BB DAC4813AP

DAC
®
DAC4813
481
3
QUAD 12-BIT DIGITAL-TO-ANALOG
CONVERTER (12-bit port interface)
FEATURES
DESCRIPTION
● COMPLETE WITH REFERENCE AND
OUTPUT AMPLIFIERS
DAC4813 is a complete quad 12-bit digital-to-analog
converter with bus interface logic. Each package includes a precision +10V voltage reference, doublebuffered bus interface including a RESET function
and 12-bit D/A converters with voltage-output operational amplifiers.
● 12-BIT PORT INTERFACE
● ANALOG OUTPUT RANGE: ±10V
● MONOTONICITY GUARANTEED OVER
TEMPERATURE
● INTEGRAL LINEARITY
ERROR: ±1/2LSB max
● ±12V to ±15V SUPPLIES
● 28-PIN PLASTIC DIP PACKAGE
The double-buffered interface consists of a 12-bit
input latch and a D/A latch for each D/A converter. A
RESET control allows the D/A outputs to be asynchronously reset to bipolar zero, a feature useful for
power-up reset, system initialization and recalibration.
DAC4813 D/A converters are committed to the ±10V
output range only. Gain and offset are not externally
adjustable.
DAC4813
10V
Reference
D/A 1
D/A 2
DB0 LSB
12
DB11
MSB
VREF OUT
VOUT 1
DAC4813 is available with a integral linearity error of
1/2LSB and 12-bit monotonicity guaranteed over temperature. It is packaged in a 28-pin 0.6in. wide plastic
DIP package and specified over –40oC to +85oC and
0°C to +70°C.
VOUT 2
12-bit
Latches
D/A 3
D/A 4
VOUT 3
VOUT 4
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
®
© 1992 Burr-Brown Corporation
PDS-1148C
1
Printed in U.S.A. May, 1997
DAC4813
SPECIFICATIONS
ELECTRICAL
TA = +25oC, +VCC = +12V or +15V, –VCC = –12V or –15V, unless otherwise noted.
DAC4813AP, JP
PARAMETER
CONDITIONS
INPUTS
DIGITAL INPUTS
MIN
TYP
MAX
UNITS
+5.5
+0.8
V
V
±40
±40
µA
µA
±1/4
±1/2
±0.05
±0.05
±1/2
±1
±0.2
±0.2
LSB
LSB
%
%FSR(4)
±5
±1
±20
±10
ppmFSR/%+VCC
ppmFSR/%–VCC
±5
±5
±1/2
Guaranteed
±30
±15
±3/4
ppm/°C
ppmFSR/°C
LSB
4.5
6
µs
µs
V/µs
LSB
±10
V
mA
Ω
+10.05
V
0.2
±5
Indefinite
±25
mA
Ω
ppm/°C
+15
–15
+16.5
–16.5
V
V
48
24
1080
60
28
1320
mA
mA
mW
–3
+3
V
–40
0
–60
+85
+70
+100
30
°C
°C
°C
°C/W
Over Temperature
Input Code (1)
Logic Levels (2)
VIH (3)
VIL
Logic Input Currents
DB0-DB11, WR, LDAC, RESET,ENX
IIH
IIL
Range
Bipolar Offset Binary
+2
0
VI = +2.7V
VI = +0.4V
TRANSFER CHARACTERISTICS
ACCURACY
Linearity Error
Differential Linearity Error
Gain Error
Bipolar Zero Error (5)
Power Supply Sensitivity
Of Full Scale +VCC
–VCC
DRIFT
Over Specification
Temperature Range
Gain
Bipolar Zero Drift
Linearity Error over Temperature
Monotonicity
DYNAMIC CHARACTERISTICS
SETTLING TIME (6)
Full Scale Range Change
1LSB Output Step (7) At Major Carry
Slew Rate
Crosstalk (8)
OUTPUT
Output Voltage Range
Output Current
Output Impedance
Short Circuit to ACOM Duration
REFERENCE VOLTAGE
Voltage
Source Current Available
for External Loads
Impedance
Temperature Coefficient
Short Circuit to Common Duration
POWER SUPPLY REQUIREMENTS
Voltage: +VCC
–VCC
Current:
To within ±0.012%FSR
of Final Value
5kΩ || 500pF Load
20V Range
2
10
0.2
5kΩ Loads
±VCC ≥ ±11.4V
±5
0.2
Indefinite
at DC
+9.95
+10.00
2
at DC
+11.4
–11.4
No Load
±VCC = ±15V
+VCC
–VCC
Power Dissipation
Potential at DCOM with
Respect to ACOM (9)
TEMPERATURE RANGES
Specification: AP
JP
Storage
Thermal Resistance, θJA,Plastic DIP
NOTES: (1) For Two’s Complement Input Coding invert the MSB with an external logic inverter. (2) Digital inputs are TTL and +5V CMOS compatible over the specification
temperature range. (3) Open DATA input lines will be pulled above +5.5V. See discussion under LOGIC INPUT COMPATIBILITY in the OPERATION section. (4) FSR
means Full Scale Range. For example, for ±10V output, FSR = 20V. (5) Error at input code 800HEX. (6) Maximum represents the 3σ limit. Not 100% tested for this
parameter. (7) For the worst-case code change: 7FFHEX to 800HEX and 800HEX to 7FFHEX. (8) Crosstalk is defined as the change in any output as a result of any other
output being driven from –10V to +10V at rated output current. (9) The maximum voltage at which ACOM and DCOM may be separated without affecting accuracy
specifications.
