®
®
SHM-14
Ultra-Fast, 14-Bit Linear
Monolithic Sample-Hold Amplifiers
IN N O VA T IO N a n d E X C E L L E N C E
FEATURES
•
Fast acquisition time:
10ns to ±0.1%
20ns to ±0.024%
25ns to ±0.012%
•
±0.0012% Nonlinearity
•
65µV rms output noise
•
250MHz small signal bandwidth
•
70MHz full power bandwidth
•
–80dB feedthrough
•
1ps Aperture jitter
•
250mW power dissipation
•
Low cost
INPUT/OUTPUT CONNECTIONS — SOIC
PIN
1
2
3
4
5
6
7
8
FUNCTION
–5V SUPPLY
DO NOT CONNECT
ANALOG INPUT
DO NOT CONNECT
–5V SUPPLY
DO NOT CONNECT
DO NOT CONNECT
–5V SUPPLY
PIN
16
15
14
13
12
11
10
9
FUNCTION
SAMPLE/HOLD
SAMPLE/HOLD
+5V SUPPLY
EXT. CAPACITOR
GROUND
+5V SUPPLY
+5V SUPPLY
ANALOG OUTPUT
GENERAL DESCRIPTION
The SHM-14 is an extremely high-speed and accurate
monolithic sample-and-hold amplifier designed for fast data
acquisition applications. The SHM-14 is accurate (±0.5 LSB to
14-bits over the full military temperature range) and is very fast
(10ns and 20ns acquisition times to accuracies of 10 and 12
bits respectively). With this high performance and a full power
bandwidth of 70MHz, the SHM-14 is an ideal device for driving
flash and high-resolution subranging A/D converters.
A careful design optimizes the device for accuracy and speed
over the full military temperature range. The droop rate is a low
±2mV/µs and can be further reduced by adding an optional
external hold capacitor. The 30mA output current and
guaranteed specifications for a 100Ω load provide high drive
capability. Operating from ± 5V supplies, the SHM-14
consumes only 250mW of power.
The SHM-14 is built using a fast complementary bipolar
process. The device is available in both military and industrial
temperature ranges. The SHM-14 is packaged in a 16-pin
plastic SOIC or in a 20-pin ceramic LCC.
INPUT/OUTPUT CONNECTIONS — CLCC
PIN
1
2
3
4
5
6
7
8
9
10
FUNCTION
NOT CONNECTED
–5V SUPPLY
NOT CONNECTED
ANALOG INPUT
NOT CONNECTED
DO NOT CONNECT
–5V SUPPLY
DO NOT CONNECT
DO NOT CONNECT
–5V SUPPLY
PIN
20
19
18
17
16
15
14
13
12
11
FUNCTION
NOT CONNECTED
SAMPLE/HOLD
SAMPLE/HOLD
+5V SUPPLY
NOT CONNECTED
EXT. CAPACITOR
GROUND
+5V SUPPLY
+5V SUPPLY
ANALOG OUTPUT
–5V SUPPLY
1, 5, 8
EXTERNAL HOLD
CAPACITOR
13
+5V SUPPLY
10, 11, 14
ANALOG INPUT
3
+1
C
H
15pF
+1
9
ANALOG
OUTPUT
SAMPLE/HOLD
SAMPLE/HOLD
15
16
SWITCH
DRIVE
2, 4, 6, 7
DO NOT CONNECT
12
Note: SOIC Package Pinouts Shown
GROUND
Figure 1. SHM-14 Functional Block Diagram
DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048-1151 (U.S.A.)
•
Tel: (508) 339-3000 Fax: (508) 339-6356
•
For immediate assistance (800) 233-2765
®
®
SHM-14
ABSOLUTE MAXIMUM RATINGS
PARAMETERS
+5V Supply
–5V Supply
Analog Input
LIMITS
UNITS
Volts
Volts
Volts
Volts
mA
Volts
°C
°C
0 to +6
0 to –6
+5V Supply –1
–5V Supply +1
Continuous Output Current
±50
Digital Inputs
<Supply Voltages
Junction Temperature
+175
Lead Temperature
(10 seconds)
+300
Output shorted to any supply will cause permanent damage.
PERFORMANCE (Cont.)
