ETC ADC-321

®
ADC-321
®
8-Bit, 50MHz
Video A/D Converter
FEATURES
•
•
•
•
•
•
•
•
•
•
Low power dissipation (180mW max.)
Input signal bandwith (100MHz)
Optional synchronized clamp function
Low input capacitance (15pF typ.)
+5V or +5V/+3.3V power supply operation
Differential nonlinearity (±½LSB max.)
Optional self-biased reference
CMOS/TTL compatible inputs
Outputs 3-state TTL compatible
Surface mount package
INPUT/OUTPUT CONNECTIONS
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
GENERAL DESCRIPTION
The ADC-321 is an 8-bit, high speed, monolithic CMOS, subranging A/D converter. The ADC-321 achieves a sampling rate
comparable to flash converters by employing a sub-ranging
technique which uses multiple comparator blocks each
containing a sample-and-hold amplifier. The ADC-321 can
operate with either a single +5V or dual +5V and +3.3V power
source to allow easy interfacing with 3.3V logic.
An optional synchronous clamp function useful for video signal
processing is provided. The ADC-321 is well suited for the
portable video signal processors due to its low 125mW typical
power dissipation. The ADC-321 also features ±0.5 LSB max.
differential non-linearity, a self bias function that can eliminate the
need for external references, SNR with THD of 45dB, a small
32-pin QFP package and an operating temperature range
of –40 to +85°C
FUNCTION
BIT 8 (LSB)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1 (MSB)
TEST
+DVS (Digital)
TEST
A/D CLOCK
NO CONNECTION
NO CONNECTION
CLAMP IN (CLP)
+AVS (Analog)
PIN
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
FUNCTION
NO CONNECTION
DIGITAL GROUND (DGND)
OUTPUT ENABLE (OE)
CLAMP ENABLE (CLE)
DIGITAL GROUND (DGND)
CLAMP CONTROL (COP)
CLAMP REF. (VREF)
REF. BOTTOM SENSE (VRBS)
REF. BOTTOM (VRB)
ANALOG GROUND (AGND)
ANALOG GROUND (AGND)
ANALOG IN (VIN)
+AVS (Analog)
+AVS (Analog)
REF. TOP (VRT)
REF. TOP SENSE (VRTS)
30 OUTPUT ENABLE
+AVS 16
31 DGND
VRTS 17
VRT 18
+AVS 19
Reference
Supply
+AVS 20
A
A
4-Bit
Lower
Sampling
Comparator
4-Bit
Lower
Encoder
B
B
4-Bit
Upper
Sampling
Comparator
4-Bit
Upper
Encoder
Lower
Data
Latch
1
BIT 8 (LSB)
2
BIT 7
3
BIT 6
4
BIT 5
VIN 21
AGND 22
AGND 23
Clock
Generator
VRB 24
Upper
Data
Latch
5
BIT 4
6
BIT 3
7
BIT 2
8
BIT 1 (MSB)
VRBS 25
12 A/D CLOCK
–
VREF 26
+
D-FF
15 CLAMP IN
9
DGND 28
TEST (Open)
10 +DVS
CLAMP CONTROL 27
11 TEST (Open)
CLAMP ENABLE 29
Figure 1. ADC-321 Functional Block Diagram
DATEL, Inc., Mansfield, MA 02048 (USA.) • Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356 • Email: [email protected] • Internet: www.datel.com
®
®
ADC-321
ABSOLUTE MAXIMUM RATINGS (TA = +25°C)
PARAMETERS
Power Supply Voltage (+AVS, +DVS)
Analog Input Voltage, (VIN)
Reference Input Voltage (VRT, VRB)
Digital Input Voltage (VIH, VIL)
Digital Output Voltage (VOH, VOL)
DIGITAL OUTPUTS
LIMITS
UNITS
–0.5 to 7
–0.5 to +AVS + 0.5
–0.5 to +AVS + 0.5
–0.5 to +AVS + 0.5
–0.5 to +DVS + 0.5
Volts
Volts
Volts
Volts
Volts
Output Data Delay
(OE = 0V, CL = 15pF)
(@ +DVS = +5V)
t PLH
t PHL
t PLH
(@+DVS = +3.3V)
t PHL
3-State Output Enable Time ➆
(RL = 1kΩ, CL = 15pF)
t PZH
(@ +DVS = +5V)
t PZL
t PZH
(@+DVS = +3.3V)
t PZL
3-State Output Disable Time ➇
(RL = 1kΩ, CL = 15pF)
t PHZ, t PLZ
(@+DVS = +5V)
t PHZ, t PLZ
(@+DVS = +3.3V)
FUNCTIONAL SPECIFICATIONS
Typical at TA = 25°C, VRT = +2.5V, VRB = +0.5V, +AVS = +5V, +DVS = +3V to +5.5V,
FS = 50MHz unless otherwise specified.
