Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

RT8295B Datasheet(PDF) 11 Page - Richtek Technology Corporation

Part # RT8295B
Description  2A, 23V, 1.2MHz Synchronous Step-Down Converter
Download  14 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  RICHTEK [Richtek Technology Corporation]
Direct Link  http://www.richtek.com
Logo RICHTEK - Richtek Technology Corporation

RT8295B Datasheet(HTML) 11 Page - Richtek Technology Corporation

Back Button RT8295B Datasheet HTML 6Page - Richtek Technology Corporation RT8295B Datasheet HTML 7Page - Richtek Technology Corporation RT8295B Datasheet HTML 8Page - Richtek Technology Corporation RT8295B Datasheet HTML 9Page - Richtek Technology Corporation RT8295B Datasheet HTML 10Page - Richtek Technology Corporation RT8295B Datasheet HTML 11Page - Richtek Technology Corporation RT8295B Datasheet HTML 12Page - Richtek Technology Corporation RT8295B Datasheet HTML 13Page - Richtek Technology Corporation RT8295B Datasheet HTML 14Page - Richtek Technology Corporation  
Zoom Inzoom in Zoom Outzoom out
 11 / 14 page
background image
RT8295B
11
DS8295B-03
March 2011
www.richtek.com
OUTL
OUT
1
V
I
ESR
8fC

≤ ∆+


The output ripple will be highest at the maximum input
voltage since
∆IL increases with input voltage. Multiple
capacitors placed in parallel may be needed to meet the
ESR and RMS current handling requirement. Dry tantalum,
special polymer, aluminum electrolytic and ceramic
capacitors ar e all av ai labl e in surf ace m ount
packages.Special polymer capacitors offer very low ESR
value. However, it provides lower capacitance density than
other types. Although Tantalum capacitors have the highest
capacitance density, it is important to only use types that
pass the surge test for use in switching power supplies.
Aluminum electrolytic capacitors have significantly higher
ESR. However, it can be used in cost-sensitive applications
for ripple current rating and long term reliability
considerations. Ceramic capacitors have excellent low
ESR characteristics but can have a high voltage coefficient
and audible piezoelectric effects. The high Q of ceramic
capacitors with trace inductance can also lead to significant
ringing.
Higher values, lower cost ceramic capacitors are now
becoming available in smaller case sizes. Their high ripple
current, high voltage rating and low ESR make them ideal
for switching regulator applications. However, care must
be taken when these capacitors are used at input and
output. When a ceramic capacitor is used at the input
and the power is supplied by a wall adapter through long
wires, a load step at the output can induce ringing at the
response as described in a later section.
The output ripple,
∆VOUT , is determined by :
input, VIN. At best, this ringing can couple to the output
and be mistaken as loop instability. At worst, a sudden
inrush of current through the long wires can potentially
cause a voltage spike at VIN large enough to damage the
part.
Checking Transient Response
The regulator loop response can be checked by looking
at the load transient response. Switching regulators take
several cycles to respond to a step in load current. When
a load step occurs, VOUT immediately shifts by an amount
equal to
∆ILOAD (ESR) and COUT also begins to be charged
or discharged to generate a feedback error signal for the
regulator to return VOUT to its steady-state value. During
this recovery time, VOUT can be monitored for overshoot or
ringing that would indicate a stability problem.
EMI Consideration
Since parasitic inductance and capacitance effects in PCB
circuitry would cause a spike voltage on SW pin when
high side MOSFET is turned-on/off, this spike voltage on
SW may impact on EMI performance in the system. In
order to enhance EMI performance, there are two methods
to suppress the spike voltage. One way is by placing an
R-C snubber between SW and GND and locating them as
close as possible to the SW pin (see Figure 5). Another
method is by adding a resistor in series with the bootstrap
capacitor, CBOOT, but this method will decrease the driving
capability to the high side MOSFET. It is strongly
recommended to reserve the R-C snubber during PCB
layout for EMI improvement. Moreover, reducing the SW
trace area and keeping the main power in a small loop will
be helpful on EMI performance. For detailed PCB layout
guide, please refer to the section Layout Considerations.
Figure 5. Reference Circuit with Snubber and Enable Timing Control
VIN
EN
GND
BOOT
FB
SW
7
5
2
3
1
L
3.6
µH
100nF
22
µFx2
R1
75k
R2
24k
VOUT
3.3V/2A
10
µF
Chip Enable
VIN
4.5V to 23V
RT8295B
SS
8
CSS
0.1
µF
COMP
CC
0.82nF
RC
32k
CP
NC
6
4,
9 (Exposed Pad)
CBOOT
COUT
CIN
RBOOT*
RS*
CS*
REN*
CEN*
* : Optional


Similar Part No. - RT8295B

ManufacturerPart #DatasheetDescription
logo
Richtek Technology Corp...
RT8295A RICHTEK-RT8295A Datasheet
296Kb / 14P
   2A, 23V, 340kHz Synchronous Step-Down Converter
RT8295AHZSP RICHTEK-RT8295AHZSP Datasheet
584Kb / 11P
   Evaluation Board
More results

Similar Description - RT8295B

ManufacturerPart #DatasheetDescription
logo
Richtek Technology Corp...
RT8252B RICHTEK-RT8252B Datasheet
199Kb / 14P
   2A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8282B RICHTEK-RT8282B Datasheet
204Kb / 14P
   2A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8292B RICHTEK-RT8292B Datasheet
298Kb / 14P
   2A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8253B RICHTEK-RT8253B Datasheet
205Kb / 15P
   3A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8283B RICHTEK-RT8283B Datasheet
205Kb / 14P
   3A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8296B RICHTEK-RT8296B Datasheet
290Kb / 15P
   3A, 23V, 1.2MHz Synchronous Step-Down Converter
RT8293B RICHTEK-RT8293B Datasheet
289Kb / 14P
   3A, 23V, 1.2MHz Synchronous Step-Down Converter
logo
Analog Intergrations Co...
AIC2857F AIC-AIC2857F Datasheet
514Kb / 12P
   2A 23V Synchronous Step-Down Converter
logo
Unisonic Technologies
UD05201 UTC-UD05201 Datasheet
366Kb / 5P
   1.2MHZ, 2A SYNCHRONOUS STEP-DOWN CONVERTER
logo
Richtek Technology Corp...
RT2652 RICHTEK-RT2652 Datasheet
205Kb / 12P
   2A, 1.2MHz Synchronous Step-Down Converter
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14


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
Family Site : ic2ic.com  |   icmetro.com