monolithic sample/hold amplifiers featuring high DC
accuracy with fast acquisition times and a low droop
rate. Dynamic performance and holding performance
can be optimized with proper selection of the external
holding capacitor. With a 1000pF holding capacitor,
12-bit accuracy can be achieved with a 6µs acquisition
time. Droop rates less than 5mV/min are possible with
a 1µF holding capacitor.
These sample/holds will operate over a wide supply
voltage ranging from
±5V
to
±18V
with very little
change in performance. A separate Offset Adjust pin
is used to adjust the offset in either the Sample on the
Hold modes. The fully differential logic inputs have
low input current, and are compatible with TTL, 5V
CMOS, and CMOS logic families.
A
2
5
Output
Offset Adjust
2
30kΩ
Analog
Input
Logic
Logic
Reference
3
A
1
150Ω
6
Hold
Capacitor
8
7
C
1
The SHC298AM is available in a hermetically sealed
8-pin TO-99 package and is specified over a tempera-
ture range from –25°C to +85°C. The SHC298JP and
SHC298JU are 8-pin plastic DIP and SOIC packaged
parts specified over 0°C to +70°C.
The SHC298AJP, specified over 0°C to +70°C, is
available in an 8-pin plastic DIP. The SHC298A grade
features improved gain and offset error, improved drift
over temperature, and faster acquisition time.
The SHC298 family is a price-performance bargain. It
is well suited for use with several 12-bit A/D convert-
ers in data acquisition systems, data distribution
systems, and analog delay circuits.
Mode Control (S/H) Input
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
= 10kΩ, Logic Reference Voltage = 0V, and Logic Voltage = 2.5 V, unless
otherwise noted.
SHC298AM, JP, JU
PARAMETER
ANALOG INPUT
Resistance
Bias Current
(1)
DIGITAL INPUT
Mode Control Truth Table
Pin 7
0V
0V
+2.4V
+0.8V
0.8
1.4
10
2.4
MIN
TYP
10
10
10
MAX
MIN
SHC298AJP
TYP
T
T
Pin 8
+2.4V
+0.8V
+2.8V
+2.8V
MAX
UNITS
Ω
nA
50
25
Circuit State
Sample (Track)
Hold
Hold
Sample (Track)
µA
V
Mode Control and Mode Control Reference Input Current
Differential Logic Threshold
TRANSFER CHARACTERISTICS
ACCURACY (+25
°
C)
Gain
Gain Error
Input Voltage Offset (adjust to zero)
(1)
Droop Rate
(1)
Power Supply Rejection
ACCURACY DRIFT
Gain Drift
Input Offset Drift
Droop Rate at T
J
= +85°C
DYNAMIC CHARACTERISTICS
Aperture Time : Negative Input Step
Positive Input Step
Acquisition Time (C = 1000pF): to
±0.1%,
10V Step
Sample/Hold Transient: Peak Amplitude
Settling to 1mV
Feedthrough (Response to 10V Input Step)
OUTPUT
ANALOG OUTPUT
Voltage Range
Current Range
Impedance (in Hold Mode)
POWER SUPPLY
Rate Voltage
Range
Current
(1)
+1
±0.004
±2
±30
±25
3
15
10
200
150
5
160
1
±0.007
±0.010
±7
±100
4
70
T
±0.001
±1
T
T
1
T
T
T
T
4
T
T
±0.004
±0.005
±2
T
2
25
V/V
%
mV
µV/ms
µV/V
ppm/°C
µV/°C
mV/ms
ns
ns
µs
mV
µs
% of 20V
6
±11.5
±2
0.5
4
15
T
T
T
V
mA
T
T
Ω
VDC
VDC
mA
±5
±4.5
±18
±6.5
T
T
T
T
T
Same as specifications for SHC298AM, JP, JU.
NOTES: (1) These parameters guaranteed over a supply voltage range of
±5V
to =
±18V.
(2) Charge offset is sensitive to stray capacitive coupling between input
logic signals and the hold capacitor. 1pF, for instance, will create an additional 0.5mV step with a 5V logic swing and a 0.01µF hold capacitor. Magnitude of the
charge offset is inversely proportional to hold capacitor value.
®
SHC298/298A
2
PIN CONFIGURATIONS
Top View
Tab
8
+V
CC
1
+V
CC
Logic
Mode Control (S/H) Input
Mode Control
Reference
TO-99
Top View
Plastic DIP/Small Outline
7
+V
CC
1
Logic
8
Mode Control
Input
Offset Adjust
1kΩ
2
24kΩ
6
Offset
Adjust
Hold Cap
2
7
Mode Control
Reference
Analog
Input
3
6
Hold Capacitor
Analog
Input
3
4
–V
CC
5 Output
–V
CC
4
5
Output
ABSOLUTE MAXIMUM RATINGS
Supply Voltage ..................................................................................
±18V
Power Dissipation (Package Limitation) ........................................ 500mV
Junction Temperature, T
J MAX
AM ................................................................................................ 125°C
JP, JU .......................................................................................... 100°C
Operating Temperature Range ....................................... –25°C to +85°C
Storage Temperature Range ........................................ –65°C to +150°C
Input Voltage ....................................................... Equal to Supply Voltage
Logic-to-Logic Reference Differential Voltage
(1)
..................... +7V, –30V
Output Short Circuit Duration ...................................................... Indefinite
Hold Capacitor Short Circuit Duration ................................................. 10s
Lead Temperature (soldering, 10s) ................................................. 300°C
NOTE: (1) Although the differential voltage may not exceed the limits given,
the common-mode voltage on the logic pins may be equal to the supply
voltages without causing damage to the circuit. For proper logic operation,
however, one of the logic pins must always be at least 2V below the positive
supply and 3V above the negative supply.
PACKAGE/ORDERING INFORMATION
PACKAGE
DRAWING
NUMBER
(1)
001
006
182
006
TEMPERATURE
RANGE
–25°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PRODUCT
SHC298AM
SHC298JP
SHC298JU
SHC298AJP
PACKAGE
TO-99
8-Pin Plastic DIP
8-Lead SOIC
8-Pin Plastic DIP
NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix C of Burr-Brown IC Data Book.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN
assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject
to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not
authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.
®
3
SHC298/298A
TYPICAL PERFORMANCE CURVES
At T
J
= +25°C,
±15V
supplies, 1000pF holding capacitor, –11.5V
≤
V
IN
≤
+11.5, R
L
= 10kΩ, Logic Reference Voltage = 0V, and Logic Voltage = 2.5 V, unless
