AD9524
Data Sheet
Rev. E | Page 14 of 56
Pin
No.
Mnemonic
Description
This pin has an internal 40 k pull-down resistor in SPI mode but is high impedance in IC mode.
17
SDIO/SDA
I/O
Serial Control Port Bidirectional Serial Data In/Data Out for SPI Mode (SDIO) or IC Mode (SDA).
18
SDO
O
Serial Data Output. Use this pin to read data in 4-wire mode (high impedance in 3-wire mode).
There is no internal pull-up/pull-down resistor on this pin.
19
OUT5
O
Complementary Clock Output 5. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
20
OUT5
O
Clock Output 5. This pin can be configured as one side of a differential LVPECL/LVDS/HSTL output or as a
single-ended CMOS output.
21
VDD3_OUT[4:5]
P
3.3 V Supply for Output 4 and Output 5 Clock Drivers.
22
OUT4
O
Complementary Clock Output 4. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
23
OUT4
O
Clock Output 4. This pin can be configured as one side of a differential LVPECL/LVDS/HSTL output or as a
single-ended CMOS output.
24
VDD1.8_OUT[4:5]
P
1.8 V Supply for Output 4 and Output 5 Clock Dividers.
25
REF_TEST
I
Test Input to PLL1 Phase Detector.
26
RESET
I
Digital Input, Active Low. Resets internal logic to default states. This pin has an internal
40 k pull-up resistor.
27
PD
Chip Power-Down, Active Low. This pin has an internal 40 k pull-up resistor.
28
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 t
hecoded default register values at power-up/reset. This pin has an internal 40 k pull-down resistor.
29
OUT3
O
Complementary Clock Output 3. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
30
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.
31
VDD3_OUT[2:3]
P
3.3 V Supply Output 2 and Supply Output 3 Clock Drivers.
32
OUT2
O
Complementary Clock Output 2. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
33
OUT2
O
Clock Output 2. This pin can be configured as one side of a differential LVPECL/LVDS/HSTL output or as a
single-ended CMOS output.
34
VDD1.8_OUT[2:3]
P
1.8 V Supply for Output 2 and Output 3 Clock Dividers.
35
STATUS1/SP1
I/O
Lock Detect and Other Status Signals (STATUS1)/I2C Address (SP1).
36
STATUS0/SP0
I/O
Lock Detect and Other Status Signals (STATUS0)/I2C Address (SP0).
37
OUT1
O
Complementary Clock Output 1. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
38
OUT1
O
Clock Output 1. This pin can be configured as one side of a differential LVPECL/LVDS/HSTL output or as a
single-ended CMOS output.
39
VDD3_OUT[0:1]
P
3.3 V Supply Output 0 and Supply Output 1 Clock Drivers.
40
OUT0
O
Complementary Clock Output 0. This pin can be configured as one side of a differential
LVPECL/LVDS/HSTL output or as a single-ended CMOS output.
41
OUT0
O
Clock Output 0. This pin can be configured as one side of a differential LVPECL/LVDS/HSTL output or as a
single-ended CMOS output.
42
VDD1.8_OUT[0:1]
P
1.8 V Supply for Output 0 and Output 1 Clock Dividers.
43
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.
44
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.
45
REF_SEL
I
Reference Input Select. This pin has an internal 40 k pull-down resistor.
46
PLL1_OUT
O
Single-Ended CMOS Output from PLL1. This pin has settings for weak and strong in
47
LDO_PLL1
P/O
1.8 V Internal LDO Regulator Decoupling Pin for PLL1. Connect a 0.47 F decoupling capacitor
from this pin to ground. Note that, for best performance, the LDO bypass capacitor must be
placed in close proximity to the device.
48
VDD3_PLL1
P
3.3 V Supply PLL1. Use the same supply as VCXO.
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.