MSP430X241X Datasheet, PDF (69/98 Pages) Texas Instruments – MIXED SIGNAL MICROCONTROLLER

MSP430x241x, MSP430x261x
MIXED SIGNAL MICROCONTROLLER
SLAS541A -- JUNE 2007 -- REVISED OCTOBER 2007
electrical characteristics over recommended operating free-air temperature (unless otherwise
noted) (continued)
12-bit DAC linearity specifications (see Figure 41)
PARAMETER
TEST CONDITIONS
VCC
MIN TYP MAX UNIT
Resolution
12-bit monotonic
12
bits
V_REF = 1.5 V
DAC12AMPx = 7, DAC12IR = 1
INL
Integral nonlinearity (see Note 1)
V_REF = 2.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2 V
3V
±2.0 ±8.0 LSB
DNL
Differential nonlinearity
(see Note 1)
V_REF = 1.5 V
DAC12AMPx = 7, DAC12IR = 1
V_REF = 2.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2 V
3V
±0.4 ±1.0 LSB
V_REF = 1.5 V
Offset voltage without calibration ^{DAC12AMPx = 7, DAC12IR = 1}
(see Notes 1 and 2)
V_REF = 2.5 V
E_O
DAC12AMPx = 7, DAC12IR = 1
V_REF = 1.5 V
Offset voltage with calibration
DAC12AMPx = 7, DAC12IR = 1
(see Notes 1 and 2)
V_REF = 2.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2 V
3V
2.2 V
3V
±21
mV
±2.5
d_E(O)/d_T
Offset error temperature
coefficient (see Note 1)
2.2 V/3 V
30
μV/C
E_G
d_E(G)/d_T
Gain error (see Note 1)
Gain temperature
coefficient (see Note 1)
V_REF = 1.5 V
V_REF = 2.5 V
2.2 V
3V
2.2 V/3 V
±3.50 % FSR
10
ppm of
FSR/°C
t_{Offset_Cal}
Time for offset calibration
(see Note 3)
DAC12AMPx = 2
DAC12AMPx = 3, 5
DAC12AMPx = 4, 6, 7
2.2 V/3 V
100
32 ms
6
NOTES:
1. Parameters calculated from the best-fit curve from 0x0A to 0xFFF. The best-fit curve method is used to deliver coefficients “a” and
“b” of the first order equation: y = a + b × x. V_{DAC12_xOUT} = E_O + (1 + E_G) × (V_eREF+/4095) × DAC12_xDAT, DAC12IR = 1.
2. The offset calibration works on the output operational amplifier. Offset calibration is triggered setting bit DAC12CALON.
3. The offset calibration can be done if DAC12AMPx = {2, 3, 4, 5, 6, 7}. The output operational amplifier is switched off with
DAC12AMPx = {0, 1}. It is recommended that the DAC12 module be configured prior to initiating calibration. Port activity during
calibration may affect accuracy and is not recommended.
DAC Output
RLoad =
AV _CC
2
CLoad = 100pF
DAC VOUT
VR+
Ideal transfer
function
Offset Error
Positive
Negative
Gain Error
DAC Code
Figure 41. Linearity Test Load Conditions and Gain/Offset Definition
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