ANALOG INPUTS
MIN.
TYP.
MAX.
UNITS
Input Voltage Range ➀
Input Capacitance
(@ VIN = +1.5Vdc +0.07VRMS)
Input Signal Bandwidth
–1dB (@ RIN = 33Ω)
–3dB (@ RIN = 33Ω)
+0.5
—
+2.5
Volts
—
15
—
pF
—
—
60
100
—
—
MHz
MHz
Clamp Offset Voltage ➈
Clamp Pulse Width ➉
DIGITAL OUTPUTS
Output Current (OE = 0V) ➄
"1"
(@ +DVS = +5V)
"0"
Output Current (OE = 0V) ➄
(@ +DVS = +3.3V) "1"
"0"
Output Current ➅
(@ OE = +3V)
"1"
"0"
Capacitance
—
TYP.
MAX.
UNITS
5.5
5.5
4.3
4.3
9.5
8.5
11.8
7.6
12.0
12.0
16.3
16.3
ns
ns
ns
ns
2.5
2.5
3.0
3.0
4.5
6.0
7.0
5.0
8.0
8.0
9.0
9.0
ns
ns
ns
ns
3.5
2.5
5.5
5.5
7.5
8.0
ns
ns
0
1.75
20
2.75
40
3.75
mV
µA
8
50
—
—
—
—
—
—
—
—
—
0
±0.7
±0.3
3
1.5
—
—
0.5
—
±1.5
±0.5
—
—
Bit
MHz
MHz
ns
LSB
LSB
%
deg
—
—
—
—
—
—
45
44
44
43
38
32
—
—
—
—
—
—
dB
dB
dB
dB
dB
dB
—
—
—
—
—
—
51
46
49
46
45
45
—
—
—
—
—
—
dB
dB
dB
dB
dB
dB
+4.75
+3.0
0
+5.0
—
—
+5.25
+5.5
100
Volts
Volts
mW
—
—
—
—
25
23
2
125
36
33
3
180
mA
mA
mA
mW
PERFORMANCE
260
4.1
370
5.4
480
7.7
Ω
mA
—
0
1.7
—
—
—
+2.7
—
—
Volts
Volts
Volts
+0.52
1.80
—
+0.56
1.92
—
+0.60
2.04
11
Volts
Volts
pF
–70
20
–50
40
–30
60
mV
mV
2.2
—
—
—
—
+0.8
Volts
Volts
–240
–240
–40
—
—
—
—
—
240
40
240
11
µA
µA
µA
pF
10
10
—
—
—
—
ns
ns
MIN.
TYP.
MAX.
