Motore di ricerca datesheet componenti elettronici
  Italian  ▼
ALLDATASHEETIT.COM

X  

L6995S Scheda tecnica(PDF) 11 Page - STMicroelectronics

Il numero della parte L6995S
Spiegazioni elettronici  LOSSLESS CURRENT LIMIT
Download  26 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Produttore elettronici  STMICROELECTRONICS [STMicroelectronics]
Homepage  http://www.st.com
Logo STMICROELECTRONICS - STMicroelectronics

L6995S Scheda tecnica(HTML) 11 Page - STMicroelectronics

Back Button L6995S Datasheet HTML 7Page - STMicroelectronics L6995S Datasheet HTML 8Page - STMicroelectronics L6995S Datasheet HTML 9Page - STMicroelectronics L6995S Datasheet HTML 10Page - STMicroelectronics L6995S Datasheet HTML 11Page - STMicroelectronics L6995S Datasheet HTML 12Page - STMicroelectronics L6995S Datasheet HTML 13Page - STMicroelectronics L6995S Datasheet HTML 14Page - STMicroelectronics L6995S Datasheet HTML 15Page - STMicroelectronics Next Button
Zoom Inzoom in Zoom Outzoom out
 11 / 26 page
background image
Obsolete
Product(s)
- Obsolete
Product(s)
11/26
L6995S
4.6 Protection and fault
Sensing VSENSE pin voltage performs output protection. The nature of the fault (that is, latched OV or latched
UV) is given by the PGOOD and OVP pins. If the output voltage is between the 89% (typ.) and 110% (typ) of
the regulated value, PGOOD is high. If a hard overvoltage or an undervoltage occurs, the device is latched: low
side MOSFET is turned on, high side MOSFET is turned off and PGOOD goes low. In case the system detects
an overvoltage the OVP pin goes high.
To recover the functionality the device must be shut down and restarted thought the SHDN pin, or the supply
has to be removed, and restart with the correct sequence.
These features are useful to protect against short-circuit (UV fault) as well as high side MOSFET short (OV
fault).
4.7 Drivers
The integrated high-current drivers allow using different size of power MOSFET, maintaining fast switching tran-
sition. The driver for the high side MOSFET uses the BOOT pin for supply and PHASE pin for return (floating
driver). The driver for the low side MOSFET uses the VDR pin for the supply and PGND pin for the return. The
main feature is the adaptive anti-cross-conduction protection, which prevents from both high side and low side
MOSFET to be on at the same time, avoiding a high current to flow from VIN to GND. When high side MOSFET
is turned off the voltage on the pin PHASE begins to fall; the low side MOSFET is turned on only when the volt-
age on PHASE pin reaches 250mV. When low side is turned off, high side remains off until LGATE pin voltage
reaches 500mV. This is important since the driver can work properly with a large range of external power MOS-
FETS.
The current necessary to switch the external MOSFETS flows through the device, and it is proportional to the
MOSFET gate charge and the switching frequency. So the power dissipation of the device is function of the ex-
ternal power MOSFET gate charge and switching frequency.
Eq 14
The maximum gate charge values for the low side and high side are given from:
Eq 15
Eq 16
Where fSW0 = 500Khz. The equations above are valid for TJ = 150°C. If the system temperature is lower the QG
can be higher.
For the Low Side driver the max output gate charge meets another limit due to the internal traces degradation;
in this case the maximum value is QMAXLS = 125nC.
The low side driver has been designed to have a low resistance pull-down transistor, around 0.5 ohms. This
prevents the voltage on LGATE pin raises during the fast rise-time of the pin PHASE, due to the Miller effect.
5
APPLICATION INFORMATION
5.1 20A Demo board description
The demoboard shows the device operation in general purpose applications. The evaluation board allows using
only one supply because the on board linear regulator LM317LD; the linear regulator supplies the device
through the J1. Output current in excess of 20A can be reached dependently on the MOSFET type. The SW1
is used to start the device (when the supplies are already present) and to select the PFM/PWM mode.
P
driver
V
cc
Q
gTOT
F
SW
⋅⋅
=
Q
MAXHS
f
SW0
f
SW
------------- 75nC
=
Q
MAXLS
f
SW0
f
SW
------------- 125nC
=


Codice articolo simile - L6995S

Produttore elettroniciIl numero della parteScheda tecnicaSpiegazioni elettronici
logo
STMicroelectronics
L6995 STMICROELECTRONICS-L6995 Datasheet
336Kb / 25P
   STEP DOWN CONTROLLER FOR HIGH DIFFERENTIAL INPUT-OUTPUT CONVERSION
L6995D STMICROELECTRONICS-L6995D Datasheet
336Kb / 25P
   STEP DOWN CONTROLLER FOR HIGH DIFFERENTIAL INPUT-OUTPUT CONVERSION
L6995DTR STMICROELECTRONICS-L6995DTR Datasheet
336Kb / 25P
   STEP DOWN CONTROLLER FOR HIGH DIFFERENTIAL INPUT-OUTPUT CONVERSION
More results

Descrizione simile - L6995S

Produttore elettroniciIl numero della parteScheda tecnicaSpiegazioni elettronici
logo
Maxim Integrated Produc...
MAX8537EVKIT MAXIM-MAX8537EVKIT Datasheet
228Kb / 11P
   Lossless Adjustable Hiccup Current Limit
Rev 0; 7/04
logo
Richtek Technology Corp...
RT2530Q RICHTEK-RT2530Q Datasheet
141Kb / 10P
   Current Limit
logo
Advanced Monolithic Sys...
AMS3131 ADMOS-AMS3131 Datasheet
319Kb / 9P
   Current Limit protection
AMS3132 ADMOS-AMS3132 Datasheet
439Kb / 10P
   Current Limit protection
logo
STMicroelectronics
STEVAL-ISA052V2 STMICROELECTRONICS-STEVAL-ISA052V2 Datasheet
137Kb / 4P
   Negative current limit
May 2008 Rev 1
logo
M.S. Kennedy Corporatio...
MSK146 MSK-MSK146_15 Datasheet
246Kb / 8P
   Programmable Current Limit
logo
STMicroelectronics
STEVAL-ISA052V1 STMICROELECTRONICS-STEVAL-ISA052V1 Datasheet
123Kb / 4P
   Negative current limit
November 2010 Rev 1
logo
Unisonic Technologies
LR1112G-XX-AE5-R UTC-LR1112G-XX-AE5-R Datasheet
177Kb / 6P
   Current limit protection
logo
Texas Instruments
PT5071-12V TI1-PT5071-12V Datasheet
150Kb / 4P
[Old version datasheet]   Output Current Limit
logo
Solid State Optronic
AD4C111-L SSOUSA-AD4C111-L_15 Datasheet
221Kb / 5P
   Current Limit Protection
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


Scheda tecnica Scarica

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEETIT.COM
Lei ha avuto il aiuto da alldatasheet?  [ DONATE ] 

Di alldatasheet   |   Richest di pubblicita   |   contatti   |   Privacy Policy   |   scambio Link   |   Ricerca produttore
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