Datasheet
Table Of Contents
- Figure 1. Typical application circuit
- 1 Pin settings
- 2 Maximum ratings
- 3 Electrical characteristics
- 4 Functional description
- 5 Application notes - buck conversion
- 5.1 Closing the loop
- 5.2 GCO(s) control to output transfer function
- 5.3 Error amplifier compensation network
- 5.4 LED small signal model
- 5.5 Total loop gain
- 5.6 Compensation network design
- 5.7 Example of system design
- 5.8 Dimming operation
- 5.9 Component selection
- 5.10 Layout considerations
- 5.11 Thermal considerations
- 5.12 Short-circuit protection
- 5.13 Application circuit
- 6 Application notes - alternative topologies
- 7 Package mechanical data
- 8 Ordering information
- 9 Revision history
LED5000 Application notes - buck conversion
Doc ID 023951 Rev 1 31/51
Figure 19. constant current protection triggering hiccup mode
5.13 Application circuit
Figure 20. Evaluation board application circuit
The network D3, R4, RS implements an inexpensive overvoltage protection. R4 effect can
be neglected during normal operation since the FB biasing current is negligible (tens of nA,
see
Table 5: Electrical characteristics
) but it limits the current flowing in the Zener diode D3.
In case the load is disconnected or in case of open LED:
AM13503v1
small signal
power plane
RS
R56
TP6
GND
R1 10k
R3
24.9K
C7
1uF
50V
TP1
DIM
C6 100nF
TP4
VLED+
JP1
D3 BZX384-C39
C5
22pF
TP8INH
TP5
VLED-
C4
470pF
TP3
GND
JP2
C1
10uF
50V
TP2
VIN
U1 LED5000
SW
8
VIN
7
BOOT
1
EP
EP
DIM
2
INH
3
GND
6
COMP
4
FB
5
D1STPS3L60U
2
1
C3
100nF
50V
C2
10uF
50V
R2
NM
C8
NM
D2
BZX384-4V7
R4 47k
L1 47uH
AM13504v1