LT3592EDDB#PBF Linear Technology, LT3592EDDB#PBF Datasheet - Page 14

• Manufacturer Part Number: LT3592EDDB#PBF
• Description: IC, LED DRIVER, BUCK, DFN-10
• Manufacturer: Linear Technology

Specifications of LT3592EDDB#PBF

• Led Driver Application: Automotive, Industrial Lighting
• No. Of Outputs: 1
• Output Current: 500mA
• Output Voltage: 30V
• Input Voltage: 3.6V To 36V
• Dimming Control Type: PWM
• Topology: Buck
• Operating Supply Voltage (typ): 5/9/12/15/18/24V
• Number Of Segments: 2
• Operating Temperature (min): -40C
• Operating Temperature (max): 125C
• Operating Temperature Classification: Automotive
• Package Type: DFN EP
• Pin Count: 10
• Mounting: Surface Mount
• Operating Supply Voltage (max): 36V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

LT3592
APPLICATIONS INFORMATION
BOOST Pin Considerations
The capacitor C3 and an internal Schottky diode from
the CAP to the BOOST pin are used to generate a boost
voltage that is higher than the input voltage. An external
fast switching Schottky diode (such as the BAS40) can
be used in parallel with the internal diode to make this
boost circuit even more effective. In most cases, a 0.1μF
capacitor works well for the boost circuit. The BOOST pin
must be at least 2.5V above the SW pin for best effi ciency.
For output voltages above 12V, use a 0.1μF cap and an
external boost diode (such as a BAS40) connected in
14
BATT
CAP
V
IN
LT3592
BOOST
GND
Figure 4. Transient Load Response of the LT3592 with Different Output Capacitors
SW
DA
(5a)
OPTIONAL
C3
Figure 5. Two Circuits for Generating the Boost Voltage
D2
V
V
3592 F05a
V
V
I
I
OUT
OUT
LED
LED
SW
SW
C = 4.7μF
C = 10μF
100μs/DIV
100μs/DIV
parallel with the internal Schottky diode, anode to CAP
and cathode to BOOST. For outputs between 3.3V and
12V, the 0.1μF cap and the internal boost diode will be
effective. For 3V to 3.3V outputs, use a 0.22μF capacitor.
For output between 2.5V and 3V, use a 0.47μF capacitor
and an external Schottky diode connected as shown in
Figure 5a. For lower output voltages, the external boost
diode’s anode can be tied to the input voltage. This con-
nection is not as effi cient as the others because the BOOST
pin current comes from a higher voltage. The user must
also be sure that the maximum voltage rating of the BOOST
pin is not exceeded.
BATT
3592 F04
D2
CAP
V
IN
BOOST
LT3592
GND
SW
DA
(5b)
C3
3592 F05b
3592fc