Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Why there is components like capacitor, resistor.. outside the ic?

Status
Not open for further replies.

Vraj

Advanced Member level 4
Joined
Jul 15, 2016
Messages
119
Helped
2
Reputation
4
Reaction score
2
Trophy points
18
Activity points
1,038
Hi,

Can big value components like cpas, resistor, inductor.. stored inside the ic?

Why they are connected outside the ic and increase the pcb size!

Is it possible with big values like 1 uf?

Thanks
 

A 1uF capacitor or higher values and a fairly low value inductor or higher values are larger than the IC chip.
If you want a small pcb size then select a circuit that does not use high value outside parts.

A simple circuit can use a 1uF capacitor and a 1M resistor to make a time delay of 1 second. Or a 0.001uF capacitor, a 1M resistor and a frequency divider that divides by 1000. Or a 10pF tiny capacitor, a 100k resistor and a frequency divider that divides by 1,000,000.

The ICs that flash my cheap solar garden lights have the timing capacitor and resistor inside They probably also have frequency dividers. They have the small inductor that boosts the voltage outside the IC.
Some of my cheap solar garden lights have LEDs with 3 colors and an IC inside the LED that has capacitors and resistor timers inside that flash and fade the colors. Their circuit is designed to use very low value capacitors and resistors that fit inside the LED IC.
 
  • Like
Reactions: Vraj

    Vraj

    Points: 2
    Helpful Answer Positive Rating
Can big value components like cpas, resistor, inductor.. stored inside the ic?

It would even be possible, easily at least with capacitors and resistors, but the cost of doing this in silicon would be so prohibitive that no one would buy such an integrated circuit. In fact, even the resistors that are modeled in the internal diagrams of IC's are not synthesized only with resistive components, but with transistors in the form of current sources that actually performs the same function as a resistor would do. Anyway, for circuits operating at slightly lower frequencies, such as in the audio for example, it is possible to digitize the signal and to do computationally the process that would previously be done analogously.
 
  • Like
Reactions: Vraj

    Vraj

    Points: 2
    Helpful Answer Positive Rating
Hi,

Look for information about IC construction. Basically, from what I understand, ICs are a lot of transistors (mosfets can be used as resistors or capacitors). The passive components are among the most expensive parts to make: the resistors can have a tolerance of 20% - so factor in the additional cost of zapping and trimming for more precise ICs; the capacitors can't be made that big, as already mentioned, they're in the low pF range if onboard; I believe there are ICs that contain inductors, I guess they will be tiny values. A 1uF polyester/PPS capacitor is almost like a sugar cube, it won't fit inside any IC. A tiny (0405?) 1uF ceramic capacitor is almost as big as some of the newer design ICs. There's no point in a $10 IC that could cost $0.5 just to force in components the user can supply.
 
  • Like
Reactions: Vraj

    Vraj

    Points: 2
    Helpful Answer Positive Rating
Hi,

Hmm, so I will need to use capacitor as power supply filter outside the ic.

What will the projected cost of ic with 8051 architecture, ADC, DAC, power management, watchdog, 150kb ram, Bluetooth transceiver,and some little peripherals?

Thanks
 

Few people on this forum design and make ICs. Instead we simply buy them because they are available and are very inexpensive.
 

Hi,

Hmm, so I will need to use capacitor as power supply filter outside the ic.

What will the projected cost of ic with 8051 architecture, ADC, DAC, power management, watchdog, 150kb ram, Bluetooth transceiver,and some little peripherals?

Thanks

Anywhere between 1K USD and 1M USD. Your specs are very vague. Don't go anywhere near ASICs if you think PCB size is a big issue...
 
  • Like
Reactions: Vraj

    Vraj

    Points: 2
    Helpful Answer Positive Rating
Hi,
Hmm, Can you connect with that person?
Few people on this forum design and make ICs.
Let's say, I need high quantity, what will be the price? Will it >1 or<1 dollar?
Ic like csr8645.

Thanks
 

You will have to do your own shopping. Most sites like digikey will give you a price list dependent on how many you want.
 

Hi,
Ic like csr8645.
I ment ASIC that has many same future as CSR8654.
Anywhere between 1K USD and 1M USD.
for how many quantity?

Arm processor has pre designed ICS that I need so I am asking this questions like price.

Thanks
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top