Acquisition Time
(±0.1%, ±2V)
–40 to +85°C
–55 to +125°C
Hold Mode Settling
(±0.012%)
–40 to +85°C
–55 to +125°C
Hold Mode Settling
(±0.024%)
–40 to +85°C
–55 to +125°C
Hold Mode Settling
(±0.05%)
–40 to +85°C
–55 to +125°C
Hold Mode Settling
(±0.1%)
–40 to +85°C
–55 to +125°C
Slew Rate
Full Power Bandwidth
(±1V)
Small Signal Bandwidth
Output Noise, Hold Mode
Feedthrough
(2V Step)
Droop Rate
+25°C
–40 to +85°C
–55 to +125°C
POWER SUPPLY REQUIREMENTS
Power Supply Range
+5V Supply
–5V Supply
Power Supply Current
+5V Supply
–5V Supply
Power Dissipation
Power Supply Rejection Ratio
ENVIRONMENTAL
—
—
—
—
—
—
—
—
—
+0.98
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
±0.0012
—
—
±0.002
—
±0.003
±12
—
—
±3
—
—
+0.995
—
—
2
2
1
1
–72
–58
—
—
25
35
20
25
19
20
—
±20
±30
—
±20
±20
—
±20
±30
—
—
—
—
—
—
–50
–48
—
—
35
40
30
35
%
%
%
mV
mV
mV
mV
mV
mV
V/V
ppm/°C
ppm/°C
ns
ns
ps rms
ps rms
dB
dB
dB
dB
ns
ns
ns
ns
ns
ns
Operating Temp. Range, Case
SHM-14S, SHM-14L
SHM-14LM
Storage Temperature Range
Package Type
SHM-14S
SHM-14L, SHM-14LM
Footnotes:
•
Short circuit protection at ±50mA.
–40
–55
–65
—
—
—
+85
+125
+150
°C
°C
°C
+4.5
–5.5
+17
–17
170
40
+5
–5
+25
–25
250
60
+5.5
–4.5
+30
–30
300
—
Volts
Volts
mA
mA
mW
dB
MIN.
—
—
—
—
—
—
—
—
—
—
±300
45
100
—
—
—
—
—
TYP.
10
10
12
15
7
7
6
6
5
5
±430
70
250
65
–80
±2
±5
±10
MAX. UNITS
16
19
—
—
18
18
16
16
12
12
—
—
—
—
—
±6
±15
±30
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
V/µs
MHz
MHz
µVrms
dB
mV/µs
mV/µs
mV/µs
FUNCTIONAL SPECIFICATIONS
(Apply over the operating temperature range using a 100Ω resistive load, 10pF
capacitive load, ECL digital input levels, and ±5V nominal supplies, unless specified.)
INPUTS
Input Voltage Range
Input Impedance
Digitals Inputs
(Balanced ECL)
Logic Levels
Logic 1
Logic 0
Logic Loading
Logic 1
Logic 0
OUTPUTS
Output Voltage Range
Output Current
•
Output Impedance
(dc)
Stable Capacitive Load
PERFORMANCE
Nonlinearity
(±1V)
+25°C
–40 to +85°C
–55 to +125°C
Sample Mode Offset
+25°C
–40 to +85°C
–55 to +125°C
Pedestal
+25°C
–40 to +85°C
–55 to +125°C
Gain,
+25°C
Gain Drift
(±1V)
–40 to +85°C
–55 to +125°C
Aperture Delay
–40 to +85°C
–55 to +125°C
Aperture Jitter
–40 to +85°C
–55 to +125°C
Harmonic Distortion
(±1V)
dc to 1MHz
dc to 10MHz
+25°C
–40 to +85°C
–55 to +125°C
Acquisition Time
(±0.012%, ±2V)
–40 to +85°C
–55 to +125°C
Acquisition Time
(±0.024%, ±2V)
–40 to +85°C
–55 to +125°C
Acquisition Time
(±0.05%, ±2V)
–40 to +85°C
–55 to +125°C
–2.5
± 30
—
—
—
—
0.3
—
+2.5
—
1
50
Volts
mA
Ω
pF
MIN.
–2.5
0.3
–1.5
–2.5
—
—
TYP.
—
1
—
—
+10
–30
MAX.
+2.5
—
+1.8
+0.8
+50
–150
UNITS
Volts
MΩ
Volts
Volts
µA
µA
16-Pin plastic SOIC
20-Pin ceramic LCC
TECHNICAL NOTES
The SHM-14 employs an open loop architecture in order to
achieve its superior high-speed characteristics. The first stage
buffer amplifier, which charges the hold capacitor, incorporates the
sample-and-hold switch into its design. This technique allows for a
fast acquisition time which is not limited by slew current like the
traditional Schottky diode bridge switch. The output amplifier uses
a closed loop voltage feedback design which provides a low (0.3Ω,
typical) output impedance. Gain and linearity are not affected by
heavy loads.
The design has been optimized to achieve the high accuracy associ-
ated with fast transient responses over the full military temperature
range. During the track-to-hold transient, the integral nonlinearity is
not affected and the pedestal remains constant over the full ±2.5V
input range.
An external hold capacitor can be added to the 15pF internal hold
capacitor to obtain a lower droop rate (the droop rate is propor-
tional to the inverse of the total hold capacitor value) without
increasing transient response times by more than few ns. Settling
and acquisition times are typically increased by 5ns and 10ns
respectively for 47pF and 100pF external hold capacitors. The
external hold capacitor should not exceed 100pF.
