NTE7125 & NTE7126 Integrated Circuit Switching Regulator Description: The NTE7125 and NTE7126 are integrated circuits in a 12–Lead SIP type package incorporating all the power switching, amplifier, error detection, and overcurrent protection circuits required in a self– extcitation type semi–regulated off–line switching regulator. As a result, these devices can be used in the design of switching power supplies with a minimal number of external components. Furthermore, the adoption of MOSFET power switching elements supports a higher oscillation frequency than possible with bi–polar transistors. This allows smaller pulse transformers and capacitors to be used, making it possible to construct miniature power supply systems. Features: D Power MOSFET Devices D Ideal for Semi–Regulated Control Switching Supplies D Error Detection Circuit On–Chip (40.5V ±0.5V Set Refernce Voltage) D Overcurrent Protection Circuit On–Chip D Higher Oscillation Frequency allows the use of Smaller Pulse Transformers D IMST Substrate acts as an Electromagnetic Shield, makinf Low–Noise Designs Possible Applications: D CRT/CTV Power Supplies D Office Automation Equipment Power Supplies Absolute Maximum Ratings: (TA = +25°C unless otherwise specified) Operating Substrate Temperature (Recommended value is +105°C), TCmax . . . . . . . . . . . . +115°C AC Input Voltage, VAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140Vrms OPerating Temperature Range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –10° to +85°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –30° to +115°C Maximum Output Power (VO = 135V), WOmax NTE7125 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110W NTE7126 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145W TR1 Drain Current, ID NTE7125 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6A NTE7126 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8A Pulse Drain Current, ID (pulse) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20A Drain Reverse Current, IDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6A Gate–Source Voltage, VGSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±30V Absolute Maximum Ratings (Cont’d): (TA = +25°C unless otherwise specified) TR1 (Cont’d) Allowable Power Dissipation, PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78.1W Chip Junction Temperature, TJmax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C Thermal Resistance, Junction–to–Case, RthJ–C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6°C/W ZD1 Allowable Power Dissipation, PZD1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500mW Chip Junction Temperature, TJ (ZD1)max . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +125°C Thermal Resistance, Junction–to–Case, RthJ–C (ZD1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.2°C/W Allowable Operating Ranges: (TA = +25°C unless otherwise specified) Pin4 Input Voltage, V4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±6 to ±24V Oscillator Frequency, fOSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 to 120kHz Operating Characteristics: (TA = +25°C, TC = +25°C unless otherwise specified) Parameter Symbol Test Conditions Output Voltage Setting IIN = 8mA Output Voltage Temperature Coefficient TC = 0° to +105°C, IIN = 8mA Min Typ Max Unit 40.0 40.5 41.0 V – 7 – mV/° C TR1 Drain–Source Breakdown Voltage V(BR)DSS ID = 10mA, VGS = 0V 500 – – V Gate–Source Cutoff Voltage VGS(off) ID = 1mA, VDS = 10V 2.0 – 3.0 V ON Resistance NTE7125 NTE7126 RDS(on) ID = 2.5A, VGS = 10V – – 1.4 0.8 1.8 1.8 Ω Ω – 800 – pF 23.7 – 26.3 V Input Capacitance Ciss VDS = 10V, VGS = 0V, f = 1MHz VZ IZ = 5mA ZD1 Zener Voltage Pin Connection Diagram (Front View) 12 TR1 Drain 11 TR1 Drain 10 9 8 7 6 5 4 3 2 1 No Pin TR1 Source TR1 Source OCP Setting Level Input Amplifier Circuit Control TR1 Gate Drive Voltage Input GND Error Detection Level Vref (40.5V typ) Input 1.835 (46.6) 1.622 (41.2) .335 (8.5) 1.004 (25.5) .500 (12.7) 1 12 .100 (2.54) 1.100 (27.9) .787 (20.0) .261 (6.63) .157 (4.0)