Texas Instruments CC430F5133, Manual

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ECCN 5E002 TSPA - Technology / Software Publicly Available
CC430F6137, CC430F6135, CC430F6127, CC430F6126, CC430F6125
CC430F5137, CC430F5135, CC430F5133
www.ti.com SLAS554H – MAY 2009 – REVISED SEPTEMBER 2013
REF, External Reference
over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)
(1)
PARAMETER TEST CONDITIONS V
CC
MIN TYP MAX UNIT
V
eREF+
Positive external reference voltage input V
eREF+
> V
REF–
/V
eREF–
(2)
1.4 AV
CC
V
V
REF–
/V
eREF–
Negative external reference voltage input V
eREF+
> V
REF–
/V
eREF–
(3)
0 1.2 V
(V
eREF+
– Differential external reference voltage
V
eREF+
> V
REF–
/V
eREF–
(4)
1.4 AV
CC
V
V
REF–
/V
eREF–
) input
1.4 V ≤ V
eREF+
≤ V
AVCC
,
V
eREF–
= 0 V
f
ADC12CLK
= 5 2.2 V, 3 V ±8.5 ±26 µA
MHz,ADC12SHTx = 1h,
Conversion rate 200ksps
I
VeREF+
Static input current
I
VREF–/VeREF–
1.4 V ≤ V
eREF+
≤ V
AVCC
,
V
eREF–
= 0 V
f
ADC12CLK
= 5 2.2 V, 3 V ±1 µA
MHz,ADC12SHTx = 8h,
Conversion rate 20ksps
Capacitance at VREF+ or VREF- terminal,
C
VREF+/-
10 µF
external reference
(5)
(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 ADC12_A. See also the
CC430 Family User's Guide ( SLAU259 ).
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