el5223 Intersil Corporation, el5223 Datasheet - Page 12

• Manufacturer Part Number: el5223
• Description: 12mhz 4-, 8-, 10- And 12-channel Rail-to-rail Input-output Buffers
• Manufacturer: Intersil Corporation

Applications Information
Product Description
The EL5123, EL5223, EL5323, and EL5423 unity gain
buffers are fabricated using a high voltage CMOS process. It
exhibits rail-to-rail input and output capability and has low
power consumption (600µA per buffer). These features
make the EL5123, EL5223, EL5323, and EL5423 ideal for a
wide range of general-purpose applications. When driving a
load of 10kΩ and 12pF, the EL5123, EL5223, EL5323, and
EL5423 have a -3dB bandwidth of 12MHz and exhibits
15V/µs slew rate.
Operating Voltage, Input, and Output
The EL5123, EL5223, EL5323, and EL5423 are specified
with a single nominal supply voltage from 5V to 15V or a split
supply with its total range from 5V to 15V. Correct operation
is guaranteed for a supply range of 4.5V to 16.5V. Most
EL5123, EL5223, EL5323, and EL5423 specifications are
stable over both the full supply range and operating
temperatures of -40°C to +85°C. Parameter variations with
operating voltage and/or temperature are shown in the
typical performance curves.
The output swings of the EL5123, EL5223, EL5323, and
EL5423 typically extend to within 50mV of positive and
negative supply rails with load currents of 5mA. Decreasing
load currents will extend the output voltage range even
closer to the supply rails. Figure 24 shows the input and
output waveforms for the device. Operation is from ±5V
supply with a 10kΩ load connected to GND. The input is a
10V
9.985V
Short Circuit Current Limit
The EL5123, EL5223, EL5323, and EL5423 will limit the
short circuit current to ±120mA if the output is directly
shorted to the positive or the negative supply. If an output is
shorted indefinitely, the power dissipation could easily
increase such that the device may be damaged. Maximum
reliability is maintained if the output continuous current never
FIGURE 24. OPERATION WITH RAIL-TO-RAIL INPUT AND
P-P
P-P
sinusoid. The output voltage is approximately
.
5V
5V
OUTPUT
12
10µs
V
T
V
A
S
IN
EL5123, EL5223, EL5323, EL5423
=±5V
=25°C
=10V
P-P
exceeds ±30mA. This limit is set by the design of the internal
metal interconnects.
Output Phase Reversal
The EL5123, EL5223, EL5323, and EL5423 are immune to
phase reversal as long as the input voltage is limited from
V
output of the device with the input voltage driven beyond the
supply rails. Although the device's output will not change
phase, the input's over-voltage should be avoided. If an input
voltage exceeds supply voltage by more than 0.6V,
electrostatic protection diodes placed in the input stage of
the device begin to conduct and over-voltage damage could
occur.
Power Dissipation
With the high-output drive capability of the EL5123, EL5223,
EL5323, and EL5423 buffer, it is possible to exceed the
125°C “absolute-maximum junction temperature” under
certain load current conditions. Therefore, it is important to
calculate the maximum junction temperature for the
application to determine if load conditions need to be
modified for the buffer to remain in the safe operating area.
The maximum power dissipation allowed in a package is
determined according to:
P
where:
The maximum power dissipation actually produced by an IC
is the total quiescent supply current times the total power
supply voltage, plus the power in the IC due to the loads, or:
P
S
DMAX
DMAX
FIGURE 25. OPERATION WITH BEYOND-THE-RAILS INPUT
T
T
θ
P
- -0.5V to V
JA
JMAX
AMAX
DMAX
= Thermal resistance of the package
=
=
= Maximum junction temperature
= Maximum ambient temperature
T
-------------------------------------------- -
Σi V
= Maximum power dissipation in the package
JMAX
[
1V
1V
S
S
d
+ +0.5V. Figure 25 shows a photo of the
×
Θ
–
I
JA
SMAX
T
AMAX
+
(
V
S
+
–
10µs
V
OUT
i )
×
V
T
V
I
A
S
IN
LOAD
=±2.5V
=25°C
=6V
P-P
i ]
May 3, 2007
FN7176.2