Datasheet

MSP430x461x1, MSP430x461x
MIXED SIGNAL MICROCONTROLLER
52
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics over recommended operating free-air temperature (unless otherwise
noted) (continued)
12-bit ADC, built-in reference
PARAMETER TEST CONDITIONS V
CC
MIN TYP MAX UNIT
V
Positive built-in
reference voltage
REF2_5V = 1 for 2.5 V,
I
VREF+
max ≤ I
VREF+
≤ I
VREF+
min
3 V 2.4 2.5 2.6
V
V
REF+
reference voltage
output
REF2_5V = 0 for 1.5 V,
I
VREF+
max ≤ I
VREF+
≤ I
VREF+
min
2.2 V/3 V 1.44 1.5 1.56
V
AV
AV
CC
minimum
voltage, Positive
REF2_5V = 0, I
VREF+
max ≤ I
VREF+
≤ I
VREF+
min
2.2
V
AV
CC(min)
voltage
,
Positive
built-in reference
REF2_5V = 1, I
VREF+
min ≥ I
VREF+
≥ −0.5mA 2.8
V
built in
reference
active
REF2_5V = 1, I
VREF+
min ≥ I
VREF+
≥ −1mA 2.9
I
Load current out of
2.2 V 0.01 −0.5
mA
I
VREF+
Load
current
out
of
V
REF+
terminal
3 V 0.01 −1
mA
I
VREF+
= 500 µA +/− 100 µA,
Analog input voltage 0 75 V;
2.2 V ±2
LSB
I
Load-current
regulation V
Analog input voltage ~0.75 V;
REF2_5V = 0
3 V ±2
LSB
I
L(VREF)+
regulation V
REF+
terminal
I
VREF+
= 500 µA ± 100 µA,
Analog input voltage ~1.25 V,
REF2_5V = 1
3 V ±2 LSB
I
Load current
regulation V
I
VREF+
=100 µA → 900 µA,
C 5 µF ax 05xV
3V
20
ns
I
DL(VREF) +
regulation V
REF+
terminal
C
VREF+
=5 µF, ax ~0.5 x V
REF+
,
Error of conversion result ≤ 1 LSB
3 V 20 ns
C
VREF+
Capacitance at pin
V
REF+
(see Note 1)
REFON =1,
0 mA ≤ I
VREF+
≤ I
VREF+
max
2.2 V/3 V 5 10 µF
T
REF+
Temperature
coefficient of built-in
reference
I
VREF+
is a constant in the range of
0 mA ≤ I
VREF+
≤ 1 mA
2.2 V/3 V ±100 ppm/°C
t
REFON
Settle time of internal
reference voltage
(see Figure 23 and
Note 2)
I
VREF+
= 0.5 mA, C
VREF+
= 10 µF,
V
REF+
= 1.5 V, V
AVCC
= 2.2 V
17 ms
NOTES: 1. The internal buffer operational amplifier and the accuracy specifications require an external capacitor. All INL and DNL tests uses
two capacitors between pins V
REF+
and AV
SS
and V
REF−
/V
eREF−
and AV
SS
: 10 µF tantalum and 100 nF ceramic.
2. The condition is that the error in a conversion started after t
REFON
is less than ±0.5 LSB. The settling time depends on the external
capacitive load.