we can not get S-882Z.....

[maxever]

Hello guys. I am a student from UESTC, China,and I am very interest in WISP5. In China ,we can't get the S-882Z, is there any other device can replace it？

Hi maxever,

Great question! In fact, the Seiko S-882Z was recently discontinued and is not available anywhere! This is obviously a problem for those hoping to build their own WISP5-LRG. There is no direct replacement part available for this sort of highly sensitive DC-DC charge pump... we've exhaustively searched as of several months ago.

You have at least three options:

1. Request preassembled WISP5-LRG devices from us (no charge for academic collaborators) at mailwisp@gmail.com. There is typically a limit of three devices per lab or project.
2. You can wait until we have open sourced the design for the WISP5-HPW, which does not make use of the Seiko S-882Z. It will instead make use of a classic RF Dickson charge pump with discrete diodes... see the old WISP4.1 design files for an example of what the classic RF Dickson charge pump will look like.
3. You can attempt to modify the design to make use of the BQ25570, an inductive charge management IC we've found to be almost as effective as the S-882Z but which requires a very different topology. See our paper "WISPCam: A Battery-Free RFID Camera" (http://ben.ransford.org/papers/rfid15-wispcam.pdf) in which our design makes use of the BQ25570.

[csqjxiao]

Hi, Anparks:

I am a researcher coming from the Southeast University of China, and quite interested in projects about the energy harvesting WISP5 tags. I wonder whether the WISP5 HPW tags are ready for purchase right now. I saw on the following Q&A page, showing that the 3-stage Dickson charge pump (with external voltage supervisory ICs) may have better harvesting performance than the 1-stage Seiko S-882Z.
http://wisp5.wikispaces.com/share/view/73650110

Thanks for your kind help.

Qingjun Xiao

Hi Qingjun,

No, the reason we went with the S-882Z is that it does in fact have better range performance than the N-stage discrete diode charge pump. The discrete charge pump performs more efficiently at higher power levels (short range).

We have not completed the WISP5-HPW yet; we haven't actually seen much interest in it.

In other news, we have "heard rumors" that the S-882Z or a similar pin-compatible product from Seiko IC might become available again soon.

Best regards,
Aaron

[alexeicolin]

Would this one work? S-8823A. Appears to have the same pinout as S-882Z.

The 2.2V version is in stock at chip1stop.com in Japan. I sent a request for quote for the 2.4V version. UPDATE: no stock for 2.4V.

[TheaperDeng]

Would this one work? S-8823A. Appears to have the same pinout as S-882Z.

The 2.2V version is in stock at chip1stop.com in Japan. I sent a request for quote for the 2.4V version. UPDATE: no stock for 2.4V.

So, how did you solve this problem? (Can't get S-882Z)

[SAKURA1998]

      Hello guys.  I am a student from UESTC, China,and I am very interest in WISP5. In China ,we can't get the S-882Z, is there any other device can  replace it？

Did you manage to get this component, or some other method to get this WISP-LRG?

Actually, the S-8880A and S-8823A are new pin-compatible replacements for the S-882Z. The 2.4 version of the S-8880A is the best option. You may have success in ordering samples direct from Seiko if they are not available from distributors.

[SAKURA1998]

Thanks for your apply! But in China, we can not get S-8880A24. Could S-8823A24 (2.4 V version of S-8823A) be used? Seiko company said that S-882Z could be replace with S-8823A. Why S-8880A is the best option? Many thanks! 发件人: Aaron Parks 发送时间: 2018年10月22日 9:42 收件人: wisp/wisp5-hw 抄送: SAKURA1998; Comment 主题: Re: [wisp/wisp5-hw] we can not get S-882Z..... (#2) Actually, the S-8880A and S-8823A are new pin-compatible replacements for the S-882Z. The 2.4 version of the S-8880A is the best option. You may have success in ordering samples direct from Seiko if they are not available from distributors. — You are receiving this because you commented. Reply to this email directly, view it on GitHub, or mute the thread.

Sure, as far as I know you can use the S-8823A24. If I remember correctly, the two have slightly different standby mode current consumption, with the 8880A slightly lower, but other than that they appear to be identical:

https://www.ablic.com/en/semicon/products/power-management-ic/charge-pump-ic/

[Pongoid]

Any luck sourcing replacements for the Seiko/ABLIC parts since they appear to have discontinued all of their ultra low voltage charge pumps? I'd rather not use any inductors or transformers if at all possible.

Thank you in advance.