I've created a microwave counter using an HMC679 chip followed by 4 HMC492 chips, driving more ( common ) ECL chips.
Initial tests showed all the HMC492 chips were failed and had to be replaced. I attributed this to the soldering process ( oven reflow…
Hello,
| I'm using the following parts HMC573LC3B, HMC492LP3E, and HMC905LP3E | |
and I need to know the noise power levels for each device when no input signals is applied, but the power supplies are on. Could you… |
I've made a microwave freq counter using ( among others ) four HMC492 chips. The counter seems to work properly, each of the 492 chips seems to divide the input frequency by exactly two, as expected. Scope observations of the chip output signals also…
使用HMC733和HMC702和分频器HMC492产生16GHz的信号，参考频率 120MHz，鉴相频率60MHz。我计算环路参数的时候需要将Kv除以2吗？因为VCO输出的频率经过功分和分频之后返回到HMC702的VCOIN端。
Hi Eric,
In the past we have found that 8.25k was the appropriate value to prevent self oscillation without RF input for the HMC492, HMC493, and HMC494.
Best Regards,
David
我们现在大量用ADF5000系列替代HMC492系列了，以前用的时候容易被烧掉，而且高低温下没有ADF5000系列好用。建议你更换成ADF5000系列的。当然我不知道你的使用环境哈，我们常用在锁相环里。
Hi there,
Some dividers will self-oscillate in the absence of an RF input signal. For the HMC492, 493 and 494 dividers a shunt 8.25k ohm resistor placed on one of the differential inputs was the appropriate value to prevent self oscillation.
Hi,
The HMC492 frequency divider output will be a square wave with strong odd harmonics. If you wish, you can low pass or band pass filter the output to achieve a sine wave.
Generally speaking, most frequency dividers/counters are edge triggered logic…
Some of the other HMC dividers have an input network similar to what you described (as an example HMC705 or HMC492), but this part went a different route for some reason. I also would tend to agree with you the /IN naming convention.
In regards to the diagram…
| HMC928 |
| HMC929 |
| HMC931 |
| HMC932 |
| HMC933 |
| HMC934 |
| HMC935 |
| HMC247G |
| HMC538 |
| HMC-C018G |
| HMC-C025G |
| HMC-C053G |
| HMC-C584G |
| HMC7056G |
| HMC7054G |
| HMC7053G |
| HMC7056AG |
| HMC642G |
| HMC642AG |
| HMC643G |
| HMC644AG |
| HMC647 |
| HMC647A |
