Datasheet

MSP430FG43x
MIXED SIGNAL MICROCONTROLLER
SLAS380C − APRIL 2004 − REVISED MARCH 2011
39
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251−1443
electrical characteristics over recommended operating free-air temperature (unless otherwise
noted) (continued)
12-bit DAC, linearity specifications (see Figure 21)
PARAMETER TEST CONDITIONS V
CC
MIN TYP MAX UNIT
Resolution (12-bit Monotonic) 12 bits
INL
Integral nonlinearity
V
ref
= 1.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2V
±20
±80
LSB
INL
Integral
nonlinearity
(see Note 1)
V
ref
= 2.5 V
DAC12AMPx = 7, DAC12IR = 1
3V
±2.0 ±8.0 LSB
DNL
Differential nonlinearity
V
ref
= 1.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2V
±04
±10
LSB
DNL
Differential
nonlinearity
(see Note 1)
V
ref
= 2.5 V
DAC12AMPx = 7, DAC12IR = 1
3V
±0.4 ±1.0 LSB
Offset voltage w/o
calibration
V
ref
= 1.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2V
±21
E
O
calibration
(see Notes 1, 2)
V
ref
= 2.5 V
DAC12AMPx = 7, DAC12IR = 1
3V
±21
mV
Offset voltage with
calibration
V
ref
= 1.5 V
DAC12AMPx = 7, DAC12IR = 1
2.2V
±25
mV
calibration
(see Notes 1, 2)
V
ref
= 2.5 V
DAC12AMPx = 7, DAC12IR = 1
3V
±2.5
d
E(O)
/d
T
Offset error
temperature coefficient
(see Note 1)
2.2V/3V ±30 μV/C
E
Gain error (see Note 1)
V
REF
= 1.5 V 2.2V
±350
% FSR
E
G
Gain error (see Note 1)
V
REF
= 2.5 V 3V
±3.50 % FSR
d
E(G)
/d
T
Gain temperature
coefficient (see Note 1)
2.2V/3V 10
ppm of
FSR/°C
Time for offset calibration
DAC12AMPx=2 2.2V/3V 100
t
Offset_Cal
Time for offset calibration
(see Note 3)
DAC12AMPx=3,5 2.2V/3V 32
ms
t
Offset
_
Cal
(see Note 3)
DAC12AMPx=4,6,7 2.2V/3V 6
ms
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
effect accuracy and is not recommended.
Positive
Negative
V
R+
Gain Error
Offset Error
DAC Code
DAC V
OUT
Ideal transfer
function
R
Load
=
AV
CC
C
Load
= 100pF
2
DAC Output
Figure 21. Linearity Test Load Conditions and Gain/Offset Definition