ZXLD1370EST16TC Diodes Inc, ZXLD1370EST16TC Datasheet - Page 15

• Manufacturer Part Number: ZXLD1370EST16TC
• Description: LED Drivers 6V TO 60V 11uA
• Manufacturer: Diodes Inc

Specifications of ZXLD1370EST16TC

• High Level Output Current: 18 mA
• Operating Supply Voltage: 6 V to 60 V
• Maximum Supply Current: 11 uA
• Maximum Operating Temperature: + 125 C
• Package / Case: TSSOP-16 EP
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

This will result in:
ZXLD1370
Document number: DS32165 Rev. 4 - 2
R
Setting R
Table 1 shows typical resistor values used to determine GI
Applications Information
Table 1
Recommended inductor values for the ZXLD1370 are in the range 22 μH to 100 μH. The chosen coil should have a
saturation current higher than the peak sensed current and a continuous current rating above the required mean sensed
current by at least 50%.
The inductor value should be chosen to maintain operating duty cycle and switch 'on'/'off' times within the recommended
limits over the supply voltage and load current range.
The frequency compensation mechanism inside the chip tends to keep the frequency within the range 300kHz – 400kHz in
most of the operating conditions. Nonetheless, the controller allows for higher frequencies when either the number of LEDs
or the input voltage increases.
The graphs below can be used to select a recommended inductor to maintain the ZXLD1370 switching frequency within a
predetermined range when used in different topologies.
Buck inductor selection:
INDUCTOR/FREQUENCY SELECTION
GI
GI ratio
2
0.25
0.35
0.45
0.2
0.3
0.4
0.5
=
R
R
GI1
GI
s
( 1
= 33kΩ gives
=
V
V
ADJ
(R
GI
GI
100kΩ
30kΩ
33kΩ
39kΩ
30kΩ
51kΩ
30kΩ
RGI1
R
1
−
GI
+
) 1
15
13
11
R
1
9
7
5
3
1
=
Figure 19. 1.5A Buck mode inductor selection for target frequency of 400 kHz
GI
110
0
) 2
k
225
Ω
I
LED
L=10µH
mV
(Continued)
120kΩ
100kΩ
150kΩ
=
10
91kΩ
56kΩ
62kΩ
30kΩ
RG2
150
L=22µH
ZXLD1370 Buck Mode 1.5A Minimum Recommended Inductor
m
Ω
20
www.diodes.com
Target Switching Frequency - 400kHz
L=33µH
Supply Voltage (V)
RATIO
15 of 36
with E24 series resistors
30
40
Diodes Incorporated
A Product Line of
L=47µH
50
60
© Diodes Incorporated
ZXLD1370
March 2011