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AnsweredHot!Initialize multiple MCP4728 I2C slaves with the same address

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AnalogArsonist
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2019/08/19 17:17:37 (permalink)
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Initialize multiple MCP4728 I2C slaves with the same address

Someone posted this question in like 2013 with same subject line but I didn't see a clear answer. If I have multiple MCP4728 devices on a shared I2C bus, each with the same address, can I program the address of each device by using their respective LDAC pins? For example, if I had four devices on the same I2C bus all coming from the factory with an address of 0h, can I program new addresses into each device from a test header with the following pins?
1. SDA
2. SCL
3. LDAC1
4. LDAC2
5. LDAC3
6. LDAC4
 
The datasheet seems to imply it's possible, but I want to make sure before building boards.
 
Thanks!
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mbrowning
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/08/22 15:18:12 (permalink)
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Why do you think the datasheet only implies? Seems pretty explicit to me
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Gort2015
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/08/22 15:32:26 (permalink)
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If it's in the specs...

MPLab X playing up, bug in your code? Nevermind, Star Trek:Discovery will be with us soon.
https://www.youtube.com/watch?v=Iu1qa8N2ID0
+ ST:Continues, "What Ships are Made for", Q's back.
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NKurzman
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/08/22 15:32:45 (permalink) ☼ Best Answerby analog arsonist 2019/09/24 17:21:57
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Yes it works but the I2C in not standard. You need to make some modified I2C to do the change.
You can do it from the CPU controlling them too.
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AnalogArsonist
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/09/24 17:21:39 (permalink)
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Yes, for a single device it is. I had concerns with multiple devices. Thanks?
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AnalogArsonist
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/09/24 17:22:40 (permalink)
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Thanks.. figured it'd be done with an MCU. I'll look around for a driver.
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NKurzman
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Re: Initialize multiple MCP4728 I2C slaves with the same address 2019/09/24 17:36:46 (permalink)
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I doubt you will find a Driver.  It is not Standard I2C.  It needs to be Bit Banged.
You can Buy them pre-addressed.
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