Jessicale Posted April 24, 2017 Report Share Posted April 24, 2017 Hi, I want to ask for your help on my L5973D. I used to use L5973D to produce voltage of 3.3V/4.2V according to the typical circuit in the datasheet. The figures are same while the feedback resistance are different. The input is 24V DC. They worked well without anything wrong. (Test application circuit in the datasheet) However, I met some problems when I want to produce 5V voltage according to the circuit above. I tried to turn the R1 into 10K. Theoretically,it will produce 5V, but when I connected it with 24V power,L5973D burned up. In the same circuit, the voltage is 3.3V when R1 is 5.6K. It worked well. I am wondering why...So I’m here to ask for your help.Sorry for my poor English,but can anyone give me some suggestions? Here are some details of L5973D: Series:L5973 Operating-Temperature: -40°C ~ 150°C (TJ) Mounting-Type: Surface Mount Output-Type: Adjustable Function: Step-Down Supplier-Device-Package: 8-HSOP Number-of-Outputs: 1 Topology: Buck Frequency-Switching: 250kHz Current-Output: 2.5A Output-Configuration: Positive Voltage-Output-Min-Fixed: 1.235V Voltage-Output-Max: 35V Synchronous-Rectifier: No Voltage-Input-Min: 4V Voltage-Input-Max: 36V Output-Voltage: 35 V Input-Voltage-MAX: 36 V Output-Current: 2.5 A Switching-Frequency: 212 kHz to 280 kHz Quote Link to comment Share on other sites More sharing options...
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.