Datasheet

LM12454, LM12458, LM12H458
www.ti.com SNAS079A –MAY 2004–REVISED FEBRUARY 2006
DC CHARACTERISTICS
(1) (2) (3)
The following specifications apply to the LM12454, LM12458, and LM12H458 for V
A
+ = V
D
+ = 5V, V
REF+
= 5V, V
REF−
= 0V,
f
CLK
= 8.0 MHz (LM12H454/8) or f
CLK
= 5.0 MHz (LM12458), and minimum acquisition time unless otherwise specified.
Boldface limits apply for T
A
= T
J
= T
MIN
to T
MAX
; all other limits T
A
= T
J
= 25°C.
Symbol Parameter Conditions Typical
(4)
Limits
(5)
Units
CS = “1”
I
D
+ V
D
+ Supply Current LM12454/8 0.55 1.0 mA (max)
LM12H458 0.55 1.2 mA (max)
CS = “1”
I
A
+ V
A
+ Supply Current LM12454/8 3.1 5.0 mA (max)
LM12H458 3.1 5.5 mA (max)
Stand-By Supply Current (I
D
+) + (I
A
+) Clock Stopped 10 μA (max)
I
ST
[Power-Down Mode Selected] 8 MHz Clock 40 μA (max)
V
A
+ = 5.5V
ON-Channel = 5.5V, 0.1 0.3 μA (max)
Multiplexer ON-Channel Leakage
OFF-Channel = 0V
Current
ON-Channel = 0V
0.1 0.3 μA (max)
OFF-Channel = 5.5V
V
A
+ = 5.5V
ON-Channel = 5.5V 0.1 0.3 μA (max)
Multiplexer OFF-Channel Leakage
OFF-Channel = 0V
Current
ON-Channel = 0V 0.3
0.1 μA (max)
OFF-Channel = 5.5V
LM12454
V
IN
= 5V 800 1500 Ω(max)
R
ON
Multiplexer ON-Resistance
V
IN
= 2.5V 850 1500 Ω(max)
V
IN
= 0V 760 1500 Ω(max)
LM12454
V
IN
= 5V ±1.0% ±3.0% (max)
Multiplexer Channel-to-Channel
R
ON
matching
V
IN
= 2.5V ±1.0% ±3.0% (max)
V
IN
= 0V ±1.0% ±3.0% (max)
(1) Two on-chip diodes are tied to each analog input through a series resistor, as shown below. Input voltage magnitude up to 5V above
V
A
+ or 5V below GND will not damage the LM12454 or the LM12(H)458. However, errors in the A/D conversion can occur if these
diodes are forward biased by more than 100 mV. As an example, if V
A
+ is 4.5 V
DC
, full-scale input voltage must be ≤4.6 V
DC
to ensure
accurate conversions. See Figure 3
(2) V
A
+ and V
D
+ must be connected together to the same power supply voltage and bypassed with separate capacitors at each V
+
pin to
assure conversion/comparison accuracy.
(3) Accuracy is ensured when operating at f
CLK
= 5 MHz for the LM12454/8 and f
CLK
= 8 MHz for the LM12H458.
(4) Typical figures are at T
A
= 25°C and represent most likely parametric norm.
(5) Limits are to AOQL (Average Output Quality Level).
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Product Folder Links: LM12454 LM12458 LM12H458