1994 Burr-Brown Corporation
PDS-1214C
Printed in the U.S.A. May, 1995
Wide-Bandwidth,
DC RESTORATION CIRCUIT
APPLICATIONS
q
BROADCAST/HDTV EQUIPMENT
q
TELECOMMUNICATIONS EQUIPMENT
q
HIGH-SPEED DATA ACQUISITION
q
CAD MONITORS/CCD IMAGE
PROCESSING
q
NANO SECOND PULSE INTEGRATOR/
PEAK DETECTORS
q
PULSE CODE MODULATOR/
DEMODULATOR
q
COMPLETE VIDEO DC LEVEL
RESTORATION
q
SAMPLE/HOLD AMPLIFIER
optimized for low input bias current. The sampling
comparator has two identical high-impedance inputs
and a current source output optimized for low output
bias current and offset voltage; it can be controlled by
a TTL-compatible switching stage within a few
nanoseconds. The transconductance of the OTA and
sampling comparator can be adjusted by an external
resistor, allowing bandwidth, quiescent current, and
gain tradeoffs to be optimized.
The SHC615 is available in SO-14 surface mount and
14-pin plastic DIPs, and is specified over the ex-
tended temperature range of 40
C to +85
C.
FEATURES
q
PROPAGATION DELAY: 2.2ns
q
BANDWIDTH: OTA: 750MHz
Comparator: 280MHz
q
LOW INPUT BIAS CURRENT: 0.3
A
q
SAMPLE/HOLD
SWITCHING TRANSIENTS: +1/7mV
q
SAMPLE/HOLD
FEEDTHROUGH REJECTION: 100dB
q
CHARGE INJECTION: 40fC
q
HOLD COMMAND DELAY TIME: 3.8ns
q
TTL/CMOS HOLD CONTROL
DESCRIPTION
The SHC615 is a complete subsystem for very fast
and precise DC restoration, offset clamping, and low
frequency hum suppression of wideband amplifiers or
buffers. Designed to stabilize the performance of
video signals, it can also be used as a sample/hold
amplifier, high-speed integrator, or peak detector for
nanosecond pulses. A wideband Operational
Transconductance Amplifier (OTA) with a high-im-
pedance cascode current source output and fast sam-
pling comparator set a new standard for high-speed
applications. Both can be used as stand-alone circuits
or combined to form a more complex signal process-
ing stage. The self-biased, bipolar OTA can be viewed
as an ideal voltage-controlled current source and is
Switching
Stage
Biasing
SHC615
SOTA
OTA
1
12
2
11
10
7
9
4
3
13
5
+V
CC
V
CC
I
Q
Adjust
Collector (I
OUT
)
Emitter
C
HOLD
Base
Ground
Hold Control
S/H
In+
S/H
In
Sampling
Comparator (SC)
SHC615
SHC615
SHC615
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
Internet: http://www.burr-brown.com/ FAXLine: (800) 548-6133 (US/Canada Only) Cable: BBRCORP Telex: 066-6491 FAX: (520) 889-1510 Immediate Product Info: (800) 548-6132
2
SHC615
SHC615AP, AU
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
OTA
OFFSET VOLTAGE, V
E
at V
B
= 0
Initial
8
40
mV
vs Temperature
40
V/
C
vs Supply (tracking)
V
CC
=
4.5V to
5.5V
50
55
dB
B-INPUT BIAS CURRENT
Initial
0.3
0.9
A
vs Temperature
1
nA/
C
C-OUTPUT BIAS CURRENT, I
C
at V
B
= 0
Initial
200
77
+100
A
B-INPUT IMPEDANCE
4.4
M
INPUT NOISE
Voltage Noise Density, B-to-E
f
OUT
= 100kHz to 100MHz
2.2
nV/
Hz
Voltage Noise Density, B-to-C
f
OUT
= 100kHz to 100MHz
4.5
nV/
Hz
INPUT VOLTAGE RANGE
3.4
V
OUTPUT
Output Voltage Compliance
3.2
V
C-Current Output
18
20
mA
E-Current Output
18
20
mA
C-Output Impedance
0.5
M
E-Output Impedance
12
Open-Loop Gain
96
dB
TRANSCONDUCTANCE
Small Signal, <200mV
70
mA/V
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.
DC SPECIFICATIONS
At V
CC
=
5V, R
LOAD
= 100
, R
Q
= 300
, R
IN
= 150
and T
A
= +25
C, unless otherwise specified.
3
SHC615
DC SPECIFICATIONS
(CONT)
At V
CC
=
5V, R
LOAD
= 1k
, R
Q
= 300
, and T
A
= +25
C, unless otherwise specified.
