Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

LTC1702AIGN Datasheet(PDF) 10 Page - Linear Technology

Part # LTC1702AIGN
Description  Dual 550kHz Synchronous 2-Phase Switching Regulator Controller
Download  36 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  LINER [Linear Technology]
Direct Link  http://www.linear.com
Logo LINER - Linear Technology

LTC1702AIGN Datasheet(HTML) 10 Page - Linear Technology

Back Button LTC1702AIGN Datasheet HTML 6Page - Linear Technology LTC1702AIGN Datasheet HTML 7Page - Linear Technology LTC1702AIGN Datasheet HTML 8Page - Linear Technology LTC1702AIGN Datasheet HTML 9Page - Linear Technology LTC1702AIGN Datasheet HTML 10Page - Linear Technology LTC1702AIGN Datasheet HTML 11Page - Linear Technology LTC1702AIGN Datasheet HTML 12Page - Linear Technology LTC1702AIGN Datasheet HTML 13Page - Linear Technology LTC1702AIGN Datasheet HTML 14Page - Linear Technology Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 36 page
background image
10
LTC1702A
1702afa
Figure 2. Floating TG Driver Supply
amp of continuous current with peak currents up to 5A to
slew large MOSFET gates quickly. The external MOSFETs
are connected with the drain of QT attached to the input
supply and the source of QT at the switching node SW. QB
is the synchronous rectifier with its drain at SW and its
source at PGND. SW is connected to one end of the
inductor, with the other end connected to VOUT. The output
capacitor is connected from VOUT to PGND.
When a switching cycle begins, QB is turned off and QT is
turned on. SW rises almost immediately to VIN and the
inductor current begins to increase. When the PWM pulse
finishes, QT turns off and one nonoverlap interval later, QB
turns on. Now SW drops to PGND and the inductor current
decreases. The cycle repeats with the next tick of the
master clock. The percentage of time spent in each mode
is controlled by the duty cycle of the PWM signal, which in
turn is controlled by the feedback amplifier. The master
clock generates a 1VP-P, 550kHz sawtooth waveform and
turns QT once every 1.8
µs. In a typical application with a
5V input and a 1.6V output, the duty cycle will be set at 1.6/
5
× 100% or 32% by the feedback loop. This will give
roughly a 575ns on-time for QT and a 1.22
µs on-time for
QB.
This constant frequency operation brings with it a couple
of benefits. Inductor and capacitor values can be chosen
with a precise operating frequency in mind and the feed-
APPLICATIONS INFORMATION
back loop components can be similarly tightly specified.
Noise generated by the circuit will always be in a known
frequency band with the 550kHz frequency designed to
leave the 455kHz IF band free of interference. Subharmonic
oscillation and slope compensation, common headaches
with constant frequency current mode switchers, are
absent in voltage mode designs like the LTC1702A.
During the time that QT is on, its source (the SW pin) is at
VIN. VIN is also the power supply for the LTC1702A. How-
ever, QT requires VIN + VGS(ON) at its gate to achieve
minimum RON. This presents a problem for the
LTC1702A— it needs to generate a gate drive signal at TG
higher than its highest supply voltage. To get around this,
the TG driver runs from floating supplies, with its negative
supply attached to SW and its power supply at BOOST.
This allows it to slew up and down with the source of QT.
In combination with a simple external charge pump (Fig-
ure 2), this allows the LTC1702A to completely enhance
the gate of QT without requiring an additional, higher
supply voltage.
The two channels of the LTC1702A run from a common
clock, with the phasing chosen to be 180
° from side 1 to
side 2. This has the effect of doubling the frequency of the
switching pulses seen by the input bypass capacitor, sig-
nificantly lowering the RMS current seen by the capacitor
and reducing the value required (see the 2-Phase section).
+
TG
BOOST
SW
BG
PGND
PVCC
DCP
CIN
+
COUT
1702A F02
VOUT
LEXT
VIN
QT
QB
CCP
1
µF
LTC1702A


Similar Part No. - LTC1702AIGN

ManufacturerPart #DatasheetDescription
logo
Linear Technology
LTC1702A LINER-LTC1702A Datasheet
205Kb / 24P
   High Voltage, Current Mode Switching Regulator Controller with Programmable Operating Frequency
LTC1702A LINER-LTC1702A_15 Datasheet
422Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller
More results

Similar Description - LTC1702AIGN

ManufacturerPart #DatasheetDescription
logo
Linear Technology
LTC1702 LINER-LTC1702_15 Datasheet
421Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller
LTC1702 LINER-LTC1702 Datasheet
350Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller
LTC1702A LINER-LTC1702A_15 Datasheet
422Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller
LTC3728L-1 LINER-LTC3728L-1 Datasheet
480Kb / 32P
   Dual, 550kHz, 2-Phase Synchronous Regulator
LTC3728L-1 LINER-LTC3728L-1_15 Datasheet
480Kb / 32P
   Dual, 550kHz, 2-Phase Synchronous Regulator
LTC3728 LINER-LTC3728_15 Datasheet
1Mb / 36P
   Dual, 550kHz, 2-Phase Synchronous Step-Down Switching Regulator
LTC3728 LINER-LTC3728 Datasheet
676Kb / 32P
   Dual, 550kHz, 2-Phase Synchronous Step-Down Switching Regulator
LTC1703 LINER-LTC1703_15 Datasheet
390Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller with 5-Bit VID
LTC1703 LINER-LTC1703 Datasheet
343Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller with 5-Bit VID
LTC1703IG LINER-LTC1703IG Datasheet
345Kb / 36P
   Dual 550kHz Synchronous 2-Phase Switching Regulator Controller with 5-Bit VID
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.NET
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com