ESP32-S2 single core lower cost model announced

[thmjpr]

https://www.espressif.com/en/news/espressif-announces-%E2%80%A8esp32-s2-secure-wi-fi-mcu

Features
    Xtensa® single-core 32-bit LX7 microcontroller
    Clock frequency of up to 240 MHz
    Ultra-low-power co-processor
    320 kB SRAM, 128 kB ROM, 16 KB RTC memory (vs 520kB on ESP32)
    Wi-Fi 802.11 b/g/n (vs wifi + BT on ESP32)

IO Peripherals
    43 programmable GPIOs
    14 capacitive touch sensing IOs (vs 10 on ESP32)
    Standard peripherals including SPI, I2C, I2S, UART, ADC/DAC and PWM
    LCD (8-bit parallel RGB/8080/6800) interface and also support for 16/24-bit parallel
    Camera interface supports 8 or 16-bit DVP image sensor, with clock frequency of up to 40 MHz
    Full speed USB OTG support

Security
    RSA-3072-based trusted application boot
    AES256-XTS-based flash encryption to protect sensitive data at rest
    4096-bit eFUSE memory with 2048 bits available for application
    Digital signature peripheral for secure storage of private keys and generation of RSA signatures

Optimal Power Consumption
ESP32-S2 supports fine resolution power control through a selection of clock frequency, duty cycle, Wi-Fi operating modes and individual power control of its internal components.

    When Wi-Fi is enabled, the chip automatically powers on or off the RF transceiver only when needed, thereby reducing the overall power consumption of the system.
    ULP co-processor with less than 5 uA idle mode and 24 uA at 1% duty-cycle current consumption. (vs 10uA on ESP32).
    Improved Wi-Fi-connected and MCU-idle-mode power consumption.

Apparently they already released a single core version last year:
https://www.mouser.com/ProductDetail/Espressif-Systems/ESP32-SOLO-1?qs=w%2Fv1CP2dgqpIFRWX9FvikA==
https://blog.hackster.io/a-cheaper-single-core-esp32-module-53fa9c4143b5

ESP8266 is about $1 in low quantities (maybe less?), ESP32 chip is $2.50. So I would think it would fall somewhere between the two.

Or digikey prices:
https://www.digikey.ca/product-detail/en/espressif-systems/ESP8266EX/1904-1001-2-ND/8028401 $1.85
https://www.digikey.ca/product-detail/en/espressif-systems/ESP32-D0WD/1904-1003-1-ND/8028410 $3.50

trend vs 8266: https://trends.google.com/trends/explore?date=today%205-y&geo=US&q=esp32,esp8266

Is USB OTG that useful here?

[PCB.Wiz]

It also says
Engineering Samples of ESP32-S2 beta will be available in June
so still a little ways from being a real stocked product.

[Dielectric]

Sure, USB OTG is actually a great addition.  Almost every board has some kind of USB->UART chip on there, if they give us USB CDC support then those parts can go away.  USB Mass Storage would be neat too, if they're really going all-in with OTG and implementing USB Host support.

I wonder if they'll upgrade the ADC?  It's a little funny to use.  A basic 12-bit SAR like all of the M-class ARMs have would be better.

Blows my mind that we'll get an even cheaper ESP32.  They're stupid-cheap as it is.

[Rasz]

Did anyone decap it yet? Locking one of the cores and some ram/rom for internal use is the easy way of quickly introducing new "secure" product. Price drop might be just a function of economies of scale.

[sokoloff]

USB Host support (even if just for flash drives) at that price point would be a great addition for many applications.

[lucazader]

This chip is actually usign the newer LX7 core rather than the LX6 in the currently released esp32 variants.

However you may still be right, this might be a cut down version of a more beefy chip, eg maybe the full chip is a daul core with bluetooth, but they yeilds on the second core, or the bluetooth section are low, so they are disabling them for now and releasing this chip?
Who knows?

[PCB.Wiz]

Sure, USB OTG is actually a great addition.  Almost every board has some kind of USB->UART chip on there, if they give us USB CDC support then those parts can go away.  USB Mass Storage would be neat too, if they're really going all-in with OTG and implementing USB Host support.

Yup, shame it is only FS-USB tho (12MHz) and not HS-USB (480MHz), as that rather limits the much higher WiFi speed the rest of the device can support.
I've seen a couple of WiFi parts spec HS-USB which seems a better match.  Likely comes down to price, but if someone else does HS-USB they could get better volumes....

[lucazader]

When they were asking the community about more features or upgrades to a next gen chip they got a lot of suggestions.
a few have been included.
However they did say that putting a HS phy in the chip would ahve taken a very large area of silicon compared to the FS phy. So their engineers opted for that instead. I tried to convince them to at least implement a ULPI interface like on most higher end ST chips, but it looks like they didn't end up doing that.

As far as the ADC, lots of user requested a better performing ADC, that was much more linear, so I'm hoping they have improved that.

It does suck that they have removed bluetooth, at least for my use case. However i will be the first to admit, having ble capability in the chip, but then having the minimum power consumption with bluetooth on of ~15-20mA (thats what it curretly is) isn't super ideal.

[OwO]

When they were asking the community about more features or upgrades to a next gen chip they got a lot of suggestions.
a few have been included.
However they did say that putting a HS phy in the chip would ahve taken a very large area of silicon compared to the FS phy. So their engineers opted for that instead. I tried to convince them to at least implement a ULPI interface like on most higher end ST chips, but it looks like they didn't end up doing that.

The original ESP32 is already very cheap, I just wish they would release a $5 mega-esp32 that has everything. External USB PHY is the way of the past, it uses way too many pins and takes up too much board area.