Introduced in 1972 by Signetics, the 555 is still in widespread use due to its low price, ease of use, and stability. It is now made by many companies in the original bipolar and in lowpower CMOS technologies. As of 2003, it was estimated that 1 billion units were manufactured every year. The 555 is the most popular integrated circuit ever manufactured.

The seven band graphic equalizer IC is a CMOS chip that divides the audio spectrum into seven bands. 63Hz, 160Hz, 400Hz, 1kHz, 2.5kHz, 6.25kHz and 16kHz. The seven frequencies are peak detected and multiplexed to the output to provide a DC representation of the amplitude of each band. No external components are needed to select the filter responses. Only an off chip resistor and capacitor are needed to select the on chip clock oscillator frequency. The filter center frequencies track this frequency.

Other than coupling and decoupling capacitors, no other external components are needed. The chip supply can be between 2.7 and 5.5 volts with 5 volts providing the best performance. The device has very low quiescent current (less than 1ma typical) for portable audio devices. the multiplexer is controlled by a reset and a strobe, permitting multiplexer readout with only two pins. The multiplexer readout rate also controls the decay time (10% decay per read), so no external pins are needed for this function.

The LM1875 is a monolithic power amplifier offering very low distortion and high quality performance for consumer audio applications.

The LM1875 delivers 20 watts into a 4Ω: or 8Ω load on ±25V supplies. Using an 8Ω load and ±30V supplies, over 30 watts of power may be delivered. The amplifier is designed to operate with a minimum of external components. Device overload protection consists of both internal current limit and thermal shutdown.

The LM3886 is a high-performance audio power amplifier capable of delivering 68W of continous aerage power to a 4Ω load and 38W into 8Ω with 01% THD+N from 20hZ to 20kHz.

Can be run in dual or single voltage supply mode. This is V+, V- & GND or just V+ and GND. Supply can be from 20VDC to 94VDC.

The TDA7293 is a monolithic integrated circuit in Multiwatt15 package, intended for use as audio class AB amplifier in Hi-Fi field applications, such as home stereo, self powered loudspeakers and Topclass TV. Thanks to the wide voltage range and to the high ou tput current capab ility it is able to supply the highest power into both 4- Ω and 8- Ω loads.

The built-in muting function with turn-on delay simplifies the remote operation avoiding on-off switching noises.

Parallel mode is possible by connecting several devices and using pin11. High output power can be delivered to very low impedance loads, so optimizing the thermal dissipation of the system

The LM3914 is an integrated circuit designed by National Semiconductor and used to operate displays that visually show the magnitude of an analog signal. One LM3914 can drive up to 10 LEDs, LCDs, or vacuum fluorescent displays on its outputs.

The LM3916 is a monolithic integrated circuit that senses analog voltage levels and drives ten LEDs, LCDs or vacuum fluorescent displays, providing an electronic version of the popular VU meter. One pin changes the display from a bar graph to a moving dot display. LED current drive is regulated and programmable, eliminating the need for current limiting resistors. The whole display system can operate from a single supply as low as 3V or as high as 25V.

The LM3916 is similar to the LM3914 except the 3914 is designed for voltages where the 3916 is more for audio. Either can be bar or dot.

The AN6884 is a monolithic integrated circuit driving 5-LED and is capable of logarithmic (dB) bar graph display for input signal. Incorporating high gain rectification amp enable to apply AC (UV meter, etc.) / DC (signal meter, etc) level meter widely.

Wide range of operating voltages: 3.5 to 16V
Constant current output
Built in high gain amp
Low noise when LED on
5-dot LED bar logarithmic response: -10, -5, 0, 3, 6db
Few External Components required

The KA2284 is a monolithic integrated circuit designed for 5-dot LED level meter drivers with a built-in rectifying amplifier. It is suitable for AC/DC level meters such as VU meters or signal meters

High gain rectifying amplifier included(Gv=26dB)
Low radiation noise when LED turns on
logarithmic indicator for 5-dot LED of bar type.
Constant current output( 15mA)
Wide operating supply voltage(3.5V~16V)
Not necessary diode or transistor for ALC
Minimum number of external parts required

The CD4017BC is a 5-stage divide-by-10 Johnson counter with 10 decoded outputs and a carry out bit.

• High speed 16 pin CMOS Decade counter
• Supports 10 decoded outputs
• Wide supply voltage range from 3V to 15V, typically +5V
• TTL compatible
• Maximum Clock Frequency: 5.5Mhz

The IC CD4017 is used for counting applications, it has the capability to turn on 10 outputs sequentially in a pre-defined time and reset the count or hold it when required. It also has the capability to indicate the status of counting using Carry pin. This is commonly used for Led chasers and other logical output projects, so if you are looking for an sequential decoded counting IC that can count up to 10 then this IC will be your right choice

The seven band graphic equalizer IC is a CMOS chip that divides the audio spectrum into seven bands. 63Hz, 160Hz, 400Hz, 1kHz, 2.5kHz, 6.25kHz and 16kHz. The seven frequencies are peak detected and multiplexed to the output to provide a DC representation of the amplitude of each band. No external components are needed to select the filter responses. Only an off chip resistor and capacitor are needed to select the on chip clock oscillator frequency. The filter center frequencies track this frequency.

Other than coupling and decoupling capacitors, no other external components are needed. The chip supply can be between 2.7 and 5.5 volts with 5 volts providing the best performance. The device has very low quiescent current (less than 1ma typical) for portable audio devices. the multiplexer is controlled by a reset and a strobe, permitting multiplexer readout with only two pins. The multiplexer readout rate also controls the decay time (10% decay per read), so no external pins are needed for this function.

• Low Power Consumption
• Only Two External Components
• On Chip Ground Reference
• Switched - Capacitor Filters
• 3.3 or 5 Volts Operation
• 20 dB of Gain
• On Chip Oscillator
• Output Multiplexer
• Variable Decay Time
• 8 Pin DIP Package

Add another 16 pins to your microcontroller using a MCP23017 port expander. The MCP23017 uses two i2c pins (these can be shared with other i2c devices), and in exchange gives you 16 general purpose pins. You can set each of 16 pins to be input, output, or input with a pullup. There's even the ability to get an interrupt via an external pin when any of the inputs change so you don't have to keep polling the chip.

Use this chip from 2.7-5.5V (good for any 3.3V or 5V setup), and you can sink/source up to 20mA from any of the I/O pins so this will work for LEDs and such. Team it up with a high-power MOSFET if you need more juice. DIP package means it will plug into any breadboard or perfboard.

You can set the i2c address by tying the ADDR0-2 pins to power or ground, for up to 8 unique addresses. That means 8 chips can share a single i2c bus - that's 128 I/O pins!

Two Channel Audio amplifier. 6W per channel

• Output Voltage: 9.5 to 18V
• Fixed Gain: 20dB

Purchased 20 pcs

Interface: SPI
Test Temperature Range: 0° F ~ 1875.5° F
Accuracy: +/- 0.45° F
Operating Voltage Range: 3.0 ~ 5.5V
Operating Current: 50mA
Operating Temperature Range: -4° F ~ 185° F
Module Size: 15mm * 28mm, with a 3mm diameter screw holes
K type thermocouple junction location, use 301 ordinary terminals
Application: Industrial, Appliances, HVAC