ZXSC300E5TA Diodes Zetex, ZXSC300E5TA Datasheet - Page 9

• Manufacturer Part Number: ZXSC300E5TA
• Description: IC LED DRVR WHITE BCKLGT SOT23-5
• Manufacturer: Diodes Zetex
• Type: Backlight, White LEDr

Specifications of ZXSC300E5TA

• Constant Current: Yes
• Topology: Step-Up (Boost)
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: Backlight, Flash/Torch
• Type - Secondary: High Brightness LED (HBLED), White LED
• Frequency: 200kHz
• Voltage - Supply: 0.8 V ~ 8 V
• Mounting Type: Surface Mount
• Package / Case: SOT-23-5, SC-74A, SOT-25
• Operating Temperature: -40°C ~ 85°C
• Current - Output / Channel: 3.6mA
• Internal Switch(s): Yes
• Efficiency: 94%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Other names: ZXSC300E5TR

P
I
Output Power Calculation
By making the above assumptions for inductance and
peak current the output power can be determined by:
Note: V
drop
where
T
and
T
and
Layout of Maximum battery life solution
ISSUE 4 - SEPTEMBER 2007
MIN
OUT
OFF
ON
=
=
=
≅ 1.7µs (internally set by ZXSC300)
Top Copper
I
Bottom Copper
PK
T
(V
OFF
OUT
−
OUT
(
( V
V
V
= output voltage + Schottky rectifier voltage
V
OUT
IN
OUT
IN
) (
x I
2
−
- V
V
PK
IN
L
)
IN
+
)
I
MIN
x T
)
OFF
x
(
T
ON
T
+
OFF
T
OFF
)
9
F
Operating frequency can be derived by:
Capacitor selection
For pulsed operation, as in the maximum battery life
solution, no capacitors are required at the output to
the LED. For rectified operation, as in the maximum
brightness solution, a small value ceramic capacitor
is required, typically 2.2uF.
Generally an input capacitor is not required, but a
small ceramic capacitor may be added to aid EMC,
typically 470nF to 1uF.
Demonstration board
A demonstration board for the Maximum battery life
solution, is available upon request. These can be
obtained through your local Zetex office or through
Zetex web pages. For all reference designs Gerber
files and bill of materials can be supplied.
=
Drill Holes
Silk Screen
(
T
ON
+
1
T
OFF
)
ZXSC300