Simple stereo headphone amplifier for audio DACs required a differential signal. The circuit works with dual +/-5V DC supply, the project can drive load 16 Ohms to 600 Ohms. Headphone amplifier provides output 50mW into 32 Ohms. Signal for the right channel and left channel input is applied to the amplifier through connectors CN1and CN3, respectively. The source such as an audio analyzer or audio digital-to-analog converts (DAC). The positive input from the source connects to the pin labeled I1+/I2+, the negative input from the source connects to the pin labeled I1-/I2-, and the ground connection from the source connects to the center pin of CN1 and CN3, labeled GND. Output connections are provided through the use of the CN2, CN4 provided to power up the board, D1 power LED. OPA1688 or OPA1622 op-amps are good for the applications.
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- Supply Input +/-5V DC
- Load 16 Ohms to 600 Ohms (32 Ohms Ideal)
- Output Load 50mW into 32 Ohms Headphone
- Frequency Response 20 Hz to 20 kHz
Power operational board can drive high current load up to 3Amps, the board helpful to drive Dc Motor, solenoid, Lamp, LED and industrial application. The project built around LM675 power op-amp from texas instruments. All resistors are 1%. Refer datasheet of LM675 for further information.
I Output= VIN X 2.5amps/volt
i.e Iout=1A when VIN=400mV
Trimmer Pot for Max Rout
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The LM675 is a monolithic power operational amplifier featuring wide bandwidth and low input offset voltage, making it equally suitable for AC and DC applications.
The LM675 is capable of delivering output currents in excess of 3 amps, operating at supply voltages of up to 48V. The device overload protection consists of both internal current limiting and thermal shutdown. The amplifier is also internally compensated for gains of 10 or greater.
- 3A Current Capability
- AVO Typically 90 dB
- 5 MHz Gain Bandwidth Product
- 8 V/μs Slew Rate
- Wide Power Bandwidth 70 kHz
- 1 mV Typical Offset Voltage
- Short Circuit Protection
- Thermal Protection with Parole Circuit (100% Tested)
- 16V–48V Supply Range ( +/-12 To 24V DC)
- Wide Common-Mode Range
- Internal Output Protection Diodes
- 90 dB Ripple Rejection
Original Circuit from Texas Instruments Data Sheet
The high sensitive analog light sensor module can be used in light detection application, to make LUX meter. The sensor provides voltage output proportional to light falls on the sensor.
Single Supply: 2.7 to 36 V
Photodiode Size: 0.090 inch × 0.090 inch (2.29 mm × 2.29 mm)
Internal 1-MΩ Feedback Resistor
High Responsivity: 0.45 A/W (650 nm)
Bandwidth: 14 kHz at RF = 1 MΩ
The OPT101 is a monolithic photodiode with an on-chip trans-impedance amplifier. The integrated combination of the photodiode and trans-impedance amplifier on a single chip eliminates the problems commonly encountered in discrete designs, such as leakage current errors, noise pick-up, and gain peaking as a result of stray capacitance. Output voltage increases linearly with light intensity. The amplifier is designed for single or dual power-supply operation.
Professional stereo audio line receiver is based on INA1650 device is designed to require a minimum number of external components to achieve data sheet level performance in audio line-receiver applications. Circuit shows the INA1650 used as a differential audio line receiver in split-supply systems that are common in professional audio applications. The line receiver recovers a differential audio signal which may have been affected by significant common-mode noise. The INA1650 is a high common-mode rejection audio line receiver from the Sound Plus line of audio Amplifier products from Texas Instruments.
- Supply +/- 15V DC
- Common-Mode Rejection Ratio (CMRR) VIN = 1 Vrms at 1 kHz –90 dB
- THD+N at 1 kHz VIN = +22 dBu –120 dB
- Second Harmonic – VOUT = 10 Vrms, F = 1 kHz –134.35 dBc
- C1,C2 10uF/25V SMD 1210
- C3, C7, C10, C12 10uF/35V Non Polar
- All Resistors SMD 0805 5%
- C6,C11 10uF/35V SMD 1206
- C2, C5, C8, C9, SMD 0805
- LED SMD 0805
The dual-channel INA1650 and single-channel INA1651 (INA165x) SoundPlus™ audio line receivers achieve an extremely-high common-mode rejection ratio (CMRR) of 91 dB while maintaining an ultra-low THD+N of –120 dB at 1 kHz for 22-dBu signal levels. Precision matching of on-chip resistors gives the INA165x devices excellent CMRR performance. These resistors have matching that is far superior compared to external components and are immune to mismatches introduced by printed circuit board (PCB) layout. Unlike other line receiver products, the INA165x CMRR is characterized over temperature and tested in production to deliver consistent performance in a wide variety of applications.
