Darlington transistors with built-in temperature compensation diodes for audio amplifier applications SAPseries Features ●Built-in temperature compensation diodes and one emitter resistor ●Real time temperature compensation The temperature compensation diodes are mounted on one chip and placed in the center of the chip to detect temperature rises directly. ●Elimination of the temperature dependency of the idling current The temperature coefficient of the diodes is optimized to have the idling current stabilized; thus one of the fatal failure modes in conventional Darlington transistors, Thermal Runaway, is avoidable. ●Symmetrical design for the PNP and the NPN pinouts The new design minimizes the length of the pattern layout, and output distortions are controlled. ●Darlington transistors, temperature compensation diodes and one emitter resistor are incorporated in one package, so labor for parts insertion as well as the parts count is reduced. Line up Part Number PC (W) VCEO (V ) IC (A) hFE Emitter resistor (Ω) SAP15P/SAP15N 150 160 15 5000 to 20000 0.22 SAP10P/SAP10N 100 150 12 5000 to 20000 0.22 SAP08P/SAP08N 80 150 10 5000 to 20000 0.22 ■External Dimentions (Unit : mm) 3.2±0.2 4.5±0.2 1.6±0.2 5±0.2 3.3±0.2 15.4±0.3 9.9±0.2 ■Equivalent Circuit Diagram NPN PNP C E D 3.4max a b (2.5) +0.2 0.65 –0.1 S S D 1±0.1 B R: 70Ω Typ. Emitter resistor RE: 0.22Ω Typ. E C BD C S E E S C D B (18) +0.2 1.35 –0.1 Emitter resistor RE: 0.22Ω Typ. R :70Ω Typ. 2±0.1 (36°) (41) 7±0.2 22±0.3 23±0.3 28±0.3 B +0.2 0.8 –0.1 2.54±0.1 3.81±0.1 2.54±0.1 (7.62) +0.2 0.65 –0.1 3.81±0.1 (12.7) 17.8±0.3 4±0.1 ➀➁ ➂ ➃➄ Weight: approx 8.3g a. Part Number b. Lot Number Application Information 1. Recommended Operating Conditions ➀Add a variable resistor (VR) between diode terminals to adjust the idling current. The resistor having 0 to 200Ω is to be used. ➁Adjust the forward current flowing over the diodes at 2.5mA. ➂Adjust the idling current at 40mA with the external variable resistor. Both the temperature coefficients for the transistor and the diodes are matched under the above conditions. Both the PNP and the NPN are Darlington transistors, so the temperature change ratio of the total four VBE of the transistors is subject to the compensation. One PN junction diode in the NPN and five Schottky barrier diodes in the PNP are built-in, and the total six diodes are operating as the temperature compensation. The temperature coefficient of the total diodes (its variable value) becomes smaller with a larger forward current (approximately – 0.2mV/°C to 1mA), and the coefficient of the total transistors (its variable value) also becomes smaller with a larger idling current (approximately – 0.1mV/°C to 10mA), but the both variable values are small. Thus, the distortion of the temperature coefficient caused by the different current is small, so the thermal runaway may not be occurred due to the changes of the recommended ratings; however, the actual operation is to be confirmed by using an experimental equipment or board. +VCC NPN C B S D 2.5mA E 40mA E D External variable resistor (VR) (0 to 200Ω) S B PNP C –VCC 2. External Variable Resistor Total forward voltage (at IF =2.5mA) of the diodes is designed to be equal or less than that of total VBE (at IC = 40mA) of the transistor, thus the idling current is required to be adjusted at 40mA with an additional external variable resistor. The relations are shown as below: Total VF of Diode ∆V=0 to 500mV Total VBE of Transistor + Total VRE of Emitter Resistor The VBE of the transistor is dependent to the hFE, and the VBE is lower with higher hFE and vice versa. The hFE for both the PNP and the NPN varies between 5k and 20k; thus the VBE is the lowest with the combination of maximum hFE (20k) each and it is the highest with the combination of minimum hFE (5k) each. Presuming the voltage difference between the VF of the diodes and the VBE of the transistors (including the total voltage drops of the two emitter resistors) as ∆V. Minimum VBE – Maximum VF variations of the diodes = 0 Maximum VBE – Minimum VF variations of the diodes = 500mV The current flowing over the diodes and the VR is adjusted at 2.5mA; therefore 500mV 2.5mA = 200Ω Consequently, the applicable VR value is to be 0 to 200Ω VBE Min. (P and N: hFE Max.) VBE Max. (P and N: hFE Min.) IC 40mA Di VF Variations VBE TR VBE Variations ∆VF =500mV 3. Characteristics of the temperature compensation diodes The several temperature compensation diodes are connected in series, so the forward voltage is varied with small current fluctuations. Therefore, in case the forward current flowing over the diodes is set at 2.5mA and over, the forward voltage rises, and in the worst combinations, the