SHC615AP, AU
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
COMPARATOR
INPUT BIAS CURRENT
Initial
1.0
5
A
vs Temperature
2.3
nA/
C
C-OUTPUT BIAS CURRENT
Initial
10
50
A
vs Temperature
13
nA/
C
INPUT IMPEDANCE
Input Impedance
0.2
M
INPUT NOISE
Voltage Noise Density
f
OUT
= 100kHz to 100MHz
5
nV/
Hz
INPUT VOLTAGE RANGE
Input Voltage Range
3.0
V
Common-Mode Input Range
3.2
V
OUTPUT
Output Voltage Compliance
3.5
V
C-Current Output
2.5
3.2
mA
C-Output Impedance
620 || 2
k
|| pF
Open-Loop Gain
83
dB
TRANSCONDUCTANCE
Transconductance
22
mA/V
HOLD CONTROL
Logic 1 Voltage
+2
+V
CC
+0.6
V
Logic 0 Voltage
0
0.8
V
Logic 1 Current
V Hold Control = 5.0V
1
A
Logic 0 Current
V Hold Control = 0.8V
0.05
A
TRANSFER CHARACTERISTICS
Charge Injection
Track-To-Hold
40
fC
Feedthrough Rejection
Hold Mode
100
dB
COMPLETE SHC615
POWER SUPPLY
Rated Voltage
5
V
Derated Performance
4.5
5.5
V
Quiescent Current
R
Q
= 300
12
15
18
mA
Quiescent Current Range
Programmable (Useful Range)
3 to
36
mA
TEMPERATURE RANGE
Operating
40
+85
C
Storage
40
+125
C
4
SHC615
AC SPECIFICATIONS
At V
CC
=
5V, R
LOAD
= 100
, R
SOURCE
= 50
,
R
Q
= 300
, and T
A
= +25
C, unless otherwise specified.
SHC615AP, AU
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
FREQUENCY DOMAIN
OTA
LARGE-SIGNAL BANDWIDTH
V
OUT
= 5.0Vp-p
430
MHz
(3dB), (B-to-E)
V
OUT
= 2.8Vp-p
540
MHz
V
OUT
= 1.4Vp-p
620
MHz
SMALL-SIGNAL BANDWIDTH B-TO-E
V
OUT
= 0.2Vp-p
520
MHz
DIFFERENTIAL GAIN (B-TO-E)
f = 4.43MHz, V
OUT
= 0.7Vp-p,
R
L
= 150
1.8
%
R
L
= 500
0.1
%
DIFFERENTIAL PHASE
f = 4.43MHz, V
OUT
= 0.7Vp-p,
R
L
= 150
0.07
(B-to-E)
R
L
= 500
0.01
HARMONIC DISTORTION (B-TO-E)
f = 30MHz, V
OUT
= 1.4Vp-p
Second Harmonic
50
dBc
Third Harmonic
46
dBc
LARGE SIGNAL BANDWIDTH
(3dB), (B-to-C)
V
OUT
= 5.0Vp-p
250
MHz
V
OUT
= 2.8Vp-p
580
MHz
V
OUT
= 1.4Vp-p
750
MHz
SMALL SIGNAL BANDWIDTH
B-to-C
V
OUT
= 0.2Vp-p
680
MHz
COMPARATOR
Sample Mode
BANDWIDTH
I
OUT
= 4mAp-p
240
MHz
(3dB)
I
OUT
= 2mAp-p
270
MHz
I
OUT
= 1mAp-p
280
MHz
TIME DOMAIN
OTA
RISE TIME
2Vp-p Step, 10% to 90%
B-to-E
1.1
ns
B-to-C
1.2
ns
SLEW RATE
2Vp-p,B-to-E
1800
V/
s
B-to-C
1700
V/
s
5Vp-p,B-to-E
3300
V/
s
B-to-C
3000
V/
s
COMPARATOR
RISE TIME
10% to 90%, R
L
=
50
,
I
OUT
=
2mA
(Sample Mode)
C
LOAD
= 1pF
2.5
ns
SLEW RATE
10% to 90%, R
L
=
50
,
I
OUT
=
2mA
(Sample Mode)
C
LOAD
= 1pF
0.95
mA/ns
DYNAMIC CHARACTERISTICS
Propagation Delay Time
t
PDH
, V
OD
= 200mV
2.2
ns
Propagation Delay Time
t
PDL
, V
OD
= 200mV
2.15
ns
Delay Time
Sample-to-Hold
3.8
ns
Hold-to-Sample
3.0
ns
5
SHC615
PIN CONFIGURATION
Top View
DIP, SO-14
BLOCK DIAGRAM
I
Q
Adjust
Emitter, E
Base, B
C
HOLD
V
CC
NC
Hold Control
NC
+V
CC
I
OUT
, Collector, C
S/H In
S/H In+
Ground
NC
1
2
3
4
5
6
7
14
13
12
11
10
9
8
SHC615
Power Supply Voltage (
V
CC
) ..............................................................
6V
Input Voltage
(1)
........................................................................
V
CC
0.7V
Operating Temperature .................................................... 40
C to +85
C
Storage Temperature ...................................................... 40
C to +125
C
Junction Temperature .................................................................... +150
C
Lead Temperature (soldering, 10s) ............................................... +300
C
Hold Control .............................................................. 0.5V to +V
CC
+0.7V
NOTE: (1) Inputs are internally diode-clamped to
V
CC
.
ABSOLUTE MAXIMUM RATINGS
ELECTROSTATIC
DISCHARGE SENSITIVITY
Any integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with ap-
propriate precautions. Failure to observe proper handling and
installation procedures can cause damage.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet published speci-
fications.
PACKAGE
DRAWING TEMPERATURE
PRODUCT
PACKAGE
NUMBER
(1)
RANGE
SHC615AP
Plastic 14-Pin DIP
010
40
C to +85
C
SHC615AU
SO 14-Lead Surface-Mount
235
40
C to +85
C
NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix C of Burr-Brown IC Data Book.
PACKAGE/ORDERING INFORMATION
Switching
Stage
Biasing
SHC615
SOTA
OTA
1
12
2
11
10
7
9
4
3
13
5
+V
CC
V
CC
I
Q
Adjust
Collector
(I
OUT
)
Emitter
C
HOLD
Base
Ground
Hold
Control
S/H
In+
S/H
In
Sampling
Comparator (SC)
PDF 
ZIP