The INA165x devices operate over a very-wide-supply range of ±2.25 V to ±18 V, on 10.5 mA of supply current. In addition to the line-receiver channels, a buffered mid-supply reference output is included, making the INA165x configurable for dual- or single-supply applications. The mid-supply output can be used as a bias voltage for other analog circuitry in the signal chain. These devices are specified from –40°C to +125°C.
- High Common-Mode Rejection:
- 91 dB (Typical)
- High Input Impedance: 1-MΩ Differential
- Ultra-Low Noise: –104.7 dBu, Unweighted
- Ultra-Low Total Harmonic Distortion + Noise:
- –120 dB THD+N (22 dBu, 22-kHz Bandwidth)
- Wide Bandwidth: 2.7 MHz
- Low Quiescent Current: 6 mA (INA1651, Typical)
- Short-Circuit Protection
- Integrated EMI Filters
- Wide Supply Range: ±2.25 V to ±18 V
High efficient and compact project is capable of driving a 3Amp load with excellent line and load regulation with output adjustable 1.2V to 35V DC. The project built around LM2596ADJ regulator which is ideally suited for easy and convenient design of step-down switching regulator using buck converter topology. Adjustable output version of LM2596 is internally compensated to minimize the number of external components to simplify the power supply design. PCB dimensions 39.65 X 33.20MM
- Adjustable Output Voltage Range 1.23 V 35 V
- Guaranteed 3.0 A Output Load Current
- Wide Input Voltage Range up to 40 V
- 150 kHz Fixed Frequency Internal Oscillator
- Thermal Shutdown and Current Limit Protection
- Internal Loop Compensation
- Moisture Sensitivity Level (MSL) Equals 1
- Simple HighEfficiency StepDown (Buck) Regulator
- Efficient regulator for Linear Regulators
- OnCard Switching Regulators
- Positive to Negative Converter (buck-boost)
- Negative StepUp Converters
- Power Supply for Battery Chargers
Bill Of Material
R1 4K7 SMD 0805
R2 1.21K 1% SMD 0804
PR1 TRIMMER POTENTIOMETER
L1 33uH/5A SMD 12MM INDUCTOR
C2,C3 220uF/50V SMD ELECTROLYTIC
C1 100uF/50V SMD ELECTROLYTIC
LM2596-ADJ TO263 SMD ONSEMI/TEXAS INSTRUMENTS
D1 MBRS340T3 SMD ON SEMI
D2 RED LED SMD 0805
CN1, CN2 2 PIN SCREW TERMINALS
This Simple Photo Diode Amplifier project is based on OPA381 Trans-impedance amplifiers. The circuit Convert Current Output of Photodiodes to Voltage. The circuit ideally suited for low noise amplification of very small photodiode current. The circuit required 5V DC and provides approx. 0.5V to 4V DC.
- Supply 5V DC
- Output 0.5V to 4V Approx.
- Convert Current Output of Photodiodes to Voltage
The OPA381 family of Trans-impedance amplifiers provides 18MHz of Gain Bandwidth (GBW), with extremely high precision, excellent long-term stability, and very low 1/f noise. The OPA381 features an offset voltage of 25μV (max), offset drift of 0.1μV/°C (max), and bias current of 3pA. The OPA381 far exceeds the offset, drift, and noise performance that conventional JFET op amps provide. The signal bandwidth of a trans-impedance amplifier depends largely on the GBW of the amplifier and the parasitic capacitance of the photodiode, as well as the feedback
resistor. The 18MHz GBW of the OPA381 enables a trans-impedance bandwidth of > 250kHz in most configurations. The OPA381 is ideally suited for fast control loops for power level measurement on an optical fiber. As a result of the high precision and low-noise characteristics of the OPA381, a dynamic range of 5 decades can be achieved. This capability allows the measurement of signal currents on the order of 10nA, and up to 1mA in a single I/V conversion stage. In contrast to logarithmic amplifiers, the OPA381 provides very wide bandwidth throughout the full dynamic range. By using an external pull-down resistor to –5V, the output voltage range can be extended to include 0V.