Data Sheet
AD9523
Rev. C | Page 15 of 60
Pin
No.
Mnemonic
Description
46
OUT6
O
Complementary Square Wave Clocking Output 6. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
47
OUT6
O
Square Wave Clocking Output 6. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
48
VDD1.8_OUT[6:7]
P
1.8 V Supply for Output 6 and Output 7 Clock Dividers.
49
OUT5
O
Complementary Square Wave Clocking Output 5. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
50
OUT5
O
Square Wave Clocking Output 5. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
51
VDD3_OUT[4:5]
P
3.3 V Supply for Output 4 and Output 5 Clock Drivers.
52
OUT4
O
Complementary Square Wave Clocking Output 4. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
53
OUT4
O
Square Wave Clocking Output 4. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
54
VDD1.8_OUT[4:5]
P
1.8 V Supply for Output 4 and Output 5 Clock Dividers.
55
STATUS1/SP1
I/O
Lock Detect and Other Status Signals (STATUS1)/I2C Address (SP1). This pin has an internal 40 kΩ pull-
down resistor.
56
STATUS0/SP0
I/O
Lock Detect and Other Status Signals (STATUS0)/I2C Address (SP0). This pin has an internal 40 kΩ pull-
down resistor.
57
EEPROM_SEL
I
EEPROM Select. Setting this pin high selects the register values stored in the internal EEPROM to be
loaded at reset and/or power-up. Setting this pin low causes the AD9523 to load the hard-coded
default register values at power-up/reset. This pin has an internal 40 kΩ pull-down resistor.
58
OUT3
O
Complementary Square Wave Clocking Output 3. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
59
OUT3
O
Square Wave Clocking Output 3. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
60
VDD3_OUT[2:3]
P
3.3 V Supply for Output 2 and Output 3 Clock Drivers.
61
OUT2
O
Complementary Square Wave Clocking Output 2. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
62
OUT2
O
Square Wave Clocking Output 2. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
63
VDD1.8_OUT[0:3]
P
1.8 V Supply for Output 0, Output 1, Output 2, and Output 3 Clock Dividers.
64
OUT1
O
Complementary Square Wave Clocking Output 1. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
65
OUT1
O
Square Wave Clocking Output 1. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
66
VDD3_OUT[0:1]
P
3.3 V Supply for Output 0 and Output 1 Clock Drivers.
67
OUT0
O
Complementary Square Wave Clocking Output 0. This pin can be configured as one side of
a differential LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
68
OUT0
O
Square Wave Clocking Output 0. This pin can be configured as one side of a differential LVPECL/
LVDS/HSTL output or as a single-ended CMOS output.
69
NC
P
This pin is not connected internally (see
Figure 2).70
ZD_IN
I
External Zero Delay Clock Input. Along with ZD_IN, this pin is the differential input for the PLL
reference. Alternatively, this pin can be programmed as a single-ended 3.3 V CMOS input.
71
ZD_IN
I
Complementary External Zero Delay Clock Input. Along with ZD_IN, this pin is the differential input
for the PLL reference. Alternatively, this pin can be programmed as a single-ended 3.3 V CMOS input.
72
PLL1_OUT
O
Single-Ended CMOS Output from PLL1. This pin has settings for weak and strong in Register 0x1BA,
EP
EP, GND
GND
Exposed Paddle. The exposed paddle is the ground connection on the chip. It must be soldered to
the analog ground of the PCB to ensure proper functionality and heat dissipation, noise, and
mechanical strength benefits.
1 P = power, I = input, O = output, I/O = input/output, P/O = power/output, GND = ground.