UNITS
Resolution
Sampling Rate, maximum, FS
minimum, FS
Aperature Delay (Tds)
Integral Linearity Error
Diff. Linearity Error
Diff. Gain Error 11
Diff. Phase Error 11
S/N Ratio with THD
(fIN = 100kHz)
(fIN = 500kHz)
(fIN = 1MHz)
(fIN = 3MHz)
(fIN = 10MHz)
(fIN = 25MHz)
Spurious Free Dynamic Range
(fIN = 100kHz)
(fIN = 500kHz)
(fIN = 1MHz)
(fIN = 3MHz)
(fIN = 10MHz)
(fIN = 25MHz)
DIGITAL INPUTS
Logic Levels ➂
Input Voltage "1"
Input Voltage "0"
Input Current ➃
A/D CLK
CLP, CLE
OE
Input Capacitance
A/D Clock Pulse Width
(tpw1)
(tpw0)
MIN.
CLAM CIRCUIT
REFERENCE INPUTS
Reference Resistance
VRT – VRB
Reference Current
Reference Voltage
VRT
VRB
VRT – VRB
Self Bias Voltage ➁
VRB
VRT – VRB
Capacitance (VRT, VRTS, VRB, VRBS)
Offset Voltage
VRT
VRB
(continued)
POWER REQUIREMENTS
Power Supply
+AVS
+DVS
|AGND – DGND|
Power Supply Current 12
1. AIS, DIS (@ +DVS = +5V)
2. AIS
DIS (@ +DVS = +3.3V)
Power Dissipation
—
4
—
—
–2
—
mA
mA
—
2.4
—
—
–1.2
—
mA
mA
ENVIRONMENTAL/PHYSICAL
–40
–40
—
—
—
11
40
40
pF
µA
µA
Operating Temp. Range, Case
Storage Temperature Range
Package Type
Weight
–40
–55
—
+85
—
+150
32-pin, plastic QFP
0.007 ounces (0.2 grams)
°C
°C
Footnotes:
➀
➁
➂
➃
➄
See technical note 6
Pin 25 tied to AGND and pin 17 tied to +AVS
+AVS = +4.75 to +5.25V and +DVS = 3 to +5.5V, full operating tem. range.
VIL = 0V and VIH = +AVS, full operating temp. range
VOH = +DVS–0.8V and VOL = +0.4V, full operating temp. range
➅
➆
➇
➈
+DVS = +3 to +5.5V, full operating temp. range
OE: +3 to 0V change
OE: 0 to +3V change
2.75µs clamp pulse width, 14.3MHz sampling,
15.75kHz clamping rate
2
➉ The clamp pulse width given is for NTSC. For other processing
systems adjust the rate to the clamp pulse cycle (1/15.75kHz for
NTSC) to equal the value for NTSC.
11 NTSC 40IRE ramp, 14.3MHz sampling
12
50MHz sampling, +AVS = +5V
®
®
ADC-321
TECHNICAL NOTES
1. The ADC-321 is a monolithic CMOS device. It should be
handled carefully to prevent static charge pickup.
24) will then be +2.48V and +0.56V respectively. Under an
application where this self bias function is used, the effects of
temperature changes are minimal. Voltage changes of the
+5V supply have direct influence on the performance of the
device. The use of external references is recommended for
applications sensitive to gain error, no ac signals can be
used as references for this device.
2. It has separate power supply terminals +AVS (pins 16, 19
and 20) and +DVS (pin 10) for the internal analog and digital
circuits. It is recommended that both +AVS and +DVS be
powered from a single source
Other external digital circuits must be powered with a
separate +DVS. A time lag between the two power supplies
could induce latch up when power is turned on if separate
supplies are used. The operating range of +DVS is from
+3.0V to +5.5V and it allows the use of a common power
supply with 3.3V digital systems. The +3.3V power for +DVS
in this case should be taken or derived from the +AVS supply
to avoid latch up. No power supply terminal should be left
open.
7. A voltage up to +AVS + 0.5V can be applied to each digital
input even when +3.3V is powered to +DVS, but the digital
output voltage never exceeds +DVS.
