Datenblatt-Suchmaschine für elektronische Bauteile
  German  ▼
ALLDATASHEETDE.COM

X  

LM2795 Datenblatt(PDF) 11 Page - Texas Instruments

Teilenummer LM2795
Bauteilbeschribung  LM2794 /LM2795 Current Regulated Switched Capacitor LED Supply with Analog and PWM Brightness Control
Download  24 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Hersteller  TI1 [Texas Instruments]
Direct Link  http://www.ti.com
Logo TI1 - Texas Instruments

LM2795 Datenblatt(HTML) 11 Page - Texas Instruments

Back Button LM2795 Datasheet HTML 7Page - Texas Instruments LM2795 Datasheet HTML 8Page - Texas Instruments LM2795 Datasheet HTML 9Page - Texas Instruments LM2795 Datasheet HTML 10Page - Texas Instruments LM2795 Datasheet HTML 11Page - Texas Instruments LM2795 Datasheet HTML 12Page - Texas Instruments LM2795 Datasheet HTML 13Page - Texas Instruments LM2795 Datasheet HTML 14Page - Texas Instruments LM2795 Datasheet HTML 15Page - Texas Instruments Next Button
Zoom Inzoom in Zoom Outzoom out
 11 / 24 page
background image
¸¸
¹
·
¨¨
©
§
¸¸
¹
·
¨¨
©
§
Amps
1
10
*
188
BRGT
V
*
+
385
.
0
.
0
SET
R
*
o
MirrorRati
OFFSET
V
+
BRGT
V
385
.
0
*
R
SET
LED =
I
LED =
I
LM2794, LM2795
www.ti.com
SNVS168L – JANUARY 2002 – REVISED MAY 2013
For most applications, ceramic capacitors with X7R or X5R temperature characteristic are preferred for use with
the LM2794/5. These capacitors have tight capacitance tolerance (as good as ±10%), hold their value over
temperature (X7R: ±15% over
−55°C to 125°C; X5R: ±15% over −55°C to 85°C), and typically have little voltage
coefficient. Capacitors with Y5V or Z5U temperature characteristic are generally not recommended for use with
the LM2794/5. Capacitors with these temperature characteristics typically have wide capacitance tolerance
(+80%,
−20%), vary significantly over temperature (Y5V: +22%, −82% over −30°C to +85°C range; Z5U: +22%,
−56% over +10°C to +85°C range), and have poor voltage coefficients. Under some conditions, a nominal 1µF
Y5V or Z5U capacitor could have a capacitance of only 0.1µF. Such detrimental deviation is likely to cause Y5V
and Z5U capacitors to fail to meet the minimum capacitance requirements of the LM2794/5. Table 1 lists
suggested capacitor suppliers for the typical application circuit.
Table 1. Ceramic Capacitor Manufacturers
Manufacturer
Contact
TDK
www.component.tdk.com
Murata
www.murata.com
Taiyo Yuden
www.t-yuden.com
LED SELECTION
The LM2794/5 is designed to drive LEDs with a forward voltage of about 3.0V to 4.0V. The typical and maximum
diode forward voltage depends highly on the manufacturer and their technology. Table 2 lists two suggested
manufacturers. Forward current matching is assured over the LED process variations due to the constant current
output of the LM2794/5.
Table 2. White LED Selection
Manufacturer
Contact
Osram
www.osram-os.com
Nichia
www.nichia.com
ISET AND BRGT PINS
An external resistor, RSET, is connected to the ISET pin to set the current to be mirrored in each of the LED
outputs. The internal current mirror sets each LED output current with a 10:1 ratio to the current through RSET.
The current mirror circuitry matches the current through each LED to within 0.5%.
In addition to RSET, a voltage may be applied to the VBRGT pin to vary the LED current. By adjusting current with
the Brightness pin (BRGT), the brightness of the LEDs can be smoothly varied.
Applying a voltage on BRGT between 0 to 3 volts will linearly vary the LED current. Voltages above 3V do not
increase the LED current any further. The voltage on the VBRGT pin is fed into an internal resistor network with a
ratio of 0.385. The resulting voltage is then summed with a measured offset voltage of 0.188V, which comes
from the reference voltage being fed through a resistor network (See Functional Block Diagram). The brightness
control circuitry then uses the summed voltage to control the voltage across RSET. An equation for approximating
the LED current is:
ILED CURRENT SELECTION PROCEDURES
The following procedures illustrate how to set and adjust output current levels. For constant brightness or analog
brightness control, go to “Brightness control using BRGT”. Otherwise refer to “Brightness control using PWM”.
Brightness Control Using PWM
1. Set the BRGT pin to 0V.
Copyright © 2002–2013, Texas Instruments Incorporated
Submit Documentation Feedback
11
Product Folder Links: LM2794 LM2795


