LED7707TR STMicroelectronics, LED7707TR Datasheet - Page 37
![IC LED DRIVR WHT BCKLT 24-VFQFPN](/photos/7/37/73763/led7707tr_sml.jpg)
LED7707TR
Manufacturer Part Number
LED7707TR
Description
IC LED DRIVR WHT BCKLT 24-VFQFPN
Manufacturer
STMicroelectronics
Type
Backlight, White LEDr
Datasheet
1.LED7707TR.pdf
(47 pages)
Specifications of LED7707TR
Topology
PWM, Step-Up (Boost)
Number Of Outputs
6
Internal Driver
Yes
Type - Primary
Backlight
Type - Secondary
White LED
Frequency
250kHz ~ 1MHz
Voltage - Supply
4.5 V ~ 36 V
Voltage - Output
36V
Mounting Type
Surface Mount
Package / Case
24-VFQFN, 24-VFQFPN
Operating Temperature
0°C ~ 85°C
Current - Output / Channel
85mA
Internal Switch(s)
Yes
High Level Output Current
85 mA
Operating Supply Voltage
4.5 V to 36 V
Maximum Supply Current
1 mA
Maximum Power Dissipation
2.3 W
Maximum Operating Temperature
+ 150 C
Mounting Style
SMD/SMT
Minimum Operating Temperature
- 40 C
For Use With
497-10044 - BOARD EVAL LCD BACKLIGHT LED7707
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Efficiency
-
Lead Free Status / Rohs Status
Details
Other names
497-8492-2
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LED7707TR
Manufacturer:
ST
Quantity:
12 000
Company:
Part Number:
LED7707TR
Manufacturer:
STMicroelectronics
Quantity:
10 000
LED7707
Note:
In order to estimate also the efficiency, other contributions to the power dissipation must be
added to P
Equation 47
where V
Equation 48
where DCR = 80 mΩ (typical DCR of the recommended inductors).
Therefore the total dissipated power is:
Equation 49
Considering the input power as the result of input voltage multiplied by the input current, the
estimated efficiency is:
Equation 50
It is important to remind that the previous calculations consider the worst case, especially for
the power dissipated on the current generators.
Statistical analysis (confirmed by bench measurements) shows that the series connection of
more LEDs on each channel leads to compensation effects.
The hypothesis 3 above mentioned is thus rather unlikely.
Therefore P
F, Diode
D, tot
GEN
= 0.4 V
(which represents only the power dissipated by the device), that is:
is significantly lower and the overall efficiency is typically around 90 %.
P
DISS
P
DISS
,
TOTAL
P
DISS
,
Ind
=
,
Diode
η
=
P
DCR
=
, D
P
tot
=
IN
+
V
⋅
−
I
, F
P
2
Ind
P
P
Diode
DISS
DISS
,
IN
RMS
,
Diode
,
⋅
TOT
I
≅
IN
DCR
⋅
+
D
=
P
2
. 0
DISS
=
⋅
862
I
2
IN
133
,
Ind
=
mW
63
=
. 1
mW
316
Application information
W
37/47