8. Layout A/D CLOCK pulse input (pin 12) as short as possible
for minimum influence on other signals. Use of a 100 ohm
series resistor is recommended to protect the device as
there may be some voltage difference and turn-on-time lag
on the power supplies. Analog inputs signals are sampled at
the falling edge of an A/D CLOCK pulse and digital data
become available at the rising edge of an A/D CLOCK pulse
that is delayed by 2.5 clock cycles. The A/D CLOCK are
positive pulse that have 50% duty cycle. The minimum clock
pulse width is 10 nsec for both high and low levels. Keep it
low level while A/D conversions
are on hold.
3. The ADC-321 has separate grounds, the analog GND (pins
22 and 23) and digital GND (pins 28 and 31). Separate and
substantial AGND and DGND ground planes are required.
These grounds have to be connected to one earth point
underneath the device. Digital returns should not flow through
analog grounds. Connect all ground lines to the power point.
4. Bypass all power lines to GND with 0.1µF ceramic chip
capacitors as close to the device as possible. This is
very important.
9. Digital output is 3-state. To enable 3-state outputs connect
the OUTPUT ENABLE (pin 30) to GND. To disable, connect
it to +DVS. The output is recommended to be latched and
buffered through output registers. The device may be
damaged if a voltage higher than +DVS + 0.5V is given to
digital output pins while at high impedance level.
5. Even though the analog input capacitance is a low 15pF, it is
recommended that high frequency input be provided via a
high-speed buffer amplifier. A parasitic oscillation may be
generated when a high-speed amplifier is used. A 33 ohm
resistor inserted between the output of an amplifier and the
analog input of the ADC-321 will improve the situation. Kick
back noise from A/D CLOCK pulses will be observed at the
analog input terminal, but this has no influence on the ADC321 performance.
10. The 50MHz sampling rate is guaranteed. It is not recommended to use this device at sampling rates slower than
500kHz because the droop characteristics of the internal
sample and hold exceed the limit required to maintain the
specified accuracy of the device. Also, burst mode sampling
is not recommended.
6. Apply +2.5V to VRT (pin 18, reference top) and 0.5V to VRB
(pin 24 reference bottom) to obtain an analog input range of
+0.5V to +2.5V. Conversion accuracy is dependent on stable
reference voltages. Provide reference inputs via amplifiers
that have enough driving power to avoid noise problems.
Keep to the following equations;
0V ≤ VRB ≤ VRT ≤ +2.7V,
11. The ADC-321 has a clamp function. This clamp is enabled
when CLAMP ENABLE (pin 29) is tied to GND and is
disabled when tied to +DVS or left open. Clamp pulse inputs
(pin 15) are effective when this clamp function is enabled and
signals are clamped whole, this clamp pulse is low. The
clamp reference input (pin 26) is set by an external trim. The
CCP terminal (pin 27) integrates the clamp control voltage
across an external capacitor. Refer to Figure 4 for examples
of various ways to use this clamp function.
| VRT – VRB | ≥ 1.7V
The ADC-321 has a self bias function which allows the
device to work without external references. Connect VRTS
(pin 17, self bias top) to +AVS and VRBS (pin 25, self bias
bottom) to the analog GND to obtain an analog input range of
+0.56 to +2.48V. Typical voltages at VRT (pin 18) and VRB (pin
12. The TEST 1 and 2 (pins 9 and 11) are not used. Always
leave them open.
3
®
®
ADC-321
THEORY OF OPERATION
comparator block and the lower comparator A block. Input
voltage N+1 is sampled with the falling edge of the second
clock by means of the upper comparator block and lower
comparator B block. The upper comparator block finalizes
comparison data UD(N) with the rising edge of the second
clock. The lower comparator block finalizes comparison
data LD(N) with the rising edge of the third clock. UD(N)
and LD(N) are combined and routed to the output as Output
Data N with the rising edge of the fourth clock. Thus there
is a 2.5 clock delay from the analog input sampling point to
the digital data output.
(See Functional Block Diagram, Figure 1, and Timing
Diagrams, Figure 2)
1. The DATEL ADC-321 is a 2-step parallel A/D converter
featuring a 4-bit upper comparator group and two 4-bit
lower comparator groups, each with built-in sample and
hold. A reference voltage equal to the voltage between
(VRT – VRB)/16 is constantly applied to the 4-bit upper
comparator block. A voltage corresponding to the upper
data is fed through the reference supply to the lower data.