Ähnliche Teilenummer - LM2795

HerstellerTeilenummerDatenblattBauteilbeschribung
logo
Texas Instruments
LM2795 TI1-LM2795 Datasheet
1Mb / 21P
[Old version datasheet]   Current Regulated Switched Capacitor LED Supply with Analog and PWM Brightness Control
logo
National Semiconductor ...
LM27951 NSC-LM27951 Datasheet
605Kb / 10P
   White LED Adaptive 1.5X/1X Switched Capacitor Current Driver
logo
Texas Instruments
LM27951 TI1-LM27951 Datasheet
873Kb / 20P
[Old version datasheet]   White LED Adaptive 1.5/1 Switched-Capacitor Current Driver
logo
National Semiconductor ...
LM27951SD NSC-LM27951SD Datasheet
605Kb / 10P
   White LED Adaptive 1.5X/1X Switched Capacitor Current Driver
logo
Texas Instruments
LM27951SD TI1-LM27951SD Datasheet
873Kb / 20P
[Old version datasheet]   White LED Adaptive 1.5/1 Switched-Capacitor Current Driver
More results

Ähnliche Beschreibung - LM2795

HerstellerTeilenummerDatenblattBauteilbeschribung
logo
Texas Instruments
LM2794 TI1-LM2794_14 Datasheet
1Mb / 21P
[Old version datasheet]   Current Regulated Switched Capacitor LED Supply with Analog and PWM Brightness Control
logo
National Semiconductor ...
LM2794 NSC-LM2794 Datasheet
487Kb / 16P
   Current Regulated Switched Capacitor LED Supply with Analog and PWM Brightness Control
LM2791 NSC-LM2791 Datasheet
226Kb / 11P
   Current Regulated Switched Capacitor LED Driver with Analog Brightness Control
LM2792 NSC-LM2792 Datasheet
204Kb / 10P
   Current Regulated Switched Capacitor LED Driver with Analog Brightness Control
logo
Texas Instruments
LM2791 TI1-LM2791 Datasheet
1Mb / 18P
[Old version datasheet]   LM2791 Current Regulated Switched Capacitor LED Driver with Analog Brightness Control
TPS61061 TI-TPS61061 Datasheet
609Kb / 22P
[Old version datasheet]   CONSTANT CURRENT LED DRIVER WITH DIGITAL AND PWM BRIGHTNESS CONTROL
TPS60231 TI-TPS60231 Datasheet
409Kb / 16P
[Old version datasheet]   WHITE LED CHARGE PUMP CURRENT SOURCE WITH PWM BRIGHTNESS CONTROL
TPS60230 TI1-TPS60230_14 Datasheet
989Kb / 21P
[Old version datasheet]   WHITE LED CHARGE PUMP CURRENT SOURCE WITH PWM BRIGHTNESS CONTROL
logo
Integrated Silicon Solu...
IS31BL3230-QFLS2-TR ISSI-IS31BL3230-QFLS2-TR Datasheet
270Kb / 12P
   8 CHANNELS CONSTANT CURRENT LED DRIVER WITH PWM BRIGHTNESS CONTROL
logo
SG Micro Corp
SGM3124 SGMICRO-SGM3124 Datasheet
378Kb / 17P
   White LED Charge Pump Current Source with PWM Brightness Control
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


Datenblatt Download

Go To PDF Page


Link URL




Privatsphäre und Datenschutz
ALLDATASHEETDE.COM
War ALLDATASHEET hilfreich?  [ DONATE ] 

Über Alldatasheet   |   Werbung   |   Kontakt   |   Privatsphäre und Datenschutz   |   Linktausch   |   Hersteller
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