MSP430FR573X Datasheet, PDF (65/109 Pages) Texas Instruments – MIXED SIGNAL MICROCONTROLLER

MSP430FR573x
MSP430FR572x
www.ti.com
SLAS639D – JULY 2011 – REVISED AUGUST 2012
REF, External Reference
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) ⁽¹⁾
V_eREF+
V_eREF–
(V_eREF+ –
V_REF–/V_eREF–)
I_VeREF+,
I_VeREF–
PARAMETER
Positive external reference voltage input
Negative external reference voltage input
Differential external reference voltage
input
Static input current
TEST CONDITIONS
V_eREF+ > V_eREF– ⁽²⁾
V_eREF+ > V_eREF– ⁽³⁾
V_eREF+ > V_eREF– ⁽⁴⁾
1.4 V ≤ V_eREF+ ≤ V_AVCC,
V_eREF– = 0 V,
f_ADC10CLK = 5 MHz,
ADC10SHTx = 1h,
Conversion rate 200 ksps
1.4 V ≤ V_eREF+ ≤ V_AVCC,
V_eREF– = 0 V,
f_ADC10CLK = 5 MHz,
ADC10SHTx = 8h,
Conversion rate 20 ksps
V_CC
MIN TYP
1.4
0
1.4
2.2 V, 3 V
-6
2.2 V, 3 V
-1
C_VREF+, C_VREF-
Capacitance at VREF+ or VREF- terminal
(5)
10
MAX
AV_CC
1.2
UNIT
V
V
AV_CC V
6 µA
1 µA
µF
(1) The external reference is used during ADC conversion to charge and discharge the capacitance array. The input capacitance, C_i, is also
the dynamic load for an external reference during conversion. The dynamic impedance of the reference supply should follow the
recommendations on analog-source impedance to allow the charge to settle for 12-bit accuracy.
(2) The accuracy limits the minimum positive external reference voltage. Lower reference voltage levels may be applied with reduced
accuracy requirements.
(3) The accuracy limits the maximum negative external reference voltage. Higher reference voltage levels may be applied with reduced
accuracy requirements.
(4) The accuracy limits minimum external differential reference voltage. Lower differential reference voltage levels may be applied with
reduced accuracy requirements.
(5) Two decoupling capacitors, 10 µF and 100 nF, should be connected to VREF to decouple the dynamic current required for an external
reference source if it is used for the ADC10_B. Also see the MSP430FR57xx Family User's Guide (SLAU272).
REF, Built-In Reference
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)
V_REF+
PARAMETER
Positive built-in reference
voltage output
TEST CONDITIONS
REFVSEL = {2} for 2.5 V, REFON = 1
REFVSEL = {1} for 2 V, REFON = 1
REFVSEL = {0} for 1.5 V, REFON = 1
V_CC
MIN TYP
3V
2.4 2.5
3V
1.92 2.0
3V
1.44 1.5
AV_CC minimum voltage,
REFVSEL = {0} for 1.5 V
2.0
AV_CC(min) Positive built-in reference
REFVSEL = {1} for 2 V
2.2
active
REFVSEL = {2} for 2.5 V
2.7
I_REF+
Operating supply current into f_ADC10CLK = 5 MHz,
AVCC terminal ⁽¹⁾
REFON = 1, REFBURST = 0
3V
33
T_REF+
Temperature coefficient of
built-in reference
REFVSEL = (0, 1, 2}, REFON = 1
±35
AV_CC = AV_{CC (min)} - AV_CC(max),
T_A = 25°C, REFON = 1,
REFVSEL = (0} for 1.5 V
1600
PSRR_DC
Power supply rejection ratio
(DC)
AV_CC = AV_{CC (min)} - AV_CC(max),
T_A = 25°C, REFON = 1,
REFVSEL = (1} for 2 V
1900
AV_CC = AV_{CC (min)} - AV_CC(max),
T_A = 25°C, REFON = 1,
REFVSEL = (2} for 2.5 V
3600
t_SETTLE
Settling time of reference
voltage ⁽²⁾
AV_CC = AV_{CC (min)} - AV_CC(max),
REFVSEL = (0, 1, 2}, REFON = 0 → 1
30
MAX
2.6
2.08
1.56
UNIT
V
V
45 µA
ppm/
°C
µV/V
µs
(1) The internal reference current is supplied by terminal AVCC. Consumption is independent of the ADC10ON control bit, unless a
conversion is active. The REFON bit enables to settle the built-in reference before starting an A/D conversion.
(2) The condition is that the error in a conversion started after t_REFON is less than ±0.5 LSB.
Copyright © 2011–2012, Texas Instruments Incorporated
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