ZHCSHX3A December 2014 – March 2018 LDC1312 , LDC1314
PRODUCTION DATA.
- 1 特性
- 2 應(yīng)用
- 3 說明
- 4 修訂歷史記錄
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3 Feature Description
- 7.4 Device Functional Modes
- 7.5 Programming
- 7.6
Register Maps
- 7.6.1 Register List
- 7.6.2 Address 0x00, DATA0
- 7.6.3 Address 0x02, DATA1
- 7.6.4 Address 0x04, DATA2 (LDC1314 only)
- 7.6.5 Address 0x06, DATA3 (LDC1314 only)
- 7.6.6 Address 0x08, RCOUNT0
- 7.6.7 Address 0x09, RCOUNT1
- 7.6.8 Address 0x0A, RCOUNT2 (LDC1314 only)
- 7.6.9 Address 0x0B, RCOUNT3 (LDC1314 only)
- 7.6.10 Address 0x0C, OFFSET0
- 7.6.11 Address 0x0D, OFFSET1
- 7.6.12 Address 0x0E, OFFSET2 (LDC1314 only)
- 7.6.13 Address 0x0F, OFFSET3 (LDC1314 only)
- 7.6.14 Address 0x10, SETTLECOUNT0
- 7.6.15 Address 0x11, SETTLECOUNT1
- 7.6.16 Address 0x12, SETTLECOUNT2 (LDC1314 only)
- 7.6.17 Address 0x13, SETTLECOUNT3 (LDC1314 only)
- 7.6.18 Address 0x14, CLOCK_DIVIDERS0
- 7.6.19 Address 0x15, CLOCK_DIVIDERS1
- 7.6.20 Address 0x16, CLOCK_DIVIDERS2 (LDC1314 only)
- 7.6.21 Address 0x17, CLOCK_DIVIDERS3 (LDC1314 only)
- 7.6.22 Address 0x18, STATUS
- 7.6.23 Address 0x19, ERROR_CONFIG
- 7.6.24 Address 0x1A, CONFIG
- 7.6.25 Address 0x1B, MUX_CONFIG
- 7.6.26 Address 0x1C, RESET_DEV
- 7.6.27 Address 0x1E, DRIVE_CURRENT0
- 7.6.28 Address 0x1F, DRIVE_CURRENT1
- 7.6.29 Address 0x20, DRIVE_CURRENT2 (LDC1314 only)
- 7.6.30 Address 0x21, DRIVE_CURRENT3 (LDC1314 only)
- 7.6.31 Address 0x7E, MANUFACTURER_ID
- 7.6.32 Address 0x7F, DEVICE_ID
-
8 Application and Implementation
- 8.1
Application Information
- 8.1.1 Conductive Objects in a Time-Varying EM Field
- 8.1.2 L-C Resonators
- 8.1.3 Multi-Channel and Single Channel Operation
- 8.1.4 Sensor Conversion Time
- 8.1.5 Sensor Current Drive Configuration
- 8.1.6 Clocking Architecture
- 8.1.7 Input Deglitch Filter
- 8.1.8 Device Status Registers
- 8.1.9 Multi-Channel Data Readback
- 8.2 Typical Application
- 8.1
Application Information
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機械、封裝和可訂購信息
封裝選項
機械數(shù)據(jù) (封裝 | 引腳)
- DNT|12
散熱焊盤機械數(shù)據(jù) (封裝 | 引腳)
訂購信息
8.1.3 Multi-Channel and Single Channel Operation
The multi-channel package of the LDC enables the user to save board space and support flexible system design. For example, temperature drift can often cause a shift in component values, resulting in a shift in resonant frequency of the sensor. Using a second sensor as a reference or in a differential configuration provides the capability to cancel out temperature shifts and other environmental variations. When operated in multi-channel mode, the LDC sequentially samples the selected channels - only one channel is active at any time while the other selected channels are held in an inactive state. In single channel mode, the LDC samples a single channel, which is selectable. Refer to Inactive Channel Sensor Connections for more details on inactive channels.
Inactive channels have the corresponding INAx and INBx pins tied to ground. The following table shows the registers and values that are used to configure either multi-channel or single channel modes.
Figure 49. Multi-Channel Mode Sequencing
Figure 50. Single-Channel Mode Sequencing
Table 32. Single and Multi-Channel Configuration Registers
| MODE | REGISTER | FIELD | VALUE(1) |
|---|---|---|---|
| Single channel | CONFIG, addr 0x1A | ACTIVE_CHAN [15:14] | 00 = chan 0 |
| 01 = chan 1 | |||
| 10 = chan 2 | |||
| 11 = chan 3 | |||
| MUX_CONFIG addr 0x1B | AUTOSCAN_EN [15] | 0 = continuous conversion on a single channel (default) | |
| Multi-channel | MUX_CONFIG addr 0x1B | AUTOSCAN_EN [15] | 1 = continuous conversion on multiple channels |
| MUX_CONFIG addr 0x1B | RR_SEQUENCE [14:13] | 00 = Ch0, Ch 1 | |
| 01 = Ch0, Ch 1, Ch 2 | |||
| 10 = Ch0, CH1, Ch2, Ch3 |
The digitized sensor measurement for each channel (DATAx) represents the ratio of the sensor frequency to the reference frequency. The data outputs represent the 12 MSBs of a 16-bit result. With the FIN_DIVIDER set to 1 and OFFSET set to 0, the sensor frequency can be calculated from:
The following table illustrates the registers that contain the fixed point sample values for each channel.
Table 33. LDC1314/1312 Sample Data Registers
| CHANNEL(1) | REGISTER | FIELD NAME [BITS(S) ] | VALUE |
|---|---|---|---|
| 0 | DATA0, addr 0x00 | DATA0 [11:0] | 12 bit conversion results
0x000 = sensor under range condition 0xfff = sensor over range condition |
| 1 | DATA1, addr 0x02 | DATA1 [11:0] | 12 bit conversion results.
0x000 = sensor under range condition 0xfff = sensor over range condition |
| 2 | DATA2, addr 0x04 | DATA2 [11:0] | 12 bit conversion result.
0x000 = sensor under range condition 0xfff = sensor over range condition |
| 3 | DATA3, addr 0x06 | DATA3 [11:0] | 12 bit conversion result.
0x000 = sensor under range condition 0xfff = sensor over range condition |