REVISION B 07/20/15

2

FEMTOCLOCK®CRYSTAL-TO-CML CLOCK GENERATOR

845264 DATA SHEET

Pin Descriptions and Characteristics

Table 1. Pin Descriptions

NOTE: Pulldown and Pullup refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.

Table 2. Pin Characteristics

Number

Name

Type

Description

1, 2

nQA0, QA0

Output

Bank A differential clock output pair. CML interface levels.

3, 17

VDD

Power

Core supply pins.

4

nOEA

Input

Pulldown

Output enable pin for Bank A outputs. See Table 3E for function.

LVCMOS/LVTTL interface levels.

5, 6, 7, 8, 9,

16, 25, 32

nc

Unused

Do not connect.

10

VDDA

Power

Analog supply pin.

11

nBYPASS

Input

Pullup

PLL bypass pin. See Table 3D for function. LVCMOS/LVTTL interface levels.

12

REF_CLK

Input

Pulldown

Single-ended reference clock input. LVCMOS/LVTTL interface levels.

13, 29

GND

Power

Power supply ground.

14,

15

XTAL_OUT,

XTAL_IN

Input

Crystal oscillator interface. XTAL_IN is the input, XTAL_OUT is the output.

18,

19

FSELB0,

FSELB1

Input

Pulldown

Output frequency divider select enable pins for Bank B outputs.

See Table 3C for function. LVCMOS/LVTTL interface levels.

20,

21

FSELA0,

FSELA1

Input

Pulldown

Output frequency divider select enable pins for Bank A outputs.

See Table 3B for function. LVCMOS/LVTTL interface levels.

22

REF_SEL

Input

Pulldown

PLL reference clock select pin. See Table 3A for function.

LVCMOS/LVTTL interface levels.

23, 24

QB0, nQB0

Output

Bank B differential clock output pair. CML interface levels.

26

nOEB

Input

Pulldown

Output enable pin for Bank B outputs. See Table 3F for function.

LVCMOS/LVTTL interface levels.

27, 28

nQB1, QB1

Output

Bank B differential clock output pair. CML interface levels.

30, 31

nQA1, QA1

Output

Bank A differential clock output pair. CML interface levels.

Symbol

Parameter

Test Conditions

Minimum

Typical

Maximum

Units

CIN

Input

Capacitance

nBYPASS,

REF_SEL,

nOEA, nOEB,

FSELB0, FSELB1,

FSELA0, FSELA1

4pF

RPULLDOWN

Input Pulldown Resistor

51

k



RPULLUP

Input Pullup Resistor

51

k

