ZLED7520ZI1R ZMDI, ZLED7520ZI1R Datasheet - Page 20

• Manufacturer Part Number: ZLED7520ZI1R
• Description: LED Lighting Drivers LED driver
• Manufacturer: ZMDI

Specifications of ZLED7520ZI1R

• Rohs: yes
• Input Voltage: 6 V to 40 V
• Operating Frequency: 1 MHz
• Maximum Supply Current: 600 uA
• Output Current: 0.75 A
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• Package / Case: DFN-5
• Minimum Operating Temperature: - 40 C
• Power Dissipation: 500 mW

Where:
Example: For an application with 3 LEDs with 3.2V forward voltage each driven at 0.33A and supplied with
rectified 24VAC, a minimum bypass capacitor C1 of 220µF or 330µF might be adequate. Compared to the
calculation, a safety margin of about 50% must be added to consider temperature effects and aging.
A second function of C1 is to bypass the current ripple of the switching converter and thus prevent it from
disturbing a stable IC supply or backlash on the power supply circuit. For this reason, even in DC-supplied
applications, the use of an adequate C1 might be useful. The defining parameters are now as shown in
equation (11):
Where:
C
I
t
I
t
V
Data Sheet
August 12, 2011
C
C
AVG
D
AVG
ON
1
V
RIPPLE
1
1
MIN
ZLED7520
High Current 40V LED Driver with Internal Switch
MIN
MIN
MAX
Symbol
Symbol
I
AVG
24
I
AVG
V
V
V
MAX
. 0
RIPPLE
t *
33
*
t *
D
ON
A
2
© 2011 Zentrum Mikroelektronik Dresden AG — Rev. 1.2
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.
*
10
3
V
Average nominal LED string current assuming that the contribution of the IC supply current is
negligible.
Discharge time at given AC frequency. Will be a maximum of 10ms (½ period duration) at 50Hz.
Peak rectified supply voltage minus LED string forward voltage or minimum ZLED7x20 supply
voltage, whichever is greater.
Average nominal LED string current.
On time of the internal MOSFET output switch.
Note: t
Permissible voltage ripple on the supply voltage.
I
F
MAX
*
ms
*
3
D
2 .
LX
f *
V
ON
LX
must be longer than t
135
F
ONmin
=200ns.
Description
Description
(10)
(11)
(9)
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