Replacement for LM3915

[Richard Crowley]

I knew it was coming, but was nevertheless shocked when I went to the Texas Instruments website and they didn't acknowledge that the very popular classic National Semi "bar graph driver" series (LM3914, 3915, 3916) had ever even existed. "Page not found" was all they replied with.  What a sad end.   

So I am soliciting help in identifying a microcontroller (or FPGA?) with these characteristics

• One analog input.  8-bit resolution is plenty good enough
• Ten outputs that can drive LED (10-20mA)
• Bonus: very tiny package (BGA?)

The LM391x series had 10 outputs, and there are hundreds of LED bar graph displays which have 10 elements.  That makes them awkward to use with things like LM339 quad comparators (not to mention that this is the 21st century).  I would like to find a single-chip solution. There are many options if I have to devolve by replacing an integrated chip with a bunch of discrete semis and passives.

So, what are my options?  I have some projects (perhaps small-scale commercial products) in mind that could use something like this.  Or are there perhaps (unauthorized) "counterfeit" LM391x chips still available from the Far East?

[BravoV]

  Or are there perhaps (unauthorized) "counterfeit" LM391x chips still available from the Far East?

There are tons of sellers from Aliexpress, friend bought them once while ago and they work as spec.

No particular selection, just randomly search and with high rating from the buyers feedback -> https://goo.gl/dqzq2R or you can search for your self.

[Monkeh]

So.. basically any ADC equipped micro on the market? Most of them can handle sourcing or sinking ~10mA per pin..

[ebclr]

Any processor line that have one AD will fit, foir this and much more than this

PIC16F
C8051F350
MEGA328
STM32F101   
and another thousands models

http://www.ebay.com/itm/LED-Music-Spectrum-Display-Analyzer-MP3-PC-Amplifier-Audio-Level-Indicator-kits-/331734664602?var=&hash=item4d3ced459a:m:mFAX1kyBnHbrqhWlMoYY3fQ

LM3915 still widely available

https://world.taobao.com/search/search.htm?_ksTS=1481264894814_313&spm=a21bp.7806943.20151106.1&_input_charset=utf-8&navigator=all&json=on&q=LM3915&callback=__jsonp_cb&cna=Fb46ECHjIXICAbrne69e0gIM&abtest=_AB-LR517-LR854-LR895-PR517-PR854-PR895

[Kjelt]

Stm8 series, widely used in China for the Led Voltage / Current indicators.
Built in oscillator,  8 or 10 bit adc, cheap.

[Kleinstein]

Many small µC can do the job. For 10 LEDs one will need a µC with something like 14-16 Pins if one does not use a kind of multiplexing. A modern LEDs usually don't need 10 mA any more - one could well use multiplexing to do something like 2 channels from one chip.

With so few pins I would not want BGA, more like tssop, MLF or QFN. The LEDs have certain size anyway. You may not want a tight tolerance process for such a board, maybe even wave soldering.

[forrestc]

I knew it was coming, but was nevertheless shocked when I went to the Texas Instruments website and they didn't acknowledge that the very popular classic National Semi "bar graph driver" series (LM3914, 3915, 3916) had ever even existed. "Page not found" was all they replied with.  What a sad end.   

So I am soliciting help in identifying a microcontroller (or FPGA?) with these characteristics

• One analog input.  8-bit resolution is plenty good enough
• Ten outputs that can drive LED (10-20mA)
• Bonus: very tiny package (BGA?)

The LM391x series had 10 outputs, and there are hundreds of LED bar graph displays which have 10 elements.  That makes them awkward to use with things like LM339 quad comparators (not to mention that this is the 21st century).  I would like to find a single-chip solution. There are many options if I have to devolve by replacing an integrated chip with a bunch of discrete semis and passives.

So, what are my options?  I have some projects (perhaps small-scale commercial products) in mind that could use something like this.  Or are there perhaps (unauthorized) "counterfeit" LM391x chips still available from the Far East?

16F506 in QFN package?  3x3mm.  Under $1.

Actually scratch that... A PIC16F1503 is the same size and the same price, and might open up some interesting applications for you.

[technix]

STC15F401AS in SO-16 or DIP-16? That chip is 20-30 US cents each, 1-cycle 8051 architecture, internal calibrated oscillator and POR, and comes with a 8-bit ADC.

[Monkeh]

LM3915 still widely available

https://world.taobao.com/search/search.htm?_ksTS=1481264894814_313&spm=a21bp.7806943.20151106.1&_input_charset=utf-8&navigator=all&json=on&q=LM3915&callback=__jsonp_cb&cna=Fb46ECHjIXICAbrne69e0gIM&abtest=_AB-LR517-LR854-LR895-PR517-PR854-PR895

Via back alley sellers, yes. The fab which made it is being (has been?) closed.

[Richard Crowley]

Via back alley sellers, yes. The fab which made it is being (has been?) closed.

Has been.  As I mentioned in the original question.
So the only source now is questionable stock from unauthorized, 3rd party sellers.
And of limited and finite supply since they are not being made anymore.
Hence my search for a functional replacement.

[Ian.M]

There are two problems with this idea:
1.  LED current limiting:  Most MCUs will require external resistors for each LED.
2. Supply voltage: A LM3914/5/6 has a max supply voltage of 25V, but most MCUs Vdd <5.5V.

