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19-1205; Rev 2; 5/98
8-Bit, Ultra-High-Speed DAC
________________General Description
The MAX5140 is a monolithic, 8-bit digital-to-analog
converter (DAC) capable of accepting video data at
400Msps. Complete with video controls (sync, blank,
reference white (force high), and bright), the MAX5140
directly drives doubly terminated 50Ω or 75Ω loads to
standard composite video levels. Standard setup level
is 7.5IRE. The MAX5140 includes an internal precision
bandgap reference that can drive two other MAX5140s
in an RGB graphics system.
The MAX5140 is available in a 24-pin PDIP package in
the -20°C to +85°C industrial temperature range.
____________________________Features
o
400Msps Nominal Conversion Rate
o
RS-343-A Compatible
o
Complete Video Controls: Sync, Blank, Bright,
and Reference White (force high)
o
ECL Compatible
o
Single Power Supply
o
Registered Data and Video Controls
o
Differential Current Outputs
o
Stable On-Chip Bandgap Reference
o
50Ω and 75Ω Output Drive
o
ESD-Protected Data and Control Inputs
MAX5140
________________________Applications
Raster Graphics
High-Resolution Color or Monochrome Displays
to 2k x 2k Pixels
Medical Electronics: CAT, PET, and MR Imaging
Displays
CAD/CAE Workstations
Solids Modeling
General-Purpose, High-Speed Digital-to-Analog
Conversion
Digital Synthesizers
Automated Test Equipment
Digital Transmitters/Modulators
Ordering Information
PART
MAX5140IPG
TEMP. RANGE
-20°C to +85°C
PIN-PACKAGE
24 Plastic DIP
Pin Configuration
TOP VIEW
D3 1
D2 2
D1 3
D0 4
V
EE
5
CONV 6
CONV 7
FT 8
V
CC
9
FH 10
Blank 11
BRT 12
24 D4
Sync, Blank, Bright, Ref - White
Functional Diagram
23 D5
22 D6
21 D7
Video Controls In
4
Video Data In
D0 - D3
4
4
4
Out +
Register
Video Data In
D4 - D7
(MSBs)
4
Output
Current
Switches
Out -
MAX5140
20 V
EE
19 Out+
18 Out-
17 V
CC
16 I
Set
15 Ref In
14 Ref Out
13 Sync
4 To 15
Decode
Feedthrough
Convert
2
ISet
Ref In
Ref Out
Ref
Buffer
Bandgap
Reference
DIP
________________________________________________________________
Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 408-737-7600 ext. 3468.
8-Bit, Ultra-High-Speed DAC
MAX5140
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
V
EE
(measured to V
CC
)..........................................-7.0V to 0.5V
Input Voltages
CONV, Data, and Controls (measured to V
CC
)........V
EE
to 0.5V
Ref+ (measured to V
CC
) ..........................................V
EE
to 0.5V
Ref- (measured to V
CC
)............................................V
EE
to 0.5V
Operating Temperature Ranges
Ambient .............................................................-20°C to +85°C
Junction..........................................................................+175°C
Lead Temperature (soldering, 10sec) .............................+300°C
Storage Temperature Range .............................-60°C to +150°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(V
CC
= ground, V
EE
= -5.2V ±0.3V, C
C
= 0pF, I
SET
= 1.105mA, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
