> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# Adafruit S-35710 Low-Power Wake Up Timer Breakout - STEMMA QT / Qwiic

**Type:** Product page · **SKU:** ADA5959 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/adafruit-s-35710-low-power-wake-up-timer-breakout-stemma-qt-qwiic.html ([markdown](https://core-electronics.com.au/adafruit-s-35710-low-power-wake-up-timer-breakout-stemma-qt-qwiic.html.md))

The Adafruit S-35710 Wake Up Timer is a low power 'watchdog timer' chip that can be programmed to alert with a digitally-configurable alarm from 1...

## Pricing

- **Price:** $8.80 (inc GST) — $8.00 AUD, exc GST
- **Quantity discounts:** 10+ $7.76 (exc GST) · 50+ $7.60 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Sep 01 and Sep 07.

## How to buy

- **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=ADA5959:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart.
- **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/ADA5959:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.)
- **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there.
- **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works)
- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## Description

The **Adafruit S-35710 Wake Up Timer** is a low power 'watchdog timer' chip that can be programmed to alert with a digitally-configurable alarm from 1 second up to 194 days, thanks to a 24-bit second counter. It's an interesting alternative to a real time clock or internal sleep timer and might be useful for some ultra-low-power projects that want to have a separate (and possibly separately-powered) chip to handle time-keeping and alarms. [Adafruit covered this component on EYE ON NPI and thought it would make for a nice breakout in the shop](https://www.youtube.com/watch?v=htl2uyHUViM).

Usage is pretty simple: on I2C write of the timer register, the chip starts counting from 0 seconds up and the OUT pin goes high. When the count matches the timer register, the OUT pin goes low. Simple, and like Adafruit mentioned, it's very low power, drawing only 0.2uA. The output is open-drain, and if you want to have it be inverted, there's a switch that will put the signal through an N-channel FET so the polarity goes the other way.

One thing to note, is that on power-up the OUT line is default low, which means its not good for a low-power sleep manager, only for watch-dog-like timings. That is to say, you cannot connect this to your microcontroller's reset or enable line to self-depower because it will be disabled/reset when powered up. Still, maybe a useful chip for some folks who want to signal after a long delay or have a more complex power management scheme.

To get you going fast, Adafruit spun up a custom-made PCB in the[ **STEMMA QT** form factor](https://core-electronics.com.au/search?q=stemma%20qt%20sensor), making it easy to interface with. The [STEMMA QT connectors](https://learn.adafruit.com/introducing-adafruit-stemma-qt/what-is-stemma-qt) on either side are compatible with the [SparkFun Qwiic](https://core-electronics.com.au/catalogsearch/result/?q=qwiic) I2C connectors. This allows you to make solderless connections between your development board and the S-35710 or to chain it with a wide range of other sensors and accessories using a [**compatible cable**](https://core-electronics.com.au/search?q=stemma%20qt%20cable).

## Technical Details 

![RoHS 2 2011 65 EU Compliant](https://core-electronics.com.au/attachments/localcontent/RoHS2_2011_65_EU_7356c5574c.svg)![RoHS 2 2015 863 EU Compliant](https://core-electronics.com.au/attachments/localcontent/RoHS2_2015_863_EU_86773f57f9.svg)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/A/D/ADA5959-1.jpg)
