diff --git a/libraries/io/fpga_temp_sens/src/vhdl/fpga_temp_sens.vhd b/libraries/io/fpga_temp_sens/src/vhdl/fpga_temp_sens.vhd
index 727e24c05c3086c91471108735e1cc74e2d0913e..a9e9142f029ab2dc894d2bd5d1dd20bf4803202b 100644
--- a/libraries/io/fpga_temp_sens/src/vhdl/fpga_temp_sens.vhd
+++ b/libraries/io/fpga_temp_sens/src/vhdl/fpga_temp_sens.vhd
@@ -91,7 +91,8 @@ BEGIN
 
 
   gen_no_tech_fpga_temp_sens: IF g_sim=TRUE GENERATE
-    temp_data <= RESIZE_UVEC(x"45",10);
+    -- temp = (708 * adc)/1024 - 273 => adc = (temp + 273)*1024/708
+    temp_data <= TO_UVEC(460, temp_data'LENGTH);   -- choose temp = 45 degrees so adc temp_data = 460
     mm_reg_temp_data <= RESIZE_UVEC(temp_data,c_mem_reg_dat_w);
   END GENERATE;