Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

NCP81243 Datasheet(PDF) 19 Page - ON Semiconductor

Part No. NCP81243
Description  Dual Output 3 & 2 Phase Controller
Download  26 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  ONSEMI [ON Semiconductor]
Direct Link  http://www.onsemi.com
Logo ONSEMI - ON Semiconductor

NCP81243 Datasheet(HTML) 19 Page - ON Semiconductor

Back Button NCP81243_17 Datasheet HTML 15Page - ON Semiconductor NCP81243_17 Datasheet HTML 16Page - ON Semiconductor NCP81243_17 Datasheet HTML 17Page - ON Semiconductor NCP81243_17 Datasheet HTML 18Page - ON Semiconductor NCP81243_17 Datasheet HTML 19Page - ON Semiconductor NCP81243_17 Datasheet HTML 20Page - ON Semiconductor NCP81243_17 Datasheet HTML 21Page - ON Semiconductor NCP81243_17 Datasheet HTML 22Page - ON Semiconductor NCP81243_17 Datasheet HTML 23Page - ON Semiconductor Next Button
Zoom Inzoom in Zoom Outzoom out
 19 / 26 page
background image
NCP81243
www.onsemi.com
19
Remote Sense Amplifier
A high performance high input impedance true
differential amplifier is provided to accurately sense the
output voltage of the regulator. The VSP and VSN inputs
should be connected to the regulator’s output voltage sense
points. The remote sense amplifier takes the difference of
the output voltage with the DAC voltage and adds the droop
voltage to VDIFOUT =
V
VSP * VVSN ) 1.3 V * VDAC ) VDROOP * VCSREF
This signal then goes through a standard error
compensation network and into the inverting input of the
error amplifier. The non−inverting input of the error
amplifier is connected to the same 1.3 V reference used for
the differential sense amplifier output bias.
High Performance Voltage Error Amplifier
A high performance error amplifier is provided for high
bandwidth transient performance. A standard type III
compensation circuit is normally used to compensate the
system.
Differential Current Feedback Amplifiers
Each phase has a low offset differential amplifier to sense
that phase current for current balance. The inputs to the
CSNx and CSPx pins are high impedance inputs. It is
recommended that any external filter resistor RCSN does
not exceed 10 k
W to avoid offset issues with leakage current.
It is also recommended that the voltage sense element be no
less than 0.5 k
W for accurate current balance. Fine tuning of
this time constant is generally not required. The individual
phase current is summed into the PWM comparator
feedback this way current is balanced via a current mode
control approach.
CCSN
RCSN
DCR
LPHASE
1
2
SWNx
VOUT
R
CSN +
L
PHASE
C
CSN @ DCR
Total Current Sense Amplifier
The NCP81243 uses a patented approach to sum the phase
currents into a single temperature compensated total current
signal. This signal is then used to generate the output voltage
droop, total current limit, and the output current monitoring
functions. The total current signal is floating with respect to
CSREF. The current signal is the difference between
CSCOMP and CSREF. The Ref(n) resistors sum the signals
from the output side of the inductors to create a low
impedance virtual ground. The amplifier actively filters and
gains up the voltage applied across the inductors to recover
the voltage drop across the inductor series resistance (DCR).
Rth is placed near an inductor to sense the temperature of the
inductor. This allows the filter time constant and gain to be
a function of the Rth NTC resistor and compensate for the
change in the DCR with temperature.
The DC gain equation for the current sensing:
V
CSCOMP−CSREF +
*
Rcs2
) Rcs1@Rth
Rcs1
)Rth
Rph
@ Iout
Total @ DCR
Set the gain by adjusting the value of the Rph resistors.
The DC gain should be set to the output voltage droop. If the
voltage from CSCOMP to CSREF is less than 100 mV at
ICCMAX then it is recommend increasing the gain of the
CSCOMP amp. This is required to provide a good current
signal to offset voltage ratio for the ILIMIT pin. When no
droop is needed, the gain of the amplifier should be set to
provide ~100 mV across the current limit programming
resistor at full load. The values of Rcs1 and Rcs2 are set
based on the 220k NTC and the temperature effect of the
inductor and should not need to be changed. The NTC
should be placed near the closest inductor. The output
voltage droop should be set with the droop filter divider.
The pole frequency in the CSCOMP filter should be set
equal to the zero from the output inductor. This allows the
circuit to recover the inductor DCR voltage drop current
signal. Ccs1 and Ccs2 are in parallel to allow for fine tuning
of the time constant using commonly available values. It is
best to fine tune this filter during transient testing.


Similar Part No. - NCP81243_17

ManufacturerPart No.DatasheetDescription
ON Semiconductor
ON Semiconductor
NCP81243MNTXG ONSEMI-NCP81243MNTXG Datasheet
338Kb / 26P
   Dual Output 3 & 2 Phase Controller
February, 2016 ??Rev. 0
More results

Similar Description - NCP81243_17

ManufacturerPart No.DatasheetDescription
ON Semiconductor
ON Semiconductor
NCP81243 ONSEMI-NCP81243 Datasheet
338Kb / 26P
   Dual Output 3 & 2 Phase Controller
February, 2016 ??Rev. 0
NCP6121 ONSEMI-NCP6121 Datasheet
315Kb / 28P
   Dual Output 3 Phase 1/0 Phase Controller
January, 2013 ??Rev. 2
Linear Technology
Linear Technology
LTC3788-1 LINER-LTC3788-1_15 Datasheet
387Kb / 30P
   2-Phase, Dual Output Synchronous Boost Controller
LTC3788 LINER-LTC3788 Datasheet
427Kb / 32P
   2-Phase, Dual Output Synchronous Boost Controller
LTC3788 LINER-LTC3788_15 Datasheet
411Kb / 32P
   2-Phase, Dual Output Synchronous Boost Controller
LTC3788 LINER-LTC3788_1 Datasheet
372Kb / 32P
   2-Phase, Dual Output Synchronous Boost Controller
LTC3788-1 LINER-LTC3788-1 Datasheet
415Kb / 28P
   2-Phase, Dual Output Synchronous Boost Controller
LTC3788-1 LINER-LTC3788-1_1 Datasheet
366Kb / 30P
   2-Phase, Dual Output Synchronous Boost Controller
ON Semiconductor
ON Semiconductor
NCP6153 ONSEMI-NCP6153 Datasheet
394Kb / 29P
   Dual Output 3/4 Phase 1/0 Phase Controller
October, 2012 ??Rev. 1
International Rectifier
International Rectifier
IR35204 IRF-IR35204 Datasheet
1Mb / 61P
   31 Dual Output Digital Multi-Phase Controller
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 


Datasheet Download

Go To PDF Page


Link URL




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

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   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