SLUAA69 July 2020 – MONTH TPS548D22
The power level of an LED display module varies from 100 W to 300 W by different pixel pitches. The common power levels for small pixel pitch LED signage in the market are 110 W, 150 W and 220 W. Design parameters and recommended devices are listed in Table 4-1 based on different power levels.
TPS548B22 and TPS548D22 are pin-to-pin, 25 A and 40 A, synchronous buck converter devices. TPS549B22 and TPS549D22 are the same series devices with an additional PMBus? function for programming. For powering an LED display, the output voltage can be set or dynamically adjusted through PMBus? to further optimize the design by adjusting the cathode voltage to more precisely match the red LED forward voltage. Since a voltage drop on the path varies in current (as determined by brightness), the red LED forward voltage may drop or increase if a fixed output voltage is applied.
|
Design Parameters |
Specifications | ||
|---|---|---|---|
|
110 W |
150 W |
220 W | |
|
Input Voltage |
4.2 V |
4.2 V |
4.2 V |
|
Output Voltage |
1 V |
1 V |
1 V |
|
Red LED Forward Voltage |
3.2 V |
3.2 V |
3.2 V |
|
Red LED Total Load Current |
15 A |
20 A |
30 A |
|
Blue and Green LED Forward Voltage |
4.2 V |
4.2 V |
4.2 V |
|
Blue and Green Total Load Current |
15 A |
20 A |
30 A |
|
Recommended Device | |||
|
Recommended Device With PMBus? | |||
This series of devices support soft-start, pre-bias start up, UVLO protection with external adjustment by precise enable hysteresis, and fault protection (OVP, UVP, OCP, OTP). In addition, hiccup mode or latch-off mode can be chosen by external resistor setting. The next sections will discuss some key functionality with TPS548D22. For more details, refer to the TPS548D22 1.5-V to 16-V VIN, 4.5-V to 22-V VDD, 40-A SWIFT? Synchronous Step-Down Converter with Full Differential Sense Data Sheet.