HVLED805TR STMicroelectronics, HVLED805TR Datasheet - Page 21
HVLED805TR
Manufacturer Part Number
HVLED805TR
Description
IC LED DRVR ACDC OFFLINE 16NSOIC
Manufacturer
STMicroelectronics
Type
General Purposer
Datasheet
1.HVLED805TR.pdf
(29 pages)
Specifications of HVLED805TR
Constant Current
Yes
Constant Voltage
Yes
Topology
AC DC Offline Switcher, PWM
Number Of Outputs
1
Internal Driver
Yes
Type - Primary
General Purpose
Voltage - Supply
11.5 V ~ 23 V
Mounting Type
Surface Mount
Package / Case
*
Internal Switch(s)
Yes
Efficiency
*
Operating Supply Voltage
11.5 V to 23 V
Maximum Supply Current
1.4 mA
Maximum Power Dissipation
0.9 W
Maximum Operating Temperature
+ 125 C
Mounting Style
SMD/SMT
Minimum Operating Temperature
- 40 C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Voltage - Output
-
Frequency
-
Operating Temperature
-
Current - Output / Channel
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Other names
497-10810-2
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
HVLED805TR
Manufacturer:
TSC
Quantity:
6 000
Part Number:
HVLED805TR
Manufacturer:
ST
Quantity:
20 000
HVLED805
Figure 17. Feedforward compensation: internal schematic
During MOSFET’s ON-time the current sourced from DMG pin is mirrored inside the
“ Feedforward Logic ” block in order to provide a feedforward current, I
Such “feedforward current” is proportional to the input voltage according to the formula:
Equation 9
Where m is the primary-to-auxiliary turns ratio.
According to the schematic, the voltage on the non-inverting comparator will be:
Equation 10
The offset introduced by feedforward compensation will be:
Equation 11
As R
Equation 12
FF
Aux
>>R
Rdmg
SENSE
DMG
Rfb
, the previous one can be simplified as:
V
F eedforward
V = R
OFFSET
Doc ID 18077 Rev 1
Logic
(-)
V
SENSE D
=
OFFSET
I
m
FF
.
⋅
V
⋅
R
=
I +I
IN
dmg
m
IF F
=
FF
⋅
V
m
V
R
⋅
⋅
IN
IN
(
(
dmg
⋅
R
R +R
R
Block
⋅
CC
FF
FF
R
dmg
FF
+
R
SENSE
SENSE
+
-
)
CC
)
Application information
FF
RFF
.
LOGIC
PWM
SO URCE
DRAIN
Rsense
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