NTE1850 Integrated Circuit Dual 12W/Channel Audio Power Amplifier Description: The NTE1850 is a dual Hi–Fi audio power amplifier in a 9–Lead SIP type package designed for mains–fed applications such as stereo TV sound and stereo radio. The circuit is optimal for symmetrical power supplies but is also well suited to asymmetrical power supply systems. An output power of 2 x 12W (THD = 0.5%) can be delivered into an 8Ω load with a symmetrical power supply of ±16V. The gain is fixed internally at 30dB, but can be changed externally if required. Internal gain fixing gives low gain spread and very good balance between the amplifiers (0.2dB). A special feature is an input mute circuit which provides suppression of unwanted signals at the inputs during switching on and off. This circuit disconnects the non–inverting inputs when the supply voltage is below ±6V, while allowing the amplifiers to remain in their DC operating condition. Two thermal protection circuits are provided, one monitors the average junction temperature and the other the instantaneous temperature of the power transistors. Both protection circuits activate at +150°C, allowing safe operation to a maximum junction temperature of +150°C without added distortion. Applications: Features: D Few External Components Required D Stereo D Input Muted During Power ON/OFF D TV Sound D Low Offset Voltage Between Output and GND D Radio D Excellent Gain Balance Between Channels D Short–Circuit Protected D Thermally Protected Absolute Maximum Ratings: Supply Voltage (Pin5 and Pin7), VCC = V5, 7–3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +20V Non–Repetitive Peak Output Current (Pin4 and Pin6), IOSM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4A Total Power Dissipation (TA = +25°C, Infinite Heatsink), PTOT . . . . . . . . . . . . . . . . . . . . . . . . . . . 15W Derate Above 25°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5°C/W Operating Junction Temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C Short–Circuit Time (Outputs Short–Circuited to GND), tSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Hr Thermal Resistance, Junction–to–Case, RthJC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25°C/W DC Electrical Characteristics: Parameter Symbol Test Conditions Min Typ Max Unit Supply Voltage Range VCC – ±16 ±20 V Repetitive Peak Output Current IORM – – 2.2 A ±7.5 ±16 ±20 V Operating Mode (Symmetrical Power Supply, VCC = ±16V, RL = 8Ω, TA = +25°C, f = 1kHz) Supply Voltage Range VCC Total Quiescent Current ITOT Without RL – 50 – mA Output Power PO THD = 0.5% 10 12 – W THD = 10% 10 15 – W PO = 6W – – 0.2 % THD = 0.5%, Note 1 20Hz to 20kHz Total Harmonic Distortion Power Bandwidth Voltage Gain Noise Output Voltage THD B GV 30 31 dB – 70 140 µV 14 20 26 kΩ Note 2 40 60 – dB RS = 0Ω 46 70 – dB – 0.3 – µA – 20 200 mV ±2 – ±5.8 V VNO(RMS) RS = 2kΩ, unweighted (20Hz to 2okHz) Input Impedance |Zi| Ripple Rejection RR Channel Separation ∞ Input Bias Current IIB DC Output Offset Voltage 29 VOFF WRT GND Input Mute Mode (Symmetrical Power Supply, VCC = ±4V, RL = 8Ω, TA = +25°C, f = 1kHz) Supply Voltage VCC Total Quiescent Current ITOT Without RL – 30 – mA Output Voltage VOUT VI = 600mV – – 1.8 mV – 70 140 µV Note 2 35 – – dB WRT GND – 20 200 mV Noise Output Voltage Ripple Rejection DC Output Offset Voltage VNO(RMS) RS = 2kΩ, unweighted (20Hz to 2okHz) RR VOFF Operating Mode (Asymmetrical Power Supply, VCC = ±4V, RL = 8Ω, TA = +25°C, f = 1kHz) Total Quiescent Current ITOT Without RL – 50 – mA Output Power PO THD = 0.5% 5 6 – W THD = 10% 5 8.5 – W PO = 4W – – 0.2 % THD = 0.5%, Note 1 40Hz to 20kHz Total Harmonic Distortion Power Bandwidth THD B Voltage Gain GV 29 30 31 dB Gain Balance ∆GV – 0.2 – dB – 70 140 µV 14 20 26 kΩ Note 2 40 50 – dB RS = 0Ω 40 – – dB Noise Output Voltage VNO(RMS) RS = 2kΩ, unweighted (20Hz to 2okHz) Input Impedance |Zi| Ripple Rejection RR Channel Separation ∞ Note 1. Power Bandwidth at PO(MAX) = –3dB. Note 2. Ripple Rejection at RS = 0Ω, f = 100Hz to 20kHz; ripple voltage = 200mV (RMS value) applied to positive or negative supply rail. Pin Connection Diagram (Front View) 1 Non–Inverting Input 1 2 Inverting Input 1 3 GND 4 Output 1 5 –VCC 6 Output 2 7 +VCC 8 Inverting Input 2 9 Non–Inverting Input 2 .961 (24.4) .780 (19.8) .185 (4.7) .489 (12.4) 9 1 .079 (2.0) .674 (17.0) .079 (2.0) .100 (2.54)