Integral Linearity Error
Differential Linearity Error
Gain Error
Gain-Error Tempco
Bandgap Tempco
Input Capacitance,
I
SET
, Ref Out
Compliance Voltage,
Positive Output
Compliance Voltage,
Negative Output
Equivalent Output
Resistance
Output Capacitance
Maximum Current,
Positive Output
Maximum Current,
Negative Output
Output Offset Current
Input Voltage, Logic High
Input Voltage, Logic Low
Convert Voltage,
Common-Mode Range
Convert Voltage,
Differential
Input Current, Logic Low,
Data and Controls
Input Current, Logic High,
Data and Controls
Input Current, Convert
I
IL
I
IH
I
CONV
R
OUT
C
OUT
I
O+(MAX)
I
O-(MAX)
I
OS
V
IH
V
IL
C
REF
SYMBOL
ILE
DLE
CONDITIONS
1.0mA < I
SET
< 1.3mA
1.0mA < I
SET
< 1.3mA
TEST
LEVEL
VI
VI
VI
V
V
V
VI
VI
VI
V
IV
IV
VI
VI
VI
IV
IV
VI
VI
VI
-0.5
0.4
35
40
2
-1.0
-1.5
-2.5
1.2
120
120
60
45
-45
0.05
0.5
-1.2
-1.2
20
9
MIN
-0.37
-0.95
-0.2
-0.5
-6.5
150
100
5
1.5
1.5
TYP
MAX
0.37
0.95
0.2
0.5
6.5
UNITS
% Full Scale
LSB
% Full Scale
LSB
% Full Scale
ppm/°C
ppm/°C
pF
V
V
kΩ
pF
mA
mA
LSB
V
V
V
V
µA
µA
µA
2
_______________________________________________________________________________________
8-Bit, Ultra-High-Speed DAC
DC ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= ground, V
EE
= -5.2V ±0.3V, C
C
= 0pF, I
SET
= 1.105mA, T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
PARAMETER
Reference Voltage
(measured to V
CC
)
Reference Output Current
Input Capacitance, Data
and Controls
Power-Supply Sensitivity
Supply Current
SYMBOL
V
REF
I
REF
C
IN
CONDITIONS
TEST
LEVEL
VI
VI
V
VI
VI
-120
MIN
-1.3
-50
3
20
155
120
220
TYP
-1.2
MAX
-1.0
UNITS
V
µA
pF
µA/V
mA
MAX5140
I
EE
AC ELECTRICAL CHARACTERISTICS
(R
L
= 37.5Ω, C
L
= 5pF, I
SET
= 1.105mA, T
A
= +25°C, unless otherwise noted.)
PARAMETER
Maximum Conversion Rate
Rise Time
Current-Settling Time,
Clocked Mode
Clock to Output Delay,
Clocked Mode
Data to Output Delay,
Transparent Mode
Glitch Energy
Convert Pulse Width
Reference Bandwidth
Setup Time, Data and
Controls
Hold Time, Data and
Controls
Slew Rate
Clock Feedthrough
t
PWH
,
t
PWL
-3dB
t
S
t
H
20% to 80% G.S.
t
R
t
SI
t
DSC
t
DST
10% to 90% G.S.
To 0.2% G.S.
T
A
= T
MIN
to T
MAX
T
A
= T
MIN
to T
MAX
Area = 1/2VT
R
L
= 25Ω
R
L
= 25Ω
SYMBOL
CONDITIONS
TEST
LEVEL
IV
IV
V
III
IV
III
IV
V
III
V
III
III
V
III
1.0
0.5
700
-48
1.3
1.25
4
3
2.2
3.2
4
MIN
385
TYP
400
900
600
MAX
UNITS
Msps
ps
ns
4
4.5
6
6
ns
ns
pV-s
ns
MHz
ns
ns
V/µs
dB
TEST-LEVEL CODES
All electrical characteristics are subject to
the following conditions:
All parameters having min/max specifica-
tions are guaranteed. The Test Level column
indicates the specific device testing actually
performed during production and Quality
Assurance inspection. Any blank section in
the data column indicates that the specifica-
tion is not tested at the specified condition.
Unless otherwise noted, all tests are pulsed
tests; therefore, T
j
= T
C
= T
A
.
TEST LEVEL
I
II
III
IV
V
VI
TEST PROCEDURE
100% production tested at the specified temperature.
100% production tested at T
A
= +25°C, and sample-
tested at the specified temperatures.
