NE5537 Philipss, NE5537 Datasheet - Page 8

• Manufacturer Part Number: NE5537
• Description: Sample-and-hold amplifier
• Manufacturer: Philipss

Philips Semiconductors Linear Products
A curve labeled “Aperture Time” has been included for sampling
conditions where the input is steady during the sampling period, but
may experience a sudden change nearly coincident with the “HOLD”
command. This curve is based on a 1mV error fed into the output.
A second curve, “Hold Settling Time,” indicates the time required for
the output to settle to 1mV after the “HOLD” command.
Digital Feedthrough
Fast rise time logic signals can cause hold errors by feeding
externally into the analog input at the same time the amplifier is put
into the hold mode. To minimize this problem, board layout should
keep logic lines as far as possible from the analog input. Grounded
guarding traces may also be used around the input line, especially if
it is driven from a high impedance source. Reducing high amplitude
logic signals to 2.5V will also help.
Logic signals also couple to the hold capacitor. This hold capacitor
should be guarded by a PC card trace connected to the
sample-and-hold output. This will also minimize board leakage.
August 31, 1994
Sample-and-hold amplifier
V
NOTE:
OUT
V IN x
256
1
(20 D 0
V
2 1 D 1
ANALOG INPUT 1
ANALOG INPUT 2
ANALOG INPUT 3
ANALOG INPUT 4
IN
CONTROL 1
CONTROL 2
CONTROL 3
CONTROL 4
2 7 D 7 ) Equation 1
NE5537
Figure 2. Multiplying DAC Application
SD5000
SUBSTRATE
Figure 3. Analog Data Multiplexing
5k
+VREF
5008/DAC-08
891
D0-D7
IN
SPECIAL NOTES
1. Not all definitions herein defined are measured parametrically for
2. Reference should be made to Design Engineering, Volumes 23
3. Reference also made to National Semiconductor Corporation’s
NE5537
the NE5537, but are legitimate terms used in sample-and-hold
systems.
(Nov. 8, 1978), 25 (Dec. 6, 1978) and 26 (Dec. 20, 1978) for
articles written by Eugene Zuch of Datel Systems, Inc., for a
further discussion of sample-and-hold circuits.
Special Functions Data Book (1976).
SUCCESSIVE APPROXIMATION
(NE5034, NE5037)
or INTEGRATING TYPE ADC
CONVERTER
530
A/D
5k
D
D
V
0
7
OUT
NE/SE5537
Product specification