AD9549APCBZ datasheet(12/76 Pages) AD

12 / 76 page

AD9549

Rev. D | Page 12 of 76

Pin No.

Input/

Output

Pin Type

Mnemonic

Description

3.3 V CMOS

IO_UPDATE

I/O Update. A logic transition from 0 to 1 on this pin transfers data from the I/O

port registers to the control registers (see the Write section). This pin has an

internal 50 kΩ pull-down resistor.

3.3 V CMOS

CSB

Chip Select. Active low. When programming a device, this pin must be held

low. In systems where more than one AD9549 is present, this pin enables

individual programming of each AD9549. This pin has an internal 100 kΩ pull-

up resistor.

3.3 V CMOS

SDO

Serial Data Output. When the device is in 3-wire mode, data is read on this pin.

There is no internal pull-up/pull-down resistor on this pin.

I/O

3.3 V CMOS

SDIO

Serial Data Input/Output. When the device is in 3-wire mode, data is written

via this pin. In 2-wire mode, data reads and writes both occur on this pin. There

is no internal pull-up/pull-down resistor on this pin.

3.3 V CMOS

SCLK

Serial Programming Clock. Data clock for serial programming. This pin has an

internal 50 kΩ pull-down resistor.

Exposed

Die Pad

GND

EPAD

Analog Ground. The exposed thermal pad on the bottom of the package pro-

vides the analog ground for the part. This exposed pad must be connected to

ground for proper operation.

AD9549APCBZ 데이터시트(PDF) 12 Page - Analog Devices