Probably the best solution is to use two chips - a SPI LED driver + a small MCU to do the ADC conversion and control the LED driver.   If the LED driver has a regulated output <5.5V or add an external regulator you've got a lot of options for an 8 pin MCU, but if you choose one that doesn't its far more restrictive.   Microchip's PIC12HV615 has an internal shunt regulator + the required ADC, and is available in a 3x3mm DFN package, and can run from any fixed supply voltage >5V with only an external dropper resistor + a decoupling cap.

[wraper]

I knew it was coming, but was nevertheless shocked when I went to the Texas Instruments website and they didn't acknowledge that the very popular classic National Semi "bar graph driver" series (LM3914, 3915, 3916) had ever even existed. "Page not found" was all they replied with.  What a sad end.   
[/list]

LM3914 is active product. But I won't use it. Except you would need external resistors (I would go for cheap SMD resistor networks), $ 0.5 MCU can do the same or better and will be more flexible and provide additional functionality.

[wraper]

http://eu.mouser.com/ProductDetail/Silicon-Labs/EFM8BB10F2G-A-QFN20/?qs=sGAEpiMZZMu6TJb8E8CjrwBsgQXTdCLERcnzQKHvN68%3d
Extremely small as you asked (3x3 mm), $0.41 @ quantity of 1. 16 I/O (5V tolerant and can drive leds powered from 5V power rail), 12 bit ADC. Precision internal oscillator, don't need any crystal. Max VDD is 3.6V so may be somewhat limiting.
But you can go to a little bit more expensive EFM8UB1 series which have internal 5V->3.3V LDO, and even have USB on top of that, LOL. Could upgrade your bar graph firmware via USB with no other parts that connector needed.
P.S. Check reference manual as datasheet is quiet limited.

[David Hess]

I knew it was coming, but was nevertheless shocked when I went to the Texas Instruments website and they didn't acknowledge that the very popular classic National Semi "bar graph driver" series (LM3914, 3915, 3916) had ever even existed. "Page not found" was all they replied with.  What a sad end.   

TI also ignores older less expensive products which are still active in their selection guides so unless you know exactly what part you are looking for, it often cannot be found.

[MarcusS]

I too have the same problem.  My application that I have has been using LM3915s for an audio power meter display on a production audio amplifier.

I haven't yet found a solution to this.  I'm surprised TI haven't released a replacement for the LM3915 even if the replacement was an SMD package.  Certainly I need to be on a scrounge to build up some stock of these until I have a simple redesign method.  I don't want to go the microcontroller option when it is an IC that is quite simple.  Nor do I want to fill my board up with quad op amps and more discrete resistors when to date I have been able to do what I needed to do with 1 simple IC.

[ElektroQuark]

TI has the LM3914 as an active part in production: CLICK!

[MarcusS]

TI has the LM3914 as an active part in production: CLICK!

I know that.  Not sure how much longer for but besides that its not really suitable for an audio power meter as it is not logarithmic.

[ElektroQuark]

Sorry, the info was for the OP.

EDIT:

Ouch! The original post is from 2016!

[danadak]

Use a PSOC -

For me what stands out is -

1) Routability
2) Fast 12 bit SAR A/D and slow 20 bit DelSig
3) DFB (Digital Filter Block) that is dual channel, handle FIR or IIR filters, or DFB
can be used as a GP fast processor block, similar to RISC block
4) MSI logic elements GUI based and/or the UDB Verilog capability. Eg. the FPGA
like capability
5) Onboard Vref
6) IDAC, VDAC, OpAmps (up to 4), comparator, mixer, switch cap, analog mux....
7) LCD,  COM, UART, I2C, I2S, One Wire, SPI, Parallel, LIN, CAN, BLE, USB
9) Custom components capability, create with schematic capture or Verilog
10) DMA to offload processes like filters, COM, Display
11) ARM M0 (PSOC 4) or M3 (PSOC  5LP) or 8051 core(PSOC 3)
12) Extensive clock generation capabilities
13) All components supported by extensive prewritten APIs

https://www.element14.com/community/thread/23736/l/100-projects-in-100-days?displayFullThread=true

http://www.cypress.com/documentation/code-examples/psoc-345-code-examples

Great video library

Attached component list.  A component is an on chip HW resource.

Free GUI design tool with schematic capture, "Creator". Components have rich API library attached
to each component. Compilers free as well.

PSOC 4 is low end of family, consider 5LP parts as well. PSOC 4 also has arduino footprint boards (pioneer) as well

https://www.elektormagazine.com/labs/robot-build-with-cypress-psoc

http://www.cypress.com/products/32-bit-arm-cortex-m-psoc





Regards, Dana.

[technix]

I am very suspicious of the Cypress PSoC promotional posts here... For tasks like this I would think something like a STM32F030F4P6 is the highest grade processor I would consider using.

[ebclr]

LM3915 still widely available, no needs for replacements

[Richard Crowley]

LM3915 still widely available, no needs for replacements 

It is still on the "Withdrawal of the Select Devices Sourced in GFAB6 " list from Texas Instruments.
Perhaps it is in "zombie" status.  (walking dead).

Furthermore Texas Instruments is selling off the entire Greenock, Scotland site:
http://atreg.com/available-for-sale-ti-200mm-150mm-fab-greenock-scotland/

[Monkeh]

LM3915 still widely available, no needs for replacements

We're all aware your definition of available is a little skewed, but be serious, they're no longer manufacturing the things.

[ebclr]

How many pieces do you want?

Who cares about TI

[Monkeh]

How many pieces do you want?

Who cares about TI

It doesn't matter how many. I want to know they work, haven't been stored in a damp cardboard box for five years, and weren't removed from some old PCB with a blowtorch and the edge of a table.