Page 1 of 1

Using HEDS 5500 in combination with DC Motor Phidget (ID: DCC1000_0)

Posted: Thu Apr 14, 2022 8:12 am
by janvanhulzen
Hi,

i have a DC Motor Phidget (ID: DCC1000_0) and want to combine this with a motor featuring a Avago/HP HEDS 5500 encoder. According to the datasheet this encoder has internal comparators which should be able to drive a TTL load. To improve rise time 3.2 kOhm pull up resistors may be added. In the encoder primer published on this website it is stated that the interface should work by selecting the open collector version and selecting a pull up resistor R which can be calculated using 1/R=1/Rr-1/Re where Rr is the required pull up resistor and Re the pull up resistor included in the interface of the phidget. Unfortunately, no value of Re is specified.

I would like to get some guidance on how to use the HEDS 5500 with my phidget if available or the value of Re that should be used in the calculation of the proper pull up resistor to be included.

with Kind regards,

Jan van Hulzen