Zakładka z wyszukiwarką danych komponentów
  Polish  ▼
ALLDATASHEET.PL

X  

BD35281HFN Arkusz danych(PDF) 6 Page - Rohm

Numer części BD35281HFN
Szczegółowy opis  Nch FET Ultra LDO for Desktop PCs
Download  16 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Producent  ROHM [Rohm]
Strona internetowa  http://www.rohm.com
Logo ROHM - Rohm

BD35281HFN Arkusz danych(HTML) 6 Page - Rohm

Back Button BD35281HFN Datasheet HTML 2Page - Rohm BD35281HFN Datasheet HTML 3Page - Rohm BD35281HFN Datasheet HTML 4Page - Rohm BD35281HFN Datasheet HTML 5Page - Rohm BD35281HFN Datasheet HTML 6Page - Rohm BD35281HFN Datasheet HTML 7Page - Rohm BD35281HFN Datasheet HTML 8Page - Rohm BD35281HFN Datasheet HTML 9Page - Rohm BD35281HFN Datasheet HTML 10Page - Rohm Next Button
Zoom Inzoom in Zoom Outzoom out
 6 / 16 page
background image
Technical Note
6/15
www.rohm.com
2011.01 - Rev.A
© 2011 ROHM Co., Ltd. All rights reserved.
BD35281HFN
Operation of Each Block
AMP
This is an error amp that compares the reference voltage (0.65V) with VO to drive the output Nch FET (Ron=150mΩ).
Frequency optimization helps to realize rapid transient response, and to support the use of ceramic capacitors on the
output capacitors. AMP input voltage ranges from GND to 2.7V, while the AMP output ranges from GND to VCC. When EN
is OFF, or when UVLO is active, output goes LOW and the output of the NchFET switches OFF.
EN
The EN block controls the regulator’s ON/OFF state via the EN logic input pin. In the OFF position, circuit voltage is
maintained at 0µA, thus minimizing current consumption at standby. The FET is switched ON to enable discharge of the
NRCS pin VO, thereby draining the excess charge and preventing the IC on the load side from malfunctioning. Since no
electrical connection is required (e.g. between the VCC pin and the ESD prevention diode), module operation is
independent of the input sequence.
VCCUVLO
To prevent malfunctions that can occur during a momentary decrease in VCC, the UVLO circuit switches the output OFF,
and (like the EN block) discharges NRCS and VO. Once the UVLO threshold voltage (TYP3.80V) is reached, the power-on
reset is triggered and output continues.
VINUVLO
When VD voltage exceeds the threshold voltage, VDUVLO becomes active. Once active, the status of output voltage
remains ON even if VD voltage drops. (When VIN voltage drops, SCP engages and output switches OFF.)
Unlike EN and VCC, it is effective at output startup. VDUVLO can be restored either by reconnecting the EN pin or VCC pin.
CURRENT LIMIT
When output is ON, the current limit function monitors the internal IC output current against the parameter value. When
current exceeds this level, the current limit module lowers the output current to protect the load IC. When the overcurrent
state is eliminated, output voltage is restored to the parameter value. However, when output voltage falls to or below the
SCP startup voltage, the SCP function becomes active and the output switches OFF.
NRCS (Non Rush Current on Start-up)
The soft start function enabled by connecting an external capacitor between the NRCS pin and ground. Output ramp-up
can be set for any period up to the time the NRCS pin reaches VFB (0.65V). During startup, the NRCS pin serves as a
20µA (TYP) constant current source to charge the external capacitor. Output start time is calculated via the formula below.
NRCS
FB
NRCS
NRCS
I
V
C
.)
typ
(
T
TSD (Thermal Shut down)
The shutdown (TSD) circuit automatically is latched OFF when the chip temperature exceeds the threshold temperature
after the programmed time period elapses, thus serving to protect the IC against “thermal runaway” and heat damage.
Because the TSD circuit is intended to shut down the IC only in the presence of extreme heat, it is crucial that the Tj (max)
parameter not be exceeded in the thermal design ,in order to avoid potential problems with the TSD.
VIN
The VIN line acts as the major current supply line, and is connected to the output NchFET drain. Since no electrical
connection (such as between the VCC pin and the ESD protection diode) is necessary, VIN operates independent of the
input sequence. However, since an output NchFET body diode exists between VIN and VO, a VIN-VO electric (diode)
connection is present. Note, therefore, that when output is switched ON or OFF, reverse current may flow to VIN from VO.
SCP
When output voltage (Vo) drops, the IC assumes that VO pin is shorted to GND and switches the output voltage OFF. After
the GND short has been detected and the programmed delay time has elapsed, output is latched OFF. It is also effective
during output startup. SCP can be cleared either by reconnecting the EN pin or VCC pin.


Podobny numer części - BD35281HFN

ProducentNumer częściArkusz danychSzczegółowy opis
logo
Rohm
BD35281HFN ROHM-BD35281HFN Datasheet
137Kb / 5P
   Silicon Monolithic Integrated Circuit
More results

Podobny opis - BD35281HFN

ProducentNumer częściArkusz danychSzczegółowy opis
logo
Rohm
BD3523HFN ROHM-BD3523HFN_09 Datasheet
788Kb / 21P
   Nch FET Ultra LDOs for Desktop PCs
BD3540NUV ROHM-BD3540NUV_09 Datasheet
642Kb / 17P
   Nch FET Ultra LDOs for Desktop PCs Chipsets with Power Good
BD3506F ROHM-BD3506F_10 Datasheet
534Kb / 15P
   Nch FET Ultra LDO for PC Chipsets
BD3507HFV ROHM-BD3507HFV_10 Datasheet
479Kb / 16P
   Nch FET Ultra LDO for PC Chipsets
BD3509MUV ROHM-BD3509MUV_10 Datasheet
665Kb / 21P
   Nch FET Ultra LDO for PC Chipsets
BD3504FVM ROHM-BD3504FVM_10 Datasheet
549Kb / 17P
   Nch FET Ultra LDO Controllers for PC Chipsets
logo
Analog Devices
ADM9264 AD-ADM9264 Datasheet
181Kb / 12P
   Quad Power Supply Monitor for Desktop PCs
REV. 0
ADM9264 AD-ADM9264_15 Datasheet
189Kb / 12P
   Quad Power Supply Monitor for Desktop PCs
REV. 0
logo
PhaseLink Corporation
PLL103-02 PLL-PLL103-02 Datasheet
178Kb / 6P
   DDR SDRAM Buffer for Desktop PCs with 4 DDR DIMMS
logo
List of Unclassifed Man...
PLL103-02 ETC1-PLL103-02 Datasheet
208Kb / 7P
   DDR SDRAM Buffer for Desktop PCs with 4 DDR DIMMS
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16


Arkusz danych Pobierz

Go To PDF Page


Link URL




Polityka prywatności
ALLDATASHEET.PL
Czy Alldatasheet okazała się pomocna?  [ DONATE ] 

O Alldatasheet   |   Reklama   |   Kontakt   |   Polityka prywatności   |   Linki   |   Lista producentów
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