1N5820, 1N5821, 1N5822 10 NOTE 4 - APPROXIMATE THERMAL CIRCUIT MODEL TTS) 7.0 A 5.0 SINE WAVE RqS(A) RqL(A) RqJ(A) RqJ(K) RqL(K) RqS(K) I(FM) TION (W 3.0 p(ResistiveLoad) A I dc TA(A) TA(K) PD 2.0 (AV) TL(A) TC(A) TJ TC(K) TL(K) 1.0 Capacitive SQUARE WAVE 5.010 0.7 Loads 20 0.5 Use of the above model permits junction to lead thermal 0.3 resistance for any mounting configuration to be found. For VERAGE POWER DISSIP 0.2 TJ ≈ 125°C a given total lead length, lowest values occur when one side , A V) of the rectifier is brought as close as possible to the heat sink. 0.1 F(AP 0.1 0.2 0.3 0.5 0.7 1.0 2.0 3.0 5.0 7.0 10 Terms in the model signify: IF(AV), AVERAGE FORWARD CURRENT (AMP) TA = Ambient Temperature TC = Case Temperature Figure 6. Forward Power Dissipation 1N5820-22 TL = Lead Temperature TJ = Junction Temperature RqS = Thermal Resistance, Heatsink to Ambient RqL = Thermal Resistance, Lead-to-Heatsink RqJ = Thermal Resistance, Junction-to-Case PD = Total Power Dissipation = PF + PR PF = Forward Power Dissipation PR = Reverse Power Dissipation (Subscripts (A) and (K) refer to anode and cathode sides, respectively.) Values for thermal resistance components are: RqL = 42°C/W/in typically and 48°C/W/in maximum RqJ = 10°C/W typically and 16°C/W maximum The maximum lead temperature may be found as follows: TL = TJ(max) n TJL where n TJL RqJL · PD Mounting Method 1Mounting Method 3 P.C. Board where available P.C. Board with NOTE 5 — MOUNTING DATA copper surface is small. 2-1/2, x 2-1/2, copper surface. Data shown for thermal resistance junction-to-ambient (Rq L L JA) for the mountings shown is to be used as typical guideline values É L = 1/2″ for preliminary engineering, or in case the tie point temperature ÉÉÉÉÉÉÉ É cannot be measured. TYPICAL VALUES FORR ÉÉÉÉÉÉÉ É q JA IN STILL AIRLead Length, L (in)Mounting Method 2 É MountingMethod É BOARD GROUND 1/81/41/23/4R q L L JA PLANE 1 50 51 53 55 °C/W ÉÉÉÉÉÉÉÉ 2 58 59 61 63 °C/W ÉÉÉÉÉÉÉÉ VECTOR PUSH-IN 3 28 °C/W TERMINALS T-28 http://onsemi.com6