1 operate with an input supply
voltage as low as 3V and with a maximum duty cycle of
>91% over temperature. They include a fixed frequency
PWM oscillator for low output ripple operation. The 200kHz
free-running clock frequency can be externally adjusted or
synchronized with an external signal from 100kHz to 500kHz.
In shutdown mode, the LTC3830 supply current drops to
<10 A. The LTC3830-1 differs from the LTC3830 S8 ver-
sion by replacing shutdown with a soft-start function.
For a similar, pin compatible DC/DC converter with an
output voltage as low as 0.6V, please refer to the LTC3832.
1.8V
9A
1% output regulation over temperature, load current
, LTC and LT are registered trademarks of Linear Technology Corporation.
for Low Voltage Operation
®
3830/LTC3830-1 are high power, high effi-
High Power Step-Down
100
90
80
70
60
50
40
U
LTC3830/LTC3830-1
0
1
2
3
LOAD CURRENT (A)
Efficiency
4
5
6
7
V
V
IN
OUT
8
= 3.3V
= 1.8V
3830 TA02
9
10
sn3830 3830fs
1

Related parts for LTC3830

LTC3830 Summary of contents

Page 1

... In shutdown mode, the LTC3830 supply current drops to <10 A. The LTC3830-1 differs from the LTC3830 S8 ver- sion by replacing shutdown with a soft-start function. For a similar, pin compatible DC/DC converter with an output voltage as low as 0.6V, please refer to the LTC3832. ...

Page 2

... A CC CC1 CC2 CONDITIONS (Note 1.25V COMP V = 1.25V COMP 10A (Note 6) OUT V = 4.75V to 5.25V CC ORDER PART NUMBER TOP VIEW LTC3830EGN LTC3830ES CC2 PART MARKING MAX 6 11 ...

Page 3

... Note 3: Supply current in normal operation is dominated by the current needed to charge and discharge the external FET gates. This will vary with the LTC3830 operating frequency, operating voltage and the external FETs used. Note 4: The open-loop DC gain and transconductance from the SENSE – ...

Page 4

... LTC3830/LTC3830 TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 3. REFER TO FIGURE 12 3.33 3.32 3.31 3.30 3.29 3.28 3.27 3.26 –10 – –15 0 OUTPUT CURRENT (A) 3830 G02 Output Voltage Temperature Drift 3.34 REFER TO FIGURE 12 OUTPUT = NO LOAD 3.33 3.32 3.31 3.30 3.29 3.28 3.27 3.26 –50 – 100 125 TEMPERATURE ( C) 3830 G04 Oscillator Frequency vs Temperature 250 ...

Page 5

... G15 V Operating Supply Current CC vs Temperature 1.6 FREQSET FLOATING 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 –50 – 100 125 TEMPERATURE ( C) 3830 G18 LTC3830/LTC3830-1 Output Overcurrent Protection 3 3.0 REFER TO FIGURE 20k IMAX 2.5 2.0 1.5 1.0 0 OUTPUT CURRENT (A) 3830 G13 Soft-Start Sink Current vs (V – V ...

Page 6

... CC1 and the 8-lead LTC3830. SHDN (Pin 8/Pin 5/NA): Shutdown. A TTL compatible low + V . level at SHDN for longer than 100 s puts the LTC3830 into IN GS(ON)(Q1) shutdown mode. In shutdown, G1 and G2 go low, all internal circuits are disabled and the quiescent current drops max. A TTL compatible high level at SHDN allows the part to operate normally ...

Page 7

... Power Supply Input. All low CC power internal circuits draw their supply from this pin. Connect this pin to a clean power supply, separate from the main V 4.7 F bypass capacitor. The LTC3830-1 and the 8-lead LTC3830 have V MAX require bypass capacitor to GND. PV (Pin 15/Pin 7/Pin 7): Power Supply Input for G2 ...

Page 8

... N-channel power MOSFET as a current sensing element, eliminating the need for an external sense resistor. Also included in the 16-lead version and the LTC3830 internal soft-start feature that requires only a single external capacitor to operate. In addition, 16-lead parts ...

Page 9

... The 16-lead LTC3830 devices include a soft-start circuit that is used for start-up and current limit operation. The LTC3830-1 only has the soft-start function; the current limit function is disabled. The 8-lead LTC3830 has both the soft-start and current limit function disabled. The SS pin requires an external capacitor, C ...

Page 10

... CC1 LTC3830-1 does not have this shutdown function. External Clock Synchronization V IN The LTC3830 SHDN pin doubles as an external clock input + for applications that require a synchronized clock internal circuit forces the LTC3830 into external synchro- nization mode if a negative transition at the SHDN pin is detected ...

