HMC394LP4 / 394LP4E v09.0114 GaAs HBT PROGRAMMABLE5-BIT COUNTER, DC - 2.2 GHzApplications Information 4 4 Simplified Block Diagram t t M M s s s - s - r r o o t t c c e e t t e e s & D s & D r r e e iD iD iv Asynchronous Programming iv y D The 5-Bit programmable counter counts-down from the programmed value of the data bits to zero and issues an y D c output pulse at the end of each cycle. Settling time of the programmable 5-Bit counter is defined as the maximum c n time required for the counter to change the division ratio N to a new value after the data bits have settled. The worst n e case settling time occurs if the data bits A0 thru A4 are changing during the load cycle. Under this condition, the e u data bits may potential y be erroneous when they are clocked in and in the worst case could be all 1’s, requiring 32 u q clock cycles until the correct data is re-loaded into the flip flops. The worst case asynchronous settling time can be q e calculated as fol ows: e r T = 32/f (For Asynchronous Programming) r F SETTLING MAX IN F As an example, if the input frequency is 1 GHz, the maximum settling time is 32 nS Info F rmoatr p ion rfiurcne is , d hed ebly ivAe n r al y a og D n evd t ice o p s is bla eli c eve o ed t rd o b e e ras: H ccuratite tiatne M d reli iac bl reo . w Ho av wev e C er, n o o For price, delivery, and to place orders: Analog Devices, Inc., responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rporation, 20 Alpha Road, Chelmsford, MA 01824 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106 Phone: 978-250-3343 Fax: 978-250-3373 O rights of third parties that may result from its use. Specifications subject to change without notice. No P rd hone e r O : 7 n 81- -3li 2n 9 e a -47 t w 0 w 0 • O w rd .h e it r o t niltie n .c e ao t m license is granted by implication or otherwise under any patent or patent rights of Analog Devices. www.analog.com 4 - 8 Application Support: Pho Trademarks and registered trademarks are the property of their respective owners. ne: 978-250-33 A 4 p 3 o plica r a tio p n S p u s p @ po h rt itt : P ite ho . n c e o : 1m -800-ANALOG-D