ZHCSHX3A December 2014 – March 2018 LDC1312 , LDC1314
PRODUCTION DATA.
- 1 特性
- 2 應用
- 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
8.1.4.1 Settling Time
When the LDC sequences through the channels in multi-channel mode, the dwell time interval for each channel is the sum of 3 parts: sensor activation time + conversion time + channel switch delay.
The sensor activation time is the amount of settling time required for the sensor oscillation amplitude to stabilize, as shown in Figure 49. The settling wait time is programmable and should be set to a value that is long enough to allow stable oscillation. The settling wait time for channel x is given by:
Table 37 illustrates the registers and values for configuring the settling time for each channel.
Table 37. Settling Time Register Configuration
| CHANNEL(1) | REGISTER | FIELD | CONVERSION TIME(2) |
|---|---|---|---|
| 0 | SETTLECOUNT0, addr 0x10 | SETTLECOUNT0 ['15:0] | (SETTLECOUNT0×16)/fREF0 |
| 1 | SETTLECOUNT1, addr 0x11 | SETTLECOUNT1 [15:0] | (SETTLECOUNT1×16)/fREF1 |
| 2 | SETTLECOUNT2, addr 0x12 | SETTLECOUNT2 [15:0] | (SETTLECOUNT2×16)/fREF2 |
| 3 | SETTLECOUNT3, addr 0x13 | SETTLECOUNT3 [15:0] | (SETTLECOUNT3×16)/fREF3 |
The SETTLECOUNTx for any channel x must satisfy:
where
- ƒSENSORx = Sensor Frequency of Channel x
- ƒREFx = Reference frequency for Channel x
- QSENSORx = Quality factor of the sensor on Channel x. The sensor Q can be calculated with:
Round the result to the next highest integer (for example, if Equation 10 recommends a minimum value of 6.08, program the register to 7 or higher).
L, RP and C values can be obtained by using Texas Instrument’s WEBENCH® for the coil design.