QA sample tested at only the specified temperatures.
Parameter is guaranteed (but not tested) by design
and characterization data.
Parameter is a typical value for reference.
100% production tested at T
A
= +25°C. Parameter is
guaranteed over specified temperature range.
_______________________________________________________________________________________
3
8-Bit, Ultra-High-Speed DAC
MAX5140
______________________________________________________________Pin Description
PIN
1, 2, 3
4
5, 20
6
7
8
9, 17
10
11
12
13
14
15
16
18
19
21
22, 23, 24
NAME
D3, D2, D1
D0
V
EE
CONV
CONV
FT
V
CC
FH
Blank
BRT
Sync
Ref Out
Ref In
I
Set
Out-
Out+
D7
D6, D5, D4
Data Bits 3, 2, and 1
Data Bit 0 (LSB)
Negative Supply
Convert Clock Input
Convert-Clock-Input Complement
Register Feedthrough Control
Positive Supply
Data Force-High Control
Video Blank Input
Video Bright Input
Video Sync Input
Reference Output
Reference Input
Reference Current
Output Current Negative
Output Current Positive
Data Bit 7 (MSB)
Data Bits 6, 5, and 4
FUNCTION
Detailed Description
The MAX5140 is an ultra-high-speed video digital-to-
analog converter (DAC) capable of up to 400Msps con-
version rates. This high speed makes the device
suitable for driving 2048 x 2048 pixel displays at 60Hz
to 90Hz update rates.
In addition, the MAX5140 includes an internal bandgap
reference, which may be used to drive two other
MAX5140s, if desired.
The MAX5140 has ECL logic-level-compatible video
control and data inputs. The complementary analog
output currents produced by the devices are propor-
tional to the product of the digital control and data
inputs in conjunction with the analog reference current.
The MAX5140 is segmented so that the input data’s
four MSBs are separated into a parallel thermometer
code. From here, fifteen identical current sinks are driv-
en to fabricate sixteen coarse output levels. The
remaining four LSBs drive four binary-weighted current
switches.
4
MSB currents are then summed with the LSBs that con-
tribute one-sixteenth of full-scale to provide the 256 dis-
tinct analog output levels.
The video-control inputs drive weighted current sinks,
which are added to the output current to produce com-
posite video-output levels. These controls (sync, blank,
reference white (force high), and bright) are required in
video applications.
A feature that similar video DACs do not have is feed-
through control. The feedthrough pin (FT) allows regis-
tered or unregistered operation of the video control and
data inputs. In registered mode, the composite func-
tions are latched to the pixel data to prevent screen-
edge distortions (generally found on unregistered video
DACs).
_______________________________________________________________________________________
8-Bit, Ultra-High-Speed DAC
MAX5140
*An external reference can be used, or the Ref Out reference
can drive three MAX5140s.
Figure 1. Typical Interface Circuit
Applications Information
General
Figure 1 shows a typical interface circuit using the
MAX5140 in a color-raster application. The MAX5140
requires few external components and is extremely
easy to use. The MAX5140’s ultra-high operating
speeds require good circuit layout, supply decoupling,
and proper transmission-line design. For best perfor-
mance, note the following considerations.
Input Considerations
Video-input data and controls can be directly con-
nected to the MAX5140. Note that all ECL inputs are
terminated as closely to the device as possible to
reduce ringing, crosstalk, and reflections. Maxim rec-
ommends that stripline or microstrip techniques be
used for all ECL interfaces. A convenient and common-
ly used microstrip impedance is about 130Ω, which is
easily terminated using a 330Ω resistor to V
EE
and a
220Ω resistor to ground. This arrangement gives a
Thevenin-equivalent termination of 130Ω to -2V without
the need for a -2V supply. Standard single in-line pack-
age (SIP) 220/330 resistor networks are available for
this purpose.
Figure 2 shows equivalent input circuits.
_______________________________________________________________________________________
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