13/15

ACHIEVING HIGH ACCURACY AND 13-BIT RESOLUTION WITH ST7LITE2 ADC

Table 5 ADC Analysis (Before and After FILTER)

Where:

OFFSET CNT = 58 in LSB (AMPCAL=1)

ADC output in LSB (Offset Compensated) = ADC output in LSB (ADCDRH + ADCDRL) -

OFFSET CNT

5 CONCLUSION

Overall, the ST7LITE2 ADC + Amplifier is a good price/performance trade-off with effective

resolution of 13-bit, which can be used in various applications where small signal amplification

is required with minimum hardware interface.

noise to a minimum for which you can use different techniques explained above. With these

techniques we are able to restrict the ADC error within ±3 LSB at room temperature with am-

plifier ON.

An important thing to remember while using the ST7LITE2 amplifier is the “offset compensa-

tion”, which is mandatory due to the design of the device.

in mV

Ideal ADC

CNT in

LSB

ADC output in LSB

ADCDRH + ADCDRL

ADC output in LSB (Off-

set Compensated)

Max

Min

Max

Min

50

82

145

136

87

78

200

328

393

383

335

325

400

656

718

710

660

652

ADC Output with H/W and S/W filtering (in LSB)

50

82

141

140

83

82

200

328

388

383

330

325

400

656

716

714

658

656