idling current reaches to 40mA and over with minimum VR of 0Ω. On the contrary, in case the forward current is set at 2.5mA or below, the idling current may not reach to 40mA with maximum VR of 200Ω. 10.0 Ta=25°C PN-Di SBD (5 diodes Total) PN–Di+SBD IF (mA) 5.0 1.0 0 500 1000 1500 2000 2500 3000 VF (mV) IF – VF Characteristics 4. Parallel push-pull application Adjustments of the idling current are required by each the resistor in parallel push-pull applications. One side adjustment will cause the idling current to be unstable (seesaw operation) because of the different hFE. To be adjusted individually 5. Destruction capacity of the built-in emitter resistor The built-in resistor is fabricated with polysilicone on the chip for the SAP08P/N and a thick-film resistor is used for the SAP10P/N and SAP15P/N. The latter, the thick-film resistor, has weaker destruction point in the Pc area (especially for large current flowing area) rather than that of the transistor chip itself. This is subject to the area beyond Safe Operating Area (S.O.A). However, under the evaluation like a short circuit test in which the current exceeds the guaranteed value, it may cause the emitter resistor to be destroyed before the transistor itself is destroyed. Consequently, the current value (or time) that operates the protection circuit is to be set at lower than that of discrete device configurations. In the application of car audio amplifiers, the same manners as the above need to be considered because the large current is flowed at low impedance. In addition, once the transistor falls into thermal runaway due to a soldering failure to the external VR added between diodes or other failure manners, as the worst case, there may cause a resin crack or smoke emissions by flare up. Flame retardant molding resin is used, and the material of the product is conformed to the most sever standard UL94V0. However it is recommended that the careful consideration be given to a protection circuit, and the protection circuits should be provided appropriately in due course. If the operating conditions are not to be matched to the ratings, it is also recommended that the E (Emitter resistor) terminal should be opened and the external emitter resistor should be added to the S (Sensing) terminal shown as below. (However this is not applicable to the SAP08P/N because a thin inner lead is used for S terminal.) IC Transistor destruction point C Thick-film resistor destruction point B A.S.O. Curve S D External emitter resistor E Output terminal VCE Built-in temperature compensation diodes Built-in emitter resistor Darlington Equivalent circuit SAP08N B D Application: Audio V IC 10 A IB 1 A PC 80 ( Tc = 25°C) W 10 mA 150 °C –55 to +150 °C Di IF Tj Tstg typ Unit max 100 µA 100 µA IEBO VEB =5V VCEO IC =30mA 150 hFE ✽ VCE =4V, IC =6A 5000 VCE(sat) IC =6A, IB =6mA 2.0 V VBE(sat) IC =6A, IB =6mA 2.5 V (36°) V 20000 a b VBE VCE =20V, IC =40mA 1220 mV IF =2.5mA 705 mV Di VF IE =1A RE 0.176 0.22 IC – VCE Characteristics (Typical) 2.54±0.1 (12.7) 1.0m A 1.8mA 0.8m Collector Current IC (A) 0.5mA 6 0.3mA 4 IB = 0.2mA 2 0 4 2 2 IC =8A 6A 4A 1 0 0.3 0.5 1 j-a (°C/W) Transient Thermal Resistance 25°C –30°C 1000 500 200 0.03 0.1 0.5 1 10 50 100 5 3 1 0.5 0.1 1 10 5 10 50 100 500 1000 2000 Time t (ms) Safe Operating Area (Single Pulse) PC – Ta Derating 30 10 m 0m s s 10 5 D. C fin ite he 40 sin at k Without Heatsink Natural Cooling In 0.5 ith 1 60 W Maximum Power Dissipation Pc (W) 80 10 20 0.1 0.05 3 5 10 50 100 Collector-Emitter Voltage VCE (V) 200 3.5 0 4 125°C 25°C Without Heatsink 0 25 50 75 100 0 – 30°C 0 1 2 Base-Emitter Voltage VBE (V) Characteristics Collector Current IC (A) Collector Current IC (A) DC Current Gain hFE j-a – t 125°C 5000 5 Base Current IB (mA) hFE – IC Characteristics (Typical) 10000 6 2 6 50000 (VCE =4V) 8 Collector-Emitter Voltage VCE (V) (VCE = 4V) S E 10 Collector Current IC (A) A 1.3mA C Weight: Approx 8.3g a. Part Number b. Lot Number IC – VBE Temperature Characteristics 3 Collector-Emitter Saturation Voltage VCE(sat) (V) mA 1.5 +0.2 0.65 –0.1 3.81±0.1 (7.62) 17.8±0.3 4±0.1 VCE(sat) – IB Characteristics (Typical) 8 0 1±0.1 +0.2 0.8 –0.1 2.54±0.1 3.81±0.1 Ω 0.264 +0.2 0.65 –0.1 B D 10mA 2.5mA 2.0mA 4.5±0.2 1.6±0.2 +0.2 1.35 –0.1 ✽Rank O (5000 to 12000), Y (8000 to 20000) 10 3.2±0.2 15.4±0.3 9.9±0.2 2±0.1 V 5 min VCB =150V (41) 150 VEBO Conditions ICBO 5±0.2 VCEO Symbol (Unit: mm) (18) V External Dimensions 7±0.2 22±0.3 0.3 ± 23 28±0.3 150 ( Ta = 25°C) Ratings 3.3±0.2 VCBO ■Electrical Characteristics (2.5) Unit 3.4max ■Absolute maximum ratings (Ta=25°C) Ratings S Emitter resistor RE: 0.22Ω Typ. R: 70Ω Typ. E (Complement to type SAP08P) Symbol C 125 Ambient Temperature Ta (°C) 150 3