Adc - SimCom SIM5215 Hardware Design

：
Note 50ms<t<200ms. ESD components are suggested to be used on Reset pin.

3.12.2 ADC

SIM5215&SIM5216 has a dedicated ADC that is available for digitizing analog signals such as battery
voltage and so on; it is on PIN 41, namely HKADC. This HKADC is 8 bit successive-approximation
circuit, and electronic specification is shown in the following table.
Table 32: Electronic Characteristics
Specification
Resolution
Differential nonlinearity
Integral nonlinearity
Gain Error
Offset Error
Input Range
Input serial resistance
Input capacitance
Power-down to wakeup
User can introduce a signal in the ADC pin directly and use the AT command "AT+CADC" to get the raw
data which is between 0 and 4095. The data can be transformed to any type such as voltage, temperature
etc. Please refer to document [1].
SIM5215&SIM5216_Hardware Design_V2.02
Figure 40: Reset circuit
Min Typ Max
12
-4 +4
-8 +8
-2.5 +2.5
-4 +40
GND 2.2V
2
53
9.6 19.2
Figure 41: Reference circuit
Smart Machine Smart Decision
Unit Comments/Conditions
Bits
LSB
LSB
Analog Vdd = ADC reference
2.4MHz sample rate
%
LSB
V
kΩ Sample and hold switch resistance
pF
μs
51
2012-08-31