VRTS and VRBS pins provde the self generation function for
VRT (reference voltage top) and VRB (reference voltage
bottom) voltages.
Table 2: Digital Output Coding
2. This converter uses an offset cancelation type comparator
and operates synchronously with the external clock. It
features various operating modes which are shown in the
Timing Diagram (Figure 2) by the symbols S, H and C.
These characters stand for Input Sampling (Auto Zero)
Mode, Input Hold Mode and Comparison Mode.
3. The operation of the respective parts is as indicated in
Figure 2-3. For instance, input voltage N is sampled with
the falling edge of the first clock by means of the upper
tr = 4.5ns
0V
+7.812mV
0 0 0 0
0 0 0 0
0 0 0 0
0 0 0 1
+0.9922V
+1.000V
0 1 1 1
1 0 0 0
1 1 1 1
0 0 0 0
+1.500V
1 1 0 0
0 0 0 0
+1.9922V
1 1 1 1
1 1 1 1
tr = 4.5ns
3V
90%
OE INPUT
OUTPUT CODE
MSB
LSB
VIN
1.3V
10%
tplz
0V
tpzl
VOH
1.3V
OUTPUT 1
10%
VOL /(=DGND)
tpzh
tphz
VOH/(=DGND)
90%
OUTPUT 2
1.3V
VOL
Figure 2-1. ADC-321 Timing Diagram
tr = 4ns
tf = 4ns
3V
90%
CLOCK 1.3V
10%
0V
DATA 0. 7 DV S
OUTPUTS
0. 3 DV S
tpLH
tpHL
Figure 2-2. ADC-321 Timing Diagram
4
®
®
ADC-321
Tds
0ns typ.
N
N+3
N+1
ANALOG
SIGNAL
N+2
TPW0
TPW1
10ns min. 10ns min.
CLOCK 1.3V
TPLH
TPHL
DATA
OUTPUTS
N–3
N–2
N–1
N
1
UPPER SAMPLING
COMPARTOR
S (N)
C (N)
S (N+1)
S (N+2) C (N+2)
C (N+1)
S (N+3) C (N+3)
1
UPPER OUTPUT
DATA
UD (N–1)
UD (N)
UD (N+1)
UD (N+2)
1
LOWER SAMPLING
COMPARTOR 1
S (N)
H (N)
C (N)
S (N+2)
H (N+2)
C (N+2)
1
LOWER OUTPUT
DATA 1
LD (N–2)
LD (N)
1
LOWER SAMPLING
COMPARTOR 2
H (N–1)
C (N–1)
S (N+1)
H (N+1)
C (N+1)
S (N+3)
H (N+3)
1
LOWER OUTPUT
DATA 2
LD (N–3)
LD (N–1)
LD (N+1)
S = Sample Mode, H = Hold Mode, C = Comparate Mode
1
Internal Operation of the ADC-321
Figure 2-3. ADC-321 Timing Diagram
A/D CLOCK
+5V (A)
0.1µF 0.1µF 0.1µF
+12V
+5V (A)
+5V (D)
10µH
+12V
16
500
47µF
500
0.1µF
100
0.1µF
0.1µF
47µF
74HC04
15
47µF
14
13
12
11
10
9
17
8
BIT 1 (MSB)
18
7
BIT 2
19
6
BIT 3
0.1µF
0.1µF
10µF
20
5
BIT 4
21
4
BIT 5
22
3
BIT 6
23
2
BIT 7
1
BIT 8 (LSB)
ADC-321
0.1µF
180
ANALOG IN
33
500
10pF
5k
470µF
1k
120
2k
0.1µF
24
–12V
+12V
47µF
0.1µF
25
26
27
28
–12V
1k
1k
10µH
5V
500
Figure 3. Typical Connection Diagram
5
29
30
31
32
®
®
ADC-321
CLAMP
PULSE
