SPT5240
DATA SHEET
I
OUT
(mA)
Analog Outputs
The SPT5240 provides differential current outputs which
provide an output level based on the value of R
SET
at
maximum output code (see Figure 3). The required value of
R
SET
may be calculated using the formulas:
LSB = I
FS
/1023
Then:
R
SET
=
1.111 – (1000 • LSB)
4 • LSB
Where I
FS
is the desired full-scale current output.
Each output requires a minimum 5Ω load to analog ground.
The typical circuit utilizes 50Ω loads to develop voltage for
the output transformer (refer to EB5240 data sheet).
Table 1: Input Data Format
Input Code D9 – D0
Analog Output
IO
N
0000000000
1111111111
Sleep XXXXXXXXXX
X indicates either data state.
F
S
0
0
IO
P
0
F
S
0
35
R
SET
Steps = 2.75kΩ
30
25
20
15
10
5
0
60.3
11.2
R
SET
Value (kΩ)
Figure 3: R
SET
vs. I
OUT
Package Dimensions
LQFP-32
A
B
G
H
Symbol
Min
INCHES
Max
MILLIMETERS
Min
Max
C D
I
J
E
F
A
B
C
D
E
F
G
H
I
J
K
L
0.346
0.272
0.346
0.272
0.031
0.012
0.053
0.002
0.037
0°
0.020
0.362
0.280
0.362
0.280
Typ
0.016
0.057
0.006
0.041
0.007
7°
0.030
8.80
9.20
6.90
7.10
8.80
9.20
6.90
7.10
0.80 BSC
0.30
0.40
1.35
1.45
0.05
0.15
0.95
1.05
0.17
0°
7°
0.50
0.75
K
L
REV. 1 June 2003
9