Page 11

... The low period of this clock signal must not be >100 s, or else the LTC3830 enters shutdown mode. Figure 5 describes the operation of the external synchro- nization function. A negative transition at the SHDN pin forces the internal ramp signal low to restart a new PWM cycle ...

Page 12

... APPLICATIO S I FOR ATIO filter capacitors. 100 and 4.7 F usually provide ad- equate filtering for V . For best performance, connect the CC 4.7 F bypass capacitor as close to the LTC3830 V possible. Gate drive for the top N-channel MOSFET Q1 is supplied from PV . This supply must be above V CC1 power supply input least one power MOSFET V for efficient operation ...

Page 13

... DS(ON) allowable power dissipation and maximum output current typical LTC3830 circuit, operating in continuous mode, the average inductor current is equal to the output load current. This current flows through either with the power dissipation split up according to the duty cycle: ...

Page 14

... The maximum rate of rise of inductor current is set by the inductor’s value, the input-to-output voltage differential and the LTC3830’s maximum duty cycle typical 5V input, 3.3V output application, the maximum rise time will be: DC ...

Page 15

... This action causes a temporary voltage droop at the output. To minimize this effect, the inductor value should usually be in the range for most 5V input LTC3830 circuits. To optimize performance, different combinations of input and output voltages and expected loads may require different inductor values ...

Page 16

... ESR of 0.04 ; three in parallel lower the net output capacitor ESR to 0.013 . Feedback Loop Compensation The LTC3830 voltage feedback loop is compensated at the COMP pin, which is the output node of the error amplifier. The feedback loop is generally compensated with network from COMP to GND as shown in Figure 10a. ...

Page 17

... LC ESR f CO Figure 10b. Bode Plot of the LTC3830 Overall Transfer Function W U Although a mathematical approach to frequency compen- sation can be used, the added complication of input and/or output filters, unknown capacitor ESR, and gross operat- ing point changes with input voltage, load current varia- tions, all suggest a more practical empirical method ...

Page 18

... The GND and PGND pins should be shorted directly at the LTC3830. This helps to minimize internal ground dis- turbances in the LTC3830 and prevent differences in ground potential from disrupting internal circuit operation. This C (nF) ...

Page 19

... Do not connect these parts to the ground plane! 4. The and PV decoupling capacitors should CC CC1 CC2 be as close to the LTC3830 as possible. The 4.7 F and 1 F bypass capacitors shown CC1 provide optimum regulation performance ...

Page 20

... SHUTDOWN 33pF 18k C 0. MBR0530T1 + 6. CC2 CC1 0 0 MAX 1k LTC3830 I FB FREQSET G2 SHDN PGND COMP GND + SENSE C : SANYO 6TPB330M – SENSE C : SANYO 4TPB470M OUT L : SUMIDA CDEP105-2R5 O Q1, Q2: VISHAY Si7892DP Figure 12 3.3V, 10A Application + C IN ...

Page 21

... TYP .015 .004 45 .053 – .068 (0.38 0.10) (1.351 – 1.727) 0 – 8 TYP .008 – .012 (0.203 – 0.305) LTC3830/LTC3830-1 .189 – .196* (4.801 – 4.978) .009 (0.229 REF .150 – .157** (3.810 – 3.988) ...

Page 22

... LTC3830/LTC3830-1 PACKAGE DESCRIPTIO .050 BSC N .245 MIN 1 2 .030 .005 TYP RECOMMENDED SOLDER PAD LAYOUT .010 – .020 (0.254 – 0.508) .008 – .010 (0.203 – 0.254) NOTE: 1. DIMENSIONS IN 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) ...

Page 23

... N .053 – .069 (1.346 – 1.752) 0 – 8 TYP .014 – .019 (0.355 – 0.483) TYP LTC3830/LTC3830-1 .386 – .394 (9.804 – 10.008) NOTE .150 – .157 (3.810 – 3.988) ...

Page 24

... L : SUMIDA CDEP105-1R3 O NC Q1, Q2: VISHAY Si7892DP COMMENTS LTC3830 is Pin-for-Pin Compatible and is Recommended for New Designs SO-8 with Current Limit Constant Frequency, Standby 5V and 3.3V LDOs, 3.5V V 550kHz, 25MHz GBW Voltage Mode, V Provides CPU Core, I/O and CLK Supplies for Portable Systems Current Mode, V Fault Protection, Power Good, 3 ...

Related keywords