PXD10 Datasheet, PDF (84/130 Pages) Lumins Inc. – 4” Dia.X 6” extruded aluminum step poles

Electrical characteristics
3.9 SSD specifications
3.9.1 Electrical characteristics
Table 36. SSD electrical characteristics
Symbol
C
Parameter
Value¹
Min
Typ
V_VREF
I_VREF
R_IN
V_IN
SSD_CONST
SSD_OFFSET
CC P Reference voltage (I_VREF = 0)
CC P Reference voltage output current
CC D Input resistance (against V_DDM/2)
CC C Input common mode range
CC C SSD constant
CC C SSD offset (unipolar, N_sample =
256)
V_DDM/2 - 0.02
1.85
0.8
V_SSM
0.549
–9
SSD offset (bipolar, N_sample = 256)
–8
SSD offset (bipolar with offset
–5
cancellation, N_sample = 256)
f_SSDSMP CC D SSD cmpout sample rate
0.5
NOTES:
1 _{Vdd = 5.0V +/- 10%, Tj = -40C to +150C.}
V_DDM/2
—
1.0
—
0.572
—
—
—
—
Unit
Max
V_DDM/2 + 0.02 V
—
mA
1.2
M
V_DDM
V
0.597
—
9
counts
8
5
2.0
MHz
3.9.2 Accumulator values
Equation 5 describes the accumulator value in unipolar configuration. The voltage V_in is applied between
the integrator input and V_DDM. The internal generated reference voltage is not connected. The accumulator
value is a function of V_DDM, the number of samples (Nsample) taken and the SSD constant (SSDconst).
The SSD constant and offset (SSDconst, SSDoffset) vary with temperature and process.
ACCval
=
--^V----ⁱ--ⁿ----–-----^--^V----^D-----^D----^M------^---^---2---
VDDM  SSDconst

Nsam
p
le
+
S
S
Dof
f
se
t
Eqn. 5
Equation 6 describes the accumulator value in bipolar configuration. The voltage V_in is applied between
the integrator input and the reference output. The accumulator value depends on the same parameters as
in the unipolar case but the inaccuracy of the voltage reference (Vvref) is compensated.
ACCval
=
---------------------^V---ⁱ--ⁿ---------------------
VDDM  SSDconst

Nsam
p
le
+
S
S
Dof
f
se
t
3.10 RESET electrical characteristics
Eqn. 6
PXD10 Microcontroller Data Sheet, Rev. 1
84
Freescale Semiconductor