Suggestion for a good Logic Analyzer for monitoring LPDDR1 RAM - Page 1
Forum section: electronics / beginners

author: 00pointer
author_rank: Contributor
timestamp: July 12, 2019, 03:06:43 pm
content: Hi,I want to monitor communication between a 1GB LPDDR1 RAM running in 100Mhz (200Mhz) speed. I was wondering if there is any suggestion for a logic analyzer which is able to both monitor dataline and address lines in the RAM while I intercept the communication between CPU and RAM.Any suggestion?

author: MarkL
author_rank: Unknown
timestamp: July 12, 2019, 05:03:00 pm
content: Are you trying to monitor a DDR module, or a single chip? What module or chip?How much data do you need to capture in a single shot?One suggestion is the Agilent 167xx series equipped with the appropriate type and number of cards (such as 16752A). It has synchronous capture and can do dual samples per clock cycle (a feature specifically for DDR). It can also adjust the skew of the sample point for each monitored input, which you may need.Tektronix has similar offerings, but I'm not familiar enough with their product line.Probing all those signals while maintaining good signal fidelity can be a challenge.

author: 00pointer
author_rank: Contributor
timestamp: July 12, 2019, 09:04:21 pm
content: Dear Mark,Thanks for the answer.I am trying to monitor a single Winbond W94AD2KB LPDDR SDRAM. I need to capture as much as possible data. If possible every data passing via RAM to CPU and from CPU to RAM. I need to know the memory address which CPU fetch and data which it gets and place it into its L2 cache.About Agilent do you refer to Agilent 16700B?

author: MarkL
author_rank: Unknown
timestamp: July 13, 2019, 02:16:43 pm
content: Assuming you're not looking for something new, I was actually thinking of the 16702B which has a built-in LCD screen. The 16700B would also work fine if you don't mind an external monitor or connecting to the analyzer from your computer. If you're interested in this series get one with option 003 which has more memory.Another possibility is the 16900 series, which runs windows and has a faster processor. But it is more expensive.For either, the 16752A card in state mode can capture a max of 32M samples at 400MHz with a width of 68 bits. I haven't mapped out all the W94AD2KB signals, but it might all fit on one card. If not, you can gang two cards together.But more importantly, the W94AD2KB is a 90-ball VFBGA. Are you able to get access to all the signals? Are they exposed on the board somewhere? Does the board have built-in probing connections?

author: 00pointer
author_rank: Contributor
timestamp: July 14, 2019, 07:51:48 pm
content: Hi Mark, Thanks for the suggestions.Well, W94AD2KB has both 63 and 90 VFBGA configurations. The PCB I am looking into use it in a 63 configuration and obviously I do not need to connect all pins in this 63 mode. Even in 63 mode majority of pins are not connected or are ground.Yes I am able to access to all signal pins since they are exposed. No the board does not have a probing connection but I created a custom board which can connect to the PCB.

author: MarkL
author_rank: Unknown
timestamp: July 15, 2019, 02:57:40 am
content: I was going by the datasheet here:https://www.winbond.com/resource-files/w94adxkb_datasheet_pkg_a01-005_20141002.pdfIn the table on page 5, all the xxxxx2KB part numbers are 32 bits wide and are 90-ball. By "63 mode", are you saying you're just going to use 16 bits?

author: 00pointer
author_rank: Contributor
timestamp: July 15, 2019, 08:31:44 am
content: Hi Mark,You are indeed right. I made a confusion with another unrelated project with with a NAND flash. It is indeed 90 VFBGA.In case other looking into this, I also notice a company which make special equipment for DDR/LPDDR/DRAM analysis. It is called FuturePlus.