generation of 16-bit PWM

Does anybody know a chip (not MCU) that generates one or more PWM-signals with more than 12-bit resolution and accepts I²C, SPI, ... from an MCU.

I can only find 8-bit PWM devices from Philips and National, and MCU's with 16-bit PWM. Reprogramming the code for another brand of MCU (with

Greets.

Then you'll need to use an MCU. Best bet is Atmel ATmega with two 16-bit timers with PWM and two 8-bit timers also with PWM.

JOhn

Or joble can use triple 16-bit timer/counter ICs like Intel's 82c54 design. These venerable triple timers are wholly-contained within the VLSI chips used to make all our everyday IBM-compatible PCs, but IC companies such as Intersil, still manufacture them. The cp82c54-12 version ($8.99 at DigiKey) can be operated at 12MHz, which means the 16-bit PWM repetition frequency will be a rather slow 183Hz. That low PWM frequency explains the relative lack of enthusiasm for 16-bit PWM designs. In contrast, a 12-bit PWM with a 12MHz clock cycles at 2.9kHz, and an 8-bit PWM at 47kHz. Another problem with high-bit-density approaches is the high PWM frequency necessary to get these very low cycles rates: switching a PWM power load at a 12MHz rate implies fast sub-50ns switching times, and even worse, high power-switching repetition rates, which can stress power circuitry.

joble snipped-for-privacy@hotmail.com schrieb:

It will be hard to find dedicated PWM chips, since today a properly matching MPU (with on-chip PWM) will be used for new developments. I don't know about such chips with more than 8 bits, and I fear there are none.

If you don't want to add a second MPU just for generating the PWM, you might think about using a small CPLD - an XC9572XL for example should be sufficient for a 16-bit PWM generator with SPI interface.

TI has some new products for digital power supplies.... Fusion is the coined name. But, none are spi to pwm. I would go to sourceforge and see if there are any open source pwm controllers. Last time I looked there was an unfinished project. In any event it should be strainght forward to roll your own.

Cheers

Does anybody know a chip (not MCU) that generates one or more PWM-signals with more than 12-bit resolution and accepts I²C, SPI, ... from an MCU.

I can only find 8-bit PWM devices from Philips and National, and MCU's with 16-bit PWM. Reprogramming the code for another brand of MCU (with

Greets.

Hello,

It might be the only option. I don't think there is enough of a market for a stand-alone 16bit PWM that anyone would fund a chip design for that.

Regards, Joerg