Datasheet

AD7294 Data Sheet
Rev. H | Page 2 of 48
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
General Description ......................................................................... 1
Revision History ............................................................................... 3
Functional Block Diagram .............................................................. 4
Specifications ..................................................................................... 5
DAC Specifications....................................................................... 5
ADC Specifications ...................................................................... 6
General Specifications ................................................................. 8
Timing Characteristics ................................................................ 9
Absolute Maximum Ratings .......................................................... 10
Thermal Resistance .................................................................... 10
ESD Caution ................................................................................ 10
Pin Configuration and Function Descriptions ........................... 11
Typical Performance Characteristics ........................................... 14
Terminology .................................................................................... 19
DAC Terminology ...................................................................... 19
ADC Terminology ...................................................................... 19
Theory of Operation ...................................................................... 20
ADC Overview ........................................................................... 20
ADC Transfer Functions ........................................................... 20
Analog Inputs .............................................................................. 20
Current Sensor ............................................................................ 22
Analog Comparator Loop ......................................................... 23
Temperature Sensor ................................................................... 24
DAC Operation ........................................................................... 25
ADC and DAC Reference .......................................................... 25
V
DRIVE
Feature .............................................................................. 26
Register Setting ............................................................................... 27
Address Pointer Register ........................................................... 27
Command Register (0x00) ........................................................ 28
Result Register (0x01) ................................................................ 28
T
SENSE
1, T
SENSE
2 Result Registers (0x02 and 0x03) ....................... 29
T
SENSE
INT Result Register (0x04).............................................. 29
DAC
A
, DAC
B
, DAC
C
, DAC
D
, Registers (0x01 to 0x04) ............... 30
Alert Status Register A (0x05), Register B (0x06), and
Register C (0x07) ........................................................................ 30
Channel Sequence Register (0x08) .......................................... 30
Configuration Register (0x09) .................................................. 31
Power-Down Register (0x0A) ................................................... 32
DATA
HIGH
/DATA
LOW
Registers: 0x0B, 0x0C (V
IN
0); 0x0E, 0x0F
(V
IN
1); 0x11, 0x12 (V
IN
2); 0x14, 0x15 (V
IN
3) .............................. 32
Hysteresis Registers: 0x0D (V
IN
0), 0x10 (V
IN
1), 0x13 (V
IN
2),
0x16 (V
IN
3) .................................................................................. 32
T
SENSE
Offset Registers (0x26 and 0x27) ................................... 33
I
2
C Interface .................................................................................... 34
General I
2
C Timing .................................................................... 34
Serial Bus Address Byte ............................................................. 35
Interface Protocol ....................................................................... 35
Modes of Operation ....................................................................... 39
Command Mode ........................................................................ 39
Autocycle Mode .......................................................................... 40
Alerts and Limits Theory .............................................................. 41
Alert_Flag Bit .............................................................................. 41
Alert Status Registers ................................................................. 41
Data
HIGH
and Data
LOW
Monitoring Features ............................ 41
Hysteresis ..................................................................................... 42
Applications Information .............................................................. 43
Base Station Power Amplifier Monitor and Control ............. 43
Gain Control of Power Amplifier ............................................. 44
Layout and Configuration ............................................................. 45
Power Supply Bypassing and Grounding ................................ 45
Outline Dimensions ....................................................................... 46
Ordering Guide .......................................................................... 47