DC2279A Analog Devices

DEMO MANUAL DC2279A LT3088EDD 800mA Single Resistor Rugged Linear Regulator DESCRIPTION DC2279A is a linear regulator evaluation board featuring reverse battery protection, reverse current protection, LT 3088EDD, which is a 36V , 800mA, rugged single internal current limit and thermal limit. IN resistor programmable linear regulator. DC2279A uses the LT3088EDD which is an 8-lead The demo circuit operates over an input range of 1.6V to (3mm3mm) plastic DFN package with an exposed pad on 36V. The LT3088 has a maximum output current of 800mA. the bottom-side of the IC for better thermal performance. A key feature of the IC is the extended safe operation area These features make DC2279A an ideal circuit for surface- (SOA). The IC also features paralleled capability for higher mount power supplies, rugged industrial power supplies, output current or heat spreading. low output voltage supplies, a post regulator for switching supplies and intrinsic safety applications. This device allows one single resistor to program output voltage to any level between 0V and 34.5V if the load Design files for this circuit board are available at current is larger than 2mA. Built-in protection includes DEMO MANUAL DC2279A PERFORMANCE SUMMARY Specifications are at T = 25C A V (V) V (V) IN OUT CONDITIONS I (mA) MIN TYP MAX* MIN TYP MAX OUT Shunt at 1.2V for JP1 100 2.41 36.0 1.17 1.20 1.25 800 2.80 5.6 1.17 1.20 1.25 Shunt at 1.5V for JP1 100 2.71 36.0 1.46 1.50 1.56 800 3.10 6.0 1.46 1.50 1.56 Shunt at 1.8V for JP1 100 3.01 36.0 1.75 1.80 1.88 800 3.40 6.3 1.75 1.80 1.88 Shunt at 2.5V for JP1 100 3.71 36.0 2.43 2.50 2.60 800 4.10 7.0 2.43 2.50 2.60 Shunt at 3.3V for JP1 100 4.51 36.0 3.20 3.30 3.44 3.44 800 4.90 7.8 3.20 3.30 Shunt at 5.0V for JP1 100 6.21 36.0 4.85 5.00 5.20 800 6.60 9.5 4.85 5.00 5.20 *The maximum input voltage for 800mA load current is set by the 75C temperature rise of LT3088 on the demo circuit. Higher input voltage can be reached if larger copper area or force-air cooling is applied. QUICK START PROCEDURE DC2279A is easy to set up to evaluate the performance 3. Turn on the power at the V . IN of the LT3088. Refer to Figure 1 for proper measurement NOTE: Make sure that the V voltage does not ex- IN equipment setup and follow the procedure below. ceed36V. NOTE: When measuring the input or output voltage ripple, 4. Check for the proper output voltages. care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the input or output voltage NOTE: If there is no output, temporarily disconnect the ripple by touching the probe tip directly across the terminals load to make sure that the load is not set too high or of the input or output capacitors. See Figure 2 for proper is shorted. scope probe technique. 5. Once the proper output voltages are established, ad- 1. Use JP1 to set the desired output voltage. just the loads within the operating range and observe the output voltage regulation, efficiency and other 2. With power off, connect the input power supply to V IN parameters. and GND. NOTE: Make sure that the power dissipation is limited below the thermal limit. dc2279af 2