Competitor to FTDI USB chips? - Page 1
Forum section: electronics / general

author: richardman
author_rank: Frequent Contributor
timestamp: September 18, 2018, 05:15:36 pm
content: For ease of use and longevity, FTDI USB chips seem to be the standard. Any new contenders showing up - I don't mean cheap clones ;-) but real alternatives. No particular needs but choices are always good right?

author: tsman
author_rank: Frequent Contributor
timestamp: September 18, 2018, 05:51:43 pm
content: SiLabs CP210x and the WCH CH340 are popular replacements for the FTDI UART chips. The CH340 is aimed at the China market though. When FTDI altered their driver to break countfeit FTDI chips, a lot of people switched away from them to one of those. There is also the MCP2210 from Microchip which is basically a preprogrammed PIC.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 18, 2018, 06:06:02 pm
content: Quote from: richardman on September 18, 2018, 05:15:36 pmThey're good for simple applications, but they don't have any accessible brains. So, an MCU with a USB module will beat FTDI chips in and out. The problem is that MCUs with High Speed USB (or USB 3.0) are rather complex and expensive. I don't really know of any cheap and simple MCU with High Speed USB support.Another problem with FTDI chips is that while serial FTDI drivers are built-in in Windows/Mac, more advanced things, such as MPSSE, require different FTDxx drivers which actually compete with serial FTDI drivers making things rather complicated.Long story short, FTDI chips are widely used not because they're incredibly good, but simply because it's often nothing else.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 18, 2018, 06:14:31 pm
content: FTDI chips just work. That's already a big plus.But the biggest plus they have is their quality and FREE drivers that are WHQL on Windows.If you're not targetting Windows platforms, this point is moot though as they use libusb both on Linux and MacOS. So Windows support would be my main decision factor here. Writing (or buying) good performance and bug-free drivers on Windows is either hard or could cost you an arm and a leg. Now if you're not using bulk transfers but use HID, you don't have this problem, and FTDI chips are not particularly ideal for HID (I'm not even sure they have chips that support HID - I'd have to check).Again if you're targetting Linux only, that's another story: I've gotten much better performance using libusb directly than using their Linux drivers (which are based on libusb but seem to be poorly written!)

author: NorthGuy
author_rank: Super Contributor
timestamp: September 18, 2018, 06:29:15 pm
content: Quote from: SiliconWizard on September 18, 2018, 06:14:31 pmI don't think so. No HID, no MSD, only serial or their own drivers.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 18, 2018, 06:43:47 pm
content: Quote from: NorthGuy on September 18, 2018, 06:29:15 pmI just checked and actually they have one:https://www.ftdichip.com/Products/ICs/FT260.htmlIt seems a bit limited, but it does exist.

author: jaromir
author_rank: Unknown
timestamp: September 18, 2018, 07:00:30 pm
content: Quote from: richardman on September 18, 2018, 05:15:36 pmIn one of my applications designed for FT232RL I used CY7C65213 as drop-in replacement and it was perfectly good for given application.As usual, it's worth checking datasheets.

author: nctnico
author_rank: Super Contributor
timestamp: September 18, 2018, 07:05:43 pm
content: Quote from: richardman on September 18, 2018, 05:15:36 pmThe latest Windows versions support almost all the serial to USB chips so you can pick whatever device you want. Due to FTDI gate I have stopped using chips from FTDI. I'm either using a microcontroller with a CDC port implementation or the Silabs CP21xx chips.