+5V (A)
+5V (A)
A/D CLOCK
+5V (D)
A/D CLOCK
+5V (D)
16 15
14
13
12 11
16 15
9
10
8
17
VRT
10
9
7
19
6
20
5
21
4
22
3
2
19
6
20
5
21
4
22
3
23
2
23
24
1
24
33
12 11
8
7
ANALOG
IN
13
18
18
ANALOG IN
14
17
33
10pF
25 26
27
28 29
30
10µF
32
31
10pF
1
25 26
VRB
27
28 29
30
31
32
+5V (A)
20k
Figure 4-1. Clamp Not Used in Self Bias Mode
0.01µF
Figure 4-2. Clamp Used in External Reference Mode
CLAMP
PULSE
A/D CLOCK
+5V (D)
16 15
ANALOG
IN
10µF
14
13
12 11
8
18
7
19
6
20
5
21
4
22
3
23
+5V (A)
ANALOG
IN
10µF
27
28 29
30
12 11
10
9
8
18
7
19
6
20
5
21
4
10pF
22
3
23
2
Clamp
Level
Data
1
25 26
32
31
13
24
1
25 26
14
17
33
2
24
+5V (D)
16 15
9
10
17
33
10pF
A/D CLOCK
+5V (A)
Comparator
+5V (A)
27
28 29
30
31
32
D/A
20k
0.01µF
0.01µF
Figure 4-3. Clamp Used in Self Bias Mode
Figure 4-4. Digital Clamp Used in Self Bias Mode
CLAMP PULSE
+5V (A)
A/D CLOCK
+3.3V (D)
16 15
14
13
12 11
10
9
17
8
18
7
19
6
20
5
21
4
22
3
23
2
ANALOG IN
33
10µF
10pF
+5V (A)
20k
24
1
25 26
27
28 29
30
31
32
0.01µF
Figure 4-5. Clamp Used in Self Bias Mode With +5V/+3.3V Dual Power Supply
6
®
®
ADC-321
Ambient Temperature vs.
Sampling Delay
Analog Input Bandwidth
Analog Input Frequency vs.
S/N + THD, Effective Bit
FS = 50MHz
AVS = DVS = 5V
VIN = 2Vp-p
TA = 25°C
–1
–1
FS = 50MHz
Sine wave 1Vp-p input
AVS = DVS +5V
TA = 25°C
–2
0.1
0
+25
+50
+75
Ambient Temperature (°C)
50
FS = 50MHz
AVS = DVS = 5V
VIN = 2Vp-p
TA = 25°C
30
12
10
tplh
8
tphl
–20
tplh
–20
FS = 50MHz
AVS = DVS +5V
C L = 15pF
8
tphl
6
0
5
24
Supply Current (mA)
25
4.75
1
Max. Sampling Rate (MHz)
10
Input Frequency (MHz)
5
Supply Voltage (V)
tplh
10
8
tphl
6
3
25
20
AVS = DVS = +5V
15
10
60
0
25
50
75
Ambient Temperature (°C)
Figure 5: Typical Performance Curves
7
20
30
40
50
Sampling Frequency (MHz)
Supply Voltage vs.
Sampling Rate
65
–20
3.5
4.5
5
5.5
Ambient Temperature (°C)
25
5.25
FS = 50MHz
fin = 1kHz, triangular wave input
AVS = DVS +5V
70
FS = 10MHz
+AVS = +5V
TA = 25°C
Sampling Rate vs.
Supply Current
FS = 50MHz
AVS = DVS
TA = 25°C
23
0
+25
+50
+75
Ambient Temperature (°C)
12
Ambient Temperature vs.
Max. Sampling Rate
FS = 50MHz
Sine wave 1.9Vp-p
AVS = DVS = +5V
TA = 25°C
0.1
–20
25
25
0
+25
+50
+75
Ambient Temperature (°C)
25
0.01
20
27
Input Frequency vs.
