Advertisement
Quick Links
QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1286
DESCRIPTION
Demonstration circuit 1286A is DC/DC boost converter
featuring the LTC ® 3862EGN constant frequency current
mode boost controller. The DC1286A-A operates over 5V
to 36V input and provides 2A-5A of output current at
48V output. The DC1286A-B operates over 8V to 36V
input and provides 3A-5A of output current at 48V out-
put. The 200kHz constant frequency operation results in
small and efficient circuit. The converter provides high
output voltage accuracy (typically ±3%) over wide load
range with no minimum load requirement.
Table 1. Performance Summary
PARAMETER
Minimum Input Voltage
DC1286A-A
DC1286A-B
Maximum Input Voltage
V OUT
Typical Output Ripple V OUT
Nominal Switching Frequency
QUICK START PROCEDURE
Demonstration circuit 1286A is easy to set up to evalu-
ate the performance of the LTC3862. For proper meas-
urement equipment setup refer to Figure 1 and follow
the procedure below:
When measuring the input or output voltage rip-
NOTE:
ple, care must be taken to minimize the length of oscil-
loscope probe ground lead. Measure the input or output
voltage ripple by connecting the probe tip directly across
the VIN or VOUT and GND terminals as shown in
Figure 2.
With power off, connect the input power supply to Vin
1.
and GND.
48V OUTPUT BOOST CONVERTER
LTC3862EGN, LTC3862EGN-1
The demonstration circuit can be easily modified to gen-
erate different output voltages. Please consult LTC fac-
tory for details.
The DC1286A has small circuit footprint. It is a high per-
formance and cost effective solution for Telecom, Auto-
motive and Power Over Ethernet applications.
Design files for this circuit board are available. Call
the LTC factory.
PowerPath is a trademark of Linear Technology Corporation
CONDITION
I OUT = 0A to 2A
I OUT = 0A to 5A
V IN = 12V, I OUT = 3A
V IN = 12V, I OUT = 4A
Check the Vcc Bias voltage-setting jumper JP5. Move
2.
it into Vin position if required.
Turn the input power source on and slowly increase
3.
the input voltage. Be careful not to exceed 36V.
Make sure that the input voltage Vin does not
NOTE:
exceed 36V. If higher operating voltage is required,
power components with higher voltage ratings should
be used. Also, Jumper JP5 will have to be moved to
12V position.
Check for the proper output voltage of 48V.
4.
If there is no output, temporarily disconnect the load
to make sure that the load is not set too high.
VALUE
5V
8V
36V
48V ±3%
400mV P–P
200kHz
1
Advertisement
Related Manuals for Linear DC1286A-B
Summary of Contents for Linear DC1286A-B
- Page 1 36V input and provides 2A-5A of output current at The DC1286A has small circuit footprint. It is a high per- 48V output. The DC1286A-B operates over 8V to 36V formance and cost effective solution for Telecom, Auto- input and provides 3A-5A of output current at 48V out- motive and Power Over Ethernet applications.
- Page 2 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1286 48V OUTPUT BOOST CONVERTER OPTIONAL BIAS CIRCUIT Once the proper output voltage is established, adjust the load and observe the output voltage regulation, ripple voltage, efficiency and other parameters. The demo board DC1286A can be used for boosting higher input voltages as well.
-
Page 3: Changing The Output Voltage
The DC1286A output current capability depends on the input voltage and proper cooling. Typical performance of DC1286A-A is shown in Figure 3. The efficiency of DC1286A-B which is equipped with 10V gate drive version of PWM controller LTC3862-1 is shown in Figure 4. - Page 4 12V in 24V in Iout [A] Figure 4. DC1286A-B Efficiency OUTPUT LOAD STEP RESPONSE The load step response of DC1286A-A is very fast even though relatively small amount of output capacitance is present at the output. If higher load steps need to be handled more output capacitance can be added in order to keep the voltage transients at the desired level.
- Page 5 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 1286 48V OUTPUT BOOST CONVERTER...
- Page 6 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Analog Devices Inc. DC1286A-B DC1286A-A...