ZLED7015ZI1R ZMDI, ZLED7015ZI1R Datasheet - Page 17

• Manufacturer Part Number: ZLED7015ZI1R
• Description: LED Lighting Drivers LED driver
• Manufacturer: ZMDI

Specifications of ZLED7015ZI1R

• Rohs: yes
• Input Voltage: 6 V to 30 V
• Maximum Supply Current: 2 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: MSOP-10
• Minimum Operating Temperature: - 40 C

3
The following sections cover selection of the external components shown in the typical application on page 2.
3.1
Recommendation: Use precision resistors (±1% or better tolerance) for the R
control of the LED current.
See section 2.2.1 for the equation for selecting the value of R
3.2
Designing the circuit so that the current through inductor L
typically gives the best performance due to improved load regulation and reduced output ripple. Select an
inductor that has a saturation current and a current rating greater than the mean input current.
The inductor value selection requires trade-offs between unwanted ripple current and parasitic effects. A
larger value inductor reduces inductor ripple current, resulting in less output ripple voltage; however, higher
values also increase parasitic resistance, which can degrade performance. For most applications, a 10µH
inductor with a saturation current >2.5A is adequate. See section 7.4 for layout restrictions.
3.3
The input capacitors C
larger low-ESR electrolytic capacitor for C
input voltage plus a safety margin for C
3.4
The output capacitors C
low-ESR electrolytic capacitor for C
voltage plus a safety margin for C
3.5
For the diode D
maximum operating voltage and temperature to ensure maximum efficiency and performance.
Important: Choose diodes with a continuous current rating higher than the maximum output load current and a
peak current rating above the peak coil current. When operating above 85°C, the reverse leakage of the diode
must be addressed because it can cause excessive power dissipation in the diode, especially when the output
voltage is relatively high. Its reverse breakdown voltage must be greater than the over-voltage protection level
V
Note: Silicon diodes have higher forward voltage and higher voltage overshoot before they start conducting,
which can increase the peak voltage on the LX output. Ensure that the total voltage appearing on the LX pin,
including supply ripple, is within the specified range (see Table 1.1).
3.6
For the VDD input, connect resistor R
ground. Recommendations: use 1µF for C
with input voltages < 8V.
For the VP pin, connect a 10µF ceramic
If the EN pin is not used, connect a 100kΩ resistor to the positive power supply (R
to float.
Data Sheet
December 20, 2011
OVP
ZLED7015
1.0MHz Boost Converter with Internal 35V Switch
(see section 4.2).
Application Circuit Design
External Component – R
External Component – Inductor L
External Components – Input Decoupling Capacitors C
External Component –Output Capacitors C
External Component – Diode D
Additional External Components
1
© 2011 Zentrum Mikroelektronik Dresden AG — Rev. 1.00
All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without
the prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
, select a high-speed, low-capacitance Schottky diode with low reverse leakage at the
1
2
and C
and C
IN
OUT
minimize the input voltage noise and ripple. Recommendation: use a 22µF or
2
.
minimize the output voltage ripple. Recommendation: use a 22µF or larger
OUT
S
VDD
1
in parallel with a 1µF ceramic capacitor rated at greater than the output
.
bypass capacitor to ground (C
to the positive power supply and connect ceramic capacitor C
IN
VDD
1
in parallel with a 1µF ceramic capacitor rated at greater than the
; use 300Ω for R
1
2
and C
S
, which sets the nominal current output.
1
VDD
is always above 0V (i.e., continuous mode)
OUT
with input voltages ≥ 8V, use 50Ω for R
VP
1
).
and C
S
IN
resistor to ensure accurate
EN
). Do not allow the EN pin
17 of 22
VDD
VDD
to