ZSSC3123 Datasheet

© 2016 Integrated Device Technology, Inc.

5

January 26, 2016

Figure 1.7

Second Order Fit (Typical Part) ...........................................................................................................13

Figure 2.1

ZSSC3123 Block Diagram ...................................................................................................................14

Figure 3.1

General Operation ...............................................................................................................................22

Figure 3.2

Power-On Sequence with Fast Startup Bit Set in EEPROM ...............................................................23

Figure 3.3

Measurement Cycle Timing ................................................................................................................24

Figure 3.4

Measurement Sequence in Update Mode ...........................................................................................25

Figure 3.5

I

2C™ and SPI Data Fetching in Update Mode ....................................................................................27

Figure 3.6

Measurement Sequence in Sleep Mode (Only I

2C™, SPI, or Alarms)................................................28

Figure 3.7

I

2C™ and SPI Data Fetching in Sleep Mode .......................................................................................29

Figure 3.8

I

2C™ Timing Diagram .........................................................................................................................32

Figure 3.9

SPI Timing Diagram.............................................................................................................................33

Figure 3.10 I

2C™ Measurement Packet Reads......................................................................................................34

Figure 3.11 SPI Output Packet with Positive Edge Sampling.................................................................................35

Figure 3.12 I

2C™ MR..............................................................................................................................................36

Figure 3.13 SPI MR.................................................................................................................................................36

Figure 3.14 Example of Alarm Function..................................................................................................................39

Figure 3.15 Alarm Output Flow Chart .....................................................................................................................39

Figure 4.1

I

2C™ Command Format ......................................................................................................................41

Figure 4.2

Command Mode Data Fetch................................................................................................................44

Figure 7.1

Digital Output with Optional Alarms Example......................................................................................54

Figure 7.2

Analog Output with Optional Alarms Example.....................................................................................55

Figure 7.3

Bang-Bang Control System Example ..................................................................................................56

Figure 7.4

Differential Input Capacitance Example ..............................................................................................57

Figure 7.5

Ext. Reference Input Capacitance Example........................................................................................58

Figure 9.1

ZSSC3123 Pin-Out Diagram ...............................................................................................................59

List of Tables

Table 2.1

CDC Multiplier......................................................................................................................................17

Table 2.2

Selection Settings for CREF, and COFF, and Mult (Capacitance ranges are nominal values) ...............18

Table 3.1

CDC Resolution and Conversion Times ..............................................................................................24

Table 3.2

Update Rate Settings ..........................................................................................................................25

Table 3.3

Time Periods between Capacitance Measurements and Temperature Measurements for Different

Mult, Resolution and Update Rates .....................................................................................................26

Table 3.4

Status Table.........................................................................................................................................30

Table 3.5

Diagnostic Detection ............................................................................................................................30

Table 3.6

Normal Operation Diagnostic Table ....................................................................................................30

Table 3.7

Output Modes ......................................................................................................................................31

Table 3.8

Pin Assignment for Output Selections .................................................................................................31