 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
MCP3421 Datasheet(PDF) 14 Page - Microchip Technology |
|
|
|||||||||||||||||||||||||||||
MCP3421 Datasheet(HTML) 14 Page - Microchip Technology |
|
|
14 / 42 page  MCP3421 DS22003E-page 14 © 2009 Microchip Technology Inc. 4.9.2 CONVERTING THE DEVICE OUTPUT CODE TO INPUT SIGNAL VOLTAGE When the user gets the digital output codes from the device as described in Section 4.9.1 “Digital output code from device”, the next step is converting the digital output codes to a measured input voltage. Equation 4-4 shows an example of converting the output codes to its corresponding input voltage. If the sign indicator bit (MSB) is ‘0’, the input voltage is obtained by multiplying the output code with the LSB and divided by the PGA setting. If the sign indicator bit (MSB) is ‘1’, the output code needs to be converted to two’s complement before multiplied by LSB and divided by the PGA setting. Table 4-4 shows an example of converting the device output codes to input voltage. EQUATION 4-4: CONVERTING OUTPUT CODES TO INPUT VOLTAGE TABLE 4-4: EXAMPLE OF CONVERTING OUTPUT CODE TO VOLTAGE (WITH 18 BIT SETTING) If MSB = 0 (Positive Output Code): If MSB = 1 (Negative Output Code): Where: LSB = See Table 4-1 2’s complement = 1’s complement + 1 Input Voltage (Output Code) LSB PGA ------------ • = Input Voltage (2 ′s complement of Output Code) LSB PGA ------------ • = Input Voltage [VIN+-VIN-] • PGA] Digital Output Code MSB (sign bit) Example of Converting Output Codes to Input Voltage ≥ V REF 011111111111111111 0 (2 16+215+214+213+212+211+210+29+28+27+26+25+24+23+22+ 2 1+20)x LSB(15.625 μV)/PGA = 2.048 (V) for PGA = 1 VREF - 1 LSB 011111111111111111 0 (2 16+215+214+213+212+211+210+29+28+27+26+25+24+23+22+ 2 1+20)x LSB(15.625 μV)/PGA = 2.048 (V) for PGA = 1 2LSB 000000000000000010 0 (0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+2 1+0)x LSB(15.625 μV)/PGA = 31.25 (μV) for PGA = 1 1LSB 000000000000000001 0 (0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+2 0)x LSB(15.625 μV)/PGA = 15.625 (μV)for PGA = 1 0 000000000000000000 0 (0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0)x LSB(15.625 μV)/PGA = 0 V (V) for PGA = 1 -1 LSB 111111111111111111 1 -(0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+2 0)x LSB(15.625 μV)/PGA = - 15.625 (μV)for PGA = 1 -2 LSB 111111111111111110 1 -(0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+2 1+0)x LSB(15.625 μV)/PGA = - 31.25 (μV)for PGA = 1 - VREF 100000000000000000 1 -(2 17+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0) x LSB(15.625 μV)/PGA = - 2.048 (V) for PGA = 1 ≤ -V REF 100000000000000000 1 -(2 17+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0+0) x LSB(15.625 μV)/PGA = - 2.048 (V) for PGA = 1 |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