2
®
®
SHM-14
GROUNDING AND LAYOUT
Obtaining fully specified performance from the SHM-14 requires
careful attention to pc-board layout and power supply decoupling.
For optimal performance, tie all grounds directly to a large ana-
log ground plane beneath and around the package. Bypass all
power supplies to ground with 10µF tantalum capacitors in par-
allel with 0.1µF ceramic capacitors.
SHM-14
16 (19)
Locate the bypass capacitors as close to the unit as possible.
For best performance, controlled impedance transmission line
techniques, such as microstrip, should be used. Mount all com-
ponents as close to the required pins as possible. It is strongly
recommended that the SHM-14 not be socket-mounted.
50
Ω
SAMPLE / HOLD
50
Ω
SAMPLE
0.1µF
1 (2)
–5V SUPPLY
SAMPLE / HOLD
15 (18)
0.1µF
14 (17)
+5V SUPPLY
ANALOG
INPUT
50
Ω
5 (7)
0.1µF
+5V SUPPLY
+5V SUPPLY
10µF
8 (10)
– 5V SUPPLY
ANALOG OUTPUT
10µF
R Load
100
Ω
+
9 (11)
0.1µF
ANALOG
OUTPUT
10 (12)
– 5V SUPPLY
3 (4)
INPUT
EXTERNAL HOLD
CAPACITOR
GROUND
13 (15)
C
HOLD
Refer to Table 1 for optional
HOLD capacitor values.
HOLD
12 (14)
0.1µF
11 (13)
+
NOTES:
0.1µF
1. Pin numbers in ( ) are for CLCC package.
2. For SOIC package:
Pins 2, 4, 6, 7 DO NOT CONNECT
3. For CLCC package:
Pins 1, 3, 5, 16, 20 NOT CONNECTED
Pins 6, 8, 9 DO NOT CONNECT
0.1µF
– 5V
+5V
Figure 2. SHM-14 Simplified Connection Diagram
-0.8 V
HOLD
-1.8 V
-0.8 V
SAMPLE
-1.8 V
+1 V
ANALOG
INPUT
-1 V
20ns typ.
+1 V
ANALOG
OUTPUT
-1 V
7ns typ.
7ns typ.
Acquisition
Time to
±0.024%
SAMPLE
HOLD
SAMPLE
HOLD
Feedthrough -80dB
Track-to-hold Settling
to ±0.024%
20ns typ.
Figure 3. SHM-14 Control and Timing
3
®
®
SHM-14
Evaluation Board
for CLCC-20 Version
0.1µF
130
Ω
–5V SUPPLY
16, 17, 18, 19
SAMPLE
SHM-14
2
0.1µF
SAMPLE / HOLD
ANALOG
INPUT
20
–5V SUPPLY
19
SAMPLE / HOLD
82
Ω
130
Ω
14
18
17, 20
15
14, 16
13
12
11
0.1µF
C
HOLD
0.1µF
82
Ω
4
HOLD
13
INPUT
+5V SUPPLY
EXTERNAL HOLD
CAPACITOR
51
Ω
0.1µF
7
–5V SUPPLY
GROUND
+5V SUPPLY
+5V SUPPLY
Refer to Table 1. for optional
HOLD capacitor values.
+5V SUPPLY
6, 7, 8, 9, 10
–5V SUPPLY
11, 12, 15
10
0.1µF
–5V SUPPLY
OUTPUT
ANALOG
OUTPUT
5
GROUND
1, 2, 3, 4
GROUND PLANE
Figure 4. SHM-14 Evaluation Board Schematic
Table 1. Optional External HOLD Capacitor
Model
SHM-14L, -14S
SHM-14LM
Operating
Temperature Range
–40 to +85°C
–55 to +125°C
Type of HOLD Capacitor
(Ceramic,
≤100pF,
±10%)
Type I or II, NPO or X7R
Type I or NPO
4
®
®
SHM-14
INCHES
(mm)
0.43
(11)
0.13
(3.3)
PLASTIC
STANDOFF
(TOP VIEW)
0.85
(21.59)
0.100
(2.54)
20
19
18
17
C1
C5
C4
R1
C2
C3
1
2
3
4
5
6
7
8
9
10
0.018
(0.45)
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
1.10
(27.94)
16
15
14
C7
R4
R3
C
EXT
13
12
11
C6 R6
R5
(BOTTOM VIEW)
0.95
(24.13)
Figure 5. SHM-14 Evaluation Board Dimensions
SHM-14 Evaluation Board Connections
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
FUNCTION
GROUND
GROUND
GROUND
GROUND
ANALOG OUTPUT
+5V SUPPLY
+5V SUPPLY
+5V SUPPLY
+5V SUPPLY
+5V SUPPLY
–5V SUPPLY
–5V SUPPLY
HOLD
SAMPLE
–5V SUPPLY
–5V SUPPLY
–5V SUPPLY
–5V SUPPLY
–5V SUPPLY
ANALOG INPUT
5
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