14

8.0 AC INPUT ELECTRICAL CHARACTERISTICS (Pre- and Post-Radiation)*

Notes:

* Post-radiation performance guaranteed at 25

°C per MIL-STD-883 Method 1019.

1. Reference Figure 11 for clock output loading circuit that is equivalent to the load circuit used for all AC testing. The input waveform used to test these parameters

is shown in Figure 9.

2. Supplied only as a design guideline, neither tested nor guaranteed.

3. When driving the UT7R995C with a crystal, the XTAL1 pin does not define maximum input rise/fall time.

4. Although the input reference frequencies are defined as-low-as 2MHz, the N and R dividers must be selected to ensure the PLL operates from 24MHz-50MHz when

FS = LOW, 48MHz-100MHz when FS = MID, and 96MHz-200MHz when FS = HIGH.

5. The UT7R995C is guaranteed by characterization for quartz crystal frequencies ranging from 2MHz to 48MHz. Contact the factory for support using quartz crystals

that oscillate above 48MHz.

6. For the UT7R995C only, this parameter is guaranteed by characterization, but not tested.

7. For the UT7R995C only, this parameter is guaranteed by characterization, but only tested for frequencies <100 MHz.

Symbol

Description

Condition

Min.

Max.

Unit

2, 3

Input rise/fall time

VIH(min)-VIL(max)

--

20

ns/V

6

Input clock pulse

HIGH or LOW

2

--

ns

7

Input clock period

5

500

ns

6

Input clock duty cycle

HIGH or LOW

10

90

%

4, 5, 7

Digital reference input frequency

FS = LOW; PD/DIV = HIGH

2

50

MHz

FS = LOW; PD/DIV = MID

4

100

MHz

FS = MID; PD/DIV = HIGH

4

100

MHz

FS = MID; PD/DIV = MID

8

200

MHz

FS = HIGH; PD/DIV = HIGH

8

200

MHz

FS = HIGH; PD/DIV = MID

16

200

MHz