and/or fractional divides are allowed on two of the PLLs.
There are a total of four 8-bit output dividers.The outputs
are connected to the PLLs via a switch matrix. The switch
matrix allows the user to route the PLL outputs to any
output bank. This feature can be used to simplify and
optimize the board layout. In addition, each output's slew
rate and enable/disable function is programmable.
IDT5V19EE404
Features
•
•
•
•
•
•
Four internal PLLs
Internal non-volatile EEPROM
Fast (400kHz) mode I
2
C serial interface
Input frequency range: 1 MHz to 200 MHz
Output frequency range: 4.9 kHz to 200 MHz
Reference crystal input with programmable linear load
capacitance
– Crystal frequency range: 8 MHz to 50 MHz
•
Integrated VCXO
•
Two independently controlled VDDO (1.8V - 3.3V)
•
Each PLL has a 7-bit reference divider and a 12-bit
feedback-divider
•
8-bit output-divider blocks
•
Fractional division capability on one PLL
•
Two of the PLLs support spread spectrum generation
capability
•
I/O Standards:
– Outputs - 1.8 - 3.3 V LVTTL/ LVCMOS
– Inputs - 3.3 V LVTTL/ LVCMOS
•
•
•
•
•
•
•
•
•
Programmable slew rate control
Programmable loop bandwidth
Programmable output inversion to reduce bimodal jitter
Redundant clock inputs with auto and manual switchover
options
Individual output enable/disable
Power-down mode
3.3V core V
DD
Available in VFQFPN package
-40 to +85°C Industrial Temp operation
IDT®
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
1
IDT5V19EE404
REV M 092412
IDT5V19EE404
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
CLOCK SYNTHESIZER
Functional Block Diagram
XIN/REF
XOUT
PLL0 (SS)
VCXO
VIN
controlled
Logic
S
R
C
1
S
R
C
2
S1
/DIV1
OUT1
CLKIN
PLL1
/DIV2
OUT2
CLKSEL
PLL2
PLL3 (SS)
S
R
C
3
S
R
C
6
S3
/DIV3
OUT3
SD/OE
SDA
SCL
SEL[2:0]
Control
Logic
/DIV6
OUT6
1. CLKIN, CLKSEL, SD/OE and SEL[2:0] have pull down resistors.
IDT®
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
2
IDT5V19EE404
REV M 092412
IDT5V19EE404
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
CLOCK SYNTHESIZER
Pin Configuration
SD/OE
SEL0
SEL1
GND
SEL2
19
VDD
VIN
XOUT
XIN/REF
VDDX
CLKIN
GND
1
VDDO3
OUT3
OUT6
GND
AVDD
13
7
CLKSEL
OUT2
VDDO1
OUT1
SDAT
24-pin QFN
Pin Descriptions
Pin#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Pin Name
VIN
XOUT
XIN / REF
SCLK
VDD
I/O
I
O
I
Pin Type
LVTTL
LVTTL
LVTTL
Power
Pin Description
VCXO analog control voltage input. Pulls output
±
100ppm by
varying from 0V to 3.3V.
CRYSTAL_OUT -- Reference crystal feedback.
CRYSTAL_IN -- Reference crystal input or external reference clock
input.
Crystal oscillator power supply. Connect to 3.3V through 5Ω
resistor. Use filtered analog power supply if available.
Input clock. Weak internal pull down resistor.
Connect to Ground.
Configurable clock output 1. Output levels controlled by VDDO1.
Configurable clock output 2. Output levels controlled by VDDO1.
Device power supply. Connect to 1.8 to 3.3V. Sets output voltage
levels for OUT1 and OUT2.
Device power supply. Connect to 3.3V.
Bidirectional I
2
C data. An external pull-up resistor is required. See
I
2
C specification for pull-up value recommendation.
I
2
C clock. An external pull-up resistor is required. See I
2
C
specification for pull-up value recommendation.
Input clock selector. Weak internal pull down resistor.
Device analog power supply. Connect to 3.3V. Use filtered analog
power supply if available.
Connect to Ground.
VDDx
CLKIN
GND
OUT1
OUT2
O
O
I
LVTTL
Power
LVTTL
LVTTL
Power
Power
VDDO1
V
DD
SDAT
SCLK
CLKSEL
AVDD
GND
I/O
I
I
Open Drain
LVTTL
LVTTL
Power
Power
IDT®
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
3
IDT5V19EE404
REV M 092412
IDT5V19EE404
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
CLOCK SYNTHESIZER
Pin#
16
17
18
19
20
21
22
Pin Name
OUT6
OUT3
I/O
O
O
Pin Type
LVTTL
LVTTL
Power
Pin Description
Configurable clock output 6. Output levels controlled by VDDO3.
Configurable clock output 3. Output levels controlled by VDDO3.
Device power supply. Connect to 1.8 to 3.3V. Sets output voltage
levels for OUT3 and OUT6.
Configuration select pin. Weak internal pull down resistor.
Configuration select pin. Weak internal pull down resistor.
Configuration select pin. Weak internal pull down resistor.
Enables/disables the outputs or powers down the chip. The SP bit
(0x02) controls the polarity of the signal to be either active HIGH or
LOW. (Default is active LOW.) Weak internal pull down resistor.
Connect to Ground.
Device power supply. Connect to 3.3V.
VDDO3
SEL2
SEL1
SEL0
SD/OE
I
I
I
I
LVTTL
LVTTL
LVTTL
LVTTL
23
24
GND
Power
Power
V
DD
1. Analog power plane should be isolated from a 3.3V power plane through a ferrite bead.
2. Each power pin should have a dedicated 0.01µF de-coupling capacitor. Digital VDDs may be tied together.
3. Unused clock inputs (REFIN or CLKIN) must be pulled high or low - they cannot be left floating. If the crystal oscillator is not used, XOUT must be left floating.
IDT®
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
4
IDT5V19EE404
REV M 092412
IDT5V19EE404
EEPROM PROGRAMMABLE VCXO CLOCK GENERATOR
CLOCK SYNTHESIZER
PLL Features and Descriptions
7-bit
D
VCO
4-bit
A
12-bit
N
Sigm a-Delta
M odulator
PLL0 Block Diagram
7-bit
D
VCO
12-bit
N
PLL1, PLL2 and PLL3 Block Diagram
Pre-Divider
(D)
1
Values
PLL0
PLL1
PLL2
PLL3
1 - 127
1 - 127
1 - 127
3 - 127
Multiplier
(M)
2
Values
10 - 8206
1 - 4095
1 - 4095
12 - 4095
Programmable
Spread Spectrum
Loop Bandwidth Generation Capability
Yes
Yes
Yes
Yes
Yes
No
No
Yes
1.For PLL0, PLL1 and PLL2, D=0 means PLL power down. For PLL3, 0, 1, and 2 are DNU (do not use)
2.For PLL0, M = 2*N + A + 1 (for A > 0); M = 2*N (for A = 0); A < N-1. For PLL1, PLL2 and PLL3, M=N.
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