el5244 Intersil Corporation, el5244 Datasheet - Page 15

• Manufacturer Part Number: el5244
• Description: 100mhz Single-supply Rail-to-rail Amplifiers
• Manufacturer: Intersil Corporation

Pin Descriptions
Description of Operation and Applications
Information
Product Description
The EL5144 series is a family of wide bandwidth, single
supply, low power, rail-to-rail output, voltage feedback
operational amplifiers. The family includes single, dual, and
quad configurations. The singles and duals are available with
a power down pin to reduce power to 2.6µA typically. All the
amplifiers are internally compensated for closed loop
feedback gains of +1 or greater. Larger gains are acceptable
but bandwidth will be reduced according to the familiar Gain-
Bandwidth Product.
Connected in voltage follower mode and driving a high
impedance load, the EL5144 series has a -3dB bandwidth of
100MHz. Driving a 150Ω load, they have a -3dB bandwidth
of 60MHz while maintaining a 200V/µs slew rate. The input
common mode voltage range includes ground while the
output can swing rail to rail.
Power Supply Bypassing and Printed Circuit
Board Layout
As with any high-frequency device, good printed circuit
board layout is necessary for optimum performance. Ground
plane construction is highly recommended. Lead lengths
should be as short as possible. The power supply pin must
be well bypassed to reduce the risk of oscillation For normal
single supply operation, where the GND pin is connected to
the ground plane, a single 4.7µF tantalum capacitor in
parallel with a 0.1µF ceramic capacitor from V
SOT23
5-PIN
SO/PDIP
8-PIN
1,5
8
SO/PDIP/
MSOP
8-PIN
(Continued)
15
16-PIN
MSOP
2
4
EL5144, EL5146, EL5244, EL5246, EL5444
SO/PDIP
14-PIN
10,12
2,6,
3
5
S
to GND will
SO/PDIP
14-PIN
14
16-PIN
QSOP
16
suffice. This same capacitor combination should be placed
at each supply pin to ground if split supplies are to be used.
In this case, the GND pin becomes the negative supply rail.
For good AC performance, parasitic capacitance should be
kept to a minimum. Use of wire wound resistors should be
avoided because of their additional series inductance. Use of
sockets, particularly for the SO package, should be avoided
if possible. Sockets add parasitic inductance and
capacitance that can result in compromised performance.
Input, Output, and Supply Voltage Range
The EL5144 series has been designed to operate with a
single supply voltage of 5V. Split supplies can be used so
long as their total range is 5V.
The amplifiers have an input common mode voltage range
that includes the negative supply (GND pin) and extends to
within 1.5V of the positive supply (V
specified over this range.
The output of the EL5144 series amplifiers can swing rail to
rail. As the load resistance becomes lower in value, the
ability to drive close to each rail is reduced. However, even
with an effective 150Ω load resistor connected to a voltage
halfway between the supply rails, the output will swing to
within 150mV of either rail.
NAME
OUTD
CEA
CEB
NC
CE
Amplifier D
Output
Enable (Enabled
when high)
Enable Amplifier
A (Enabled
when high)
Enable Amplifier
B (Enabled
when high)
No Connect. Not
internally
connected.
FUNCTION
(Reference Circuit 2)
Circuit 3
(Reference Circuit 3)
(Reference Circuit 3)
EQUIVALENT CIRCUIT
S
pin). They are
GND
V
S
+
–
1.4V