author: asmi
author_rank: Super Contributor
timestamp: September 18, 2018, 07:11:50 pm
content: I especially like they FT-X series, which are essentially bare USB-to-something chips that just work. Need to have a UART to talk to computer? Simple - FT230X will do that with bare minimum of pins and almost no external components required. Want more speed? FT221X for SPI-like or FT240X for FIFO bus will get you what you need. They have chips for I2C, SPI, UART and some other options - all in one series, with almost no external components required. And these chips are inexpensive.I also used FT601 to get USB 3.0 speeds - these are more costly, but they are still the cheapest option as far as I know to connect FPGA to computer.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 18, 2018, 07:50:38 pm
content: Quote from: SiliconWizard on September 18, 2018, 06:43:47 pmI haven't seen that one. Unfortunately, Full Speed only

author: PCB.Wiz
author_rank: Super Contributor
timestamp: September 18, 2018, 08:32:02 pm
content: Quote from: tsman on September 18, 2018, 05:51:43 pmSiLabs have a new CP2102N- which has higher top BAUD rates and FLASH reconfig.If you want to roll your own, there is EFM8UB1/UB2/UB3 USB micros from SiLabs.Exar have some good USB-UART bridges, theirs have a 9 bit mode, and have the highest FS-USB sustained throughput Baud rates we have measured.(but not as cheap as CP2102N, or as well stocked)The CH340 supplier also now has CH552/CH554/CH554/CH559, which are FLASH 8051 USB with quite low prices.https://www.electrodragon.com/?s=CH55&post_type=product

author: westfw
author_rank: Super Contributor
timestamp: September 18, 2018, 08:37:39 pm
content: Why would a serial converter chip need anything beyond “full speed”?

author: NorthGuy
author_rank: Super Contributor
timestamp: September 18, 2018, 08:57:59 pm
content: Quote from: westfw on September 18, 2018, 08:37:39 pmFor faster communications, of course. Full Speed is roughly 1MByte/s, and only 64KBytes/s if you use HID. With High Speed you can do almost 50MBytes/s, and 8MBytes/s with HID.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 18, 2018, 09:31:21 pm
content: Quote from: westfw on September 18, 2018, 08:37:39 pmBecause RS485.I routinely use multiple RS485 channels at up to 6MBaud.The FTx232H high-speed chips work well, though their driver could be better as it doesn't support transmit buffering in the host, so you need to be rather careful with packet sizes if you don't want the throughput severely limited by the driver blocking.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 18, 2018, 11:47:35 pm
content: Quote from: NorthGuy on September 18, 2018, 07:50:38 pmWell, it only has an I2C interface as I got it anyway?That said, I'm not sure HID devices can go higher than full speed anyway. I'm not 100% sure about recent versions of the USB standard but surely with older HID devices you couldn't go higher.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 18, 2018, 11:55:19 pm
content: Quote from: westfw on September 18, 2018, 08:37:39 pmWe were not just talking about serial converters as I reckon. The need for higher speeds in a lot of projects is obvious, and this is where FTDI chips give rather straightforward solutions, drivers included.Granted that for just "serial converters" at low speeds, you can find many chips out there, a lot of them being much cheaper than FTDI's parts and work fine.You're not going to get 30-40MBytes/s with a CP21xx and a virtual serial port driver. You will with a FT232H/FT2232H (and some others) in synchronous mode and the vendor's drivers in D2XX mode.You *can* get that kind of throughput with some MCUs which have embedded high-speed USB cores, but it's not going to be as straightforward most of the time.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 19, 2018, 02:58:54 am
content: Quote from: SiliconWizard on September 18, 2018, 11:47:35 pmThe datasheet quotes 12MBaud UART, although it's much faster than Full Speed HID can match.Quote from: SiliconWizard on September 18, 2018, 11:47:35 pmI'm sure you can do High Speed HID. HID itself is not linked to any particular speed bin. The HID speed is limited by the throughput of interrupt transfers.

author: technix
author_rank: Super Contributor
timestamp: September 19, 2018, 10:32:24 am
content: At least for me the STM32F042F4P6 and it’s bigger brother STM32F042F6P6 are interesting competitors. They are full 32-bit USB microcontrollers so versatility is never a problem. If you use GCC and skip CubeMX, I have 4kB unoptimized simple USB HID, 9kB unoptimized USB CDC (+stub HID) and a (yet to work fully) 24kB unoptimized USB CDC + CMSIS-DAP composite. (The above numbers are all pulled from DAP42 firmware in its various stages of development.)If you just need USB serial there is also Holtek HT42B534-1 which also speaks USB CDC.