Supply Current
30
15
FS = 50MHz
AVS = DVS +5V
CL = 15pF
6
Supply Voltage vs.
Supply Current
FS = 50MHz
AVS = DVS = +5V
35
10
tphl
Load Capacitance (pF)
Ambient Temperature vs.
Supply Current
–20
FS = 10MHz
AVS = +5V
DVS = +3.3V
TA = 25°C
tplh
10
0
+25
+50
+75
Load Capacitance (pF)
26
8
Ambient Temperature vs.
Output Data Delay
14
12
tplh
10
0
+25
+50
+75
Ambient Temperature (°C)
Output Data Delay (ns)
10
Output Data Delay (ns)
12
6
12
Load Capacitance vs.
Output Data Delay
Load Capacitance vs.
Output Data Delay
tphl
FS = 50MHz
AVS = DVS +5V
CL = 15pF
6
0.1
1
0.01
10
Analog Input Frequency (MHz)
8
Ambient Temperature vs.
Output Data Delay
Supply Current (mA)
30
1
0.1
0.01
10
Analog Input Frequency (MHz)
0.1
10
100
Analog Input Frequency (MHz)
Sampling Rate (MHz)
40
Output Data Delay (ns)
FSDR (dB)
5
40
Ambient Temperature vs.
Output Data Delay
60
Output Data Delay (ns)
6
Output Data Delay (ns)
Analog Input Frequency
vs. FSDR
Supply Current (mA)
7
–3
–20
Supply Current (mA)
50
8
SNR (dB)
0
Effective Bit (dB)
1
Output Level (dB)
Sampling Delay (ns)
0
FS = 50MHz
AVS = DVS = 5V
67
65
AVS = DVS
63
4.75
5
Supply Voltage (V)
5.25
®
®
ADC-321
DIGITAL OUTPUT
ANALOG INPUT
REFERENCE INPUT
+AVS
+DVS
+AVS
VRTS
1 to 8
V RB
21
V RT
24
25
VRBS
Rref
RB
DGND
A/D CLOCK
CLAMP REFERENCE
VOLTAGE INPUT (VREF)
+AVS
12
CLAMP CONTROL
VOLTAGE (CCP)
OUTPUT ENABLE
(OE)
+AVS
+AVS
28
AGND
AGND
AGND
CLAMP PULSE INPUT (CLP)
CLAMP ENABLE (CLE)
+AVS
27
+AVS
15
29
30
AGND
AGND
AGND
AGND
Figure 6: Equivalent Circuits
0.35 ±0.008
(9.0 ±0.2)
MECHANNICAL DIMENSIONS
INCHES (mm)
0.280 ±0.008
(7.1 ±0.2)
24
17
25
16
32
9
8
1
0.03
(0.8)
0.012 ±0.005
(0.03 –0.1, +0.15)
0.02
(0.5)
0.039 ±0.010
(1.5 ±0.35)
0.315
(8.0)
0.006 ±0.006
(0.15 ±0.15)
0 to 10°
0.006 ±0.003
(0.152 ±0.075)
ORDERING INFORMATION
ADC-321
8-bit, 50MHz A/D converter
ISO 9001
R
E
G
I
S
T
E
R
E
D
DS-0359
DATEL, Inc. 11 Cabot Boulevard, Mansfield, MA 02048-1151
Tel: (508) 339-3000
(800) 233-2765 Fax: (508) 339-6356
Internet: www.datel.com
Email: [email protected]
Data sheet fax back: (508) 261-2857
DATEL
DATEL
DATEL
DATEL
6/98
(UK) LTD. Tadley, England Tel: (01256)-880444
S.A.R.L. Montigny Le Bretonneux, France Tel: 01-34-60-01-01
GmbH Munchen, Germany Tel: 89-544334-0
KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-354-2025
DATEL makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained
herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. The DATEL logo is a registered DATEL, Inc. trademark.