®
DAC4813
2
TIMING DIAGRAMS
ABSOLUTE MAXIMUM RATINGS
+VCC to ACOM ............................................................................ 0 to +18V
–VCC to ACOM ............................................................................ 0 to –18V
+VCC to –VCC ............................................................................... 0 to +36V
ACOM to DCOM .................................................................................. ±4V
Digital Inputs to DCOM ........................................................... –1V to +VCC
External Voltage applied to BPO Resistor ......................................... ±18V
VREF OUT .............................................................. Indefinite short to ACOM
VOUT ............................................................................ Momentary to ±18V
Lead Temperature, soldering 10s .................................................. +300oC
Max Junction Temperature .............................................................. 165oC
WRITE CYCLE #1
(Load first rank from Data Bus: LDAC = 1)
> 50ns
ENX
> 50ns
DB11–DB0
> 5ns
NOTE: Stresses above those listed under “Absolute Maximum Ratings” may
cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.
WR
> 50ns
PACKAGE/ORDERING INFORMATION
WRITE CYCLE #2
(Load second rank from first rank: ENX = 1)
PRODUCT
> 50ns
LDAC
PACKAGE
DAC4813AP 28-Pin Plastic DBL Wide DIP
DAC4813JP 28-Pin Plastic DBL Wide DIP
> 50ns
PACKAGE
DRAWING
NUMBER(1)
TEMPERATURE
RANGE
215
215
–40°C to +85°C
0°C to +70°C
NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix C of Burr-Brown IC Data Book.
WR
tSETTLING
ELECTROSTATIC
DISCHARGE SENSITIVITY
±1/2LSB
V OUT
Electrostatic discharge can cause damage ranging from performance degradation to complete device failure. Burr-Brown
Corporation recommends that all integrated circuits be handled
and stored using appropriate ESD protection methods.
RESET COMMAND (Bipolar Mode)
ENX, LDAC, WR = Don’t Care
Reset
> 50ns
+10V
tSETTLING
VOUT
0V
±1/2LSB
–10V
TRUTH TABLE
WR
EN1
EN2
EN3
EN4
LDAC
RESET
X
1
X
0
0
0
0
0
0
X
X
1
1
1
1
0
1
0
X
X
1
1
1
0
1
1
0
X
X
1
1
0
1
1
1
0
X
X
1
0
1
1
1
1
0
X
X
1
1
1
1
1
0
0
0
1
1
1
1
1
1
1
1
OPERATION
Reset all D/A Latches
No Operation
No Operation
Load Data into First Rank for D/A 4
Load Data into First Rank for D/A 3
Load Data into First Rank for D/A 2
Load Data into First Rank for D/A 1
Load Second Rank from First Rank, All D/As
All Latches Transparent
“X” = Don’t Care
®
3
DAC4813
PIN DESCRIPTIONS
PIN
NAME
FUNCTION
1
2
3
4
5
6
7
8
9
10
11
12
13
DB11
DB10
DB9
DB8
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
RESET
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
WR
EN1
EN2
EN3
EN4
LDAC
DCOM
–VCC
ACOM
+VCC
VOUT 4
VOUT 3
VOUT 2
VOUT 1
VREF OUT
DATA, MSB, positive true.
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA, LSB.
Resets output of all D/As to bipolar-zero. The D/A remains in this state until overwritten by a LDAC-WR command. RESET
does not reset the input latch. After power–up and reset, input latches will be in an indeterminant state.
Write strobe. Must be low for data transfer to any latch (except RESET).
Enable for 12-bit input data latch of D/A1. NOTE: This logic path is slower than the WR/ path.
Enable for 12-bit input data latch of D/A2. NOTE: This logic path is slower than the WR/ path.
Enable for 12-bit input data latch of D/A3. NOTE: This logic path is slower than the WR /path.
Enable for 12-bit input data latch of D/A4. NOTE: This logic path is slower than the WR/ path.
Load DAC enable. Must be low with WR for data transfer to the D/A latch and simultaneous update of all D/A converters.
Digital common, logic currents return.
Analog supply input, nominally –12V or –15V referred to ACOM.
Analog common, +VCC, –VCC supply return.
Analog supply input, nominally +12V or +15V referred to ACOM.
D/A 4 analog output.
D/A 3 analog output.
D/A 2 analog output.
D/A 1 analog output.
+10V reference output.
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.
®
DAC4813
4
BLOCK DIAGRAM
MSB
DB11
1
WR
14
EN1
15
LSB
DB0
2
3
4
5
6
7
8
9
10
11
12
12
25kΩ
12-Bit Input Latch
25kΩ
12-Bit D/A Latch
0–800µA
12-Bit D/A Converter
50kΩ
27
VOUT 1
26
VOUT 2
25
VOUT 3
24
VOUT 4
12
25kΩ
EN2
12-Bit Input Latch
16
25kΩ
12-Bit D/A Latch
0–800µA
12-Bit D/A Converter
50kΩ
12
25kΩ
EN3
12-Bit Input Latch
17
25kΩ
12-Bit D/A Latch
0–800µA
12-Bit D/A Converter
50kΩ
12
25kΩ
EN4
18
12-Bit Input Latch
LDAC
19
12-Bit D/A Latch
RESET
13
25kΩ
0–800µA
12-Bit D/A Converter
50kΩ
+10V
Reference
28
22
VREF OUT
ACOM
20
23
21
DCOM +VCC –VCC
NOTE: RESET does not reset input latches.
®
5
DAC4813
TYPICAL PERFORMANCE CURVES
POWER SUPPLY REJECTION vs
POWER SUPPLY RIPPLE FREQUENCY
DIGITAL INPUT CURRENT vs INPUT VOLTAGE
1k
WR
12.0
9.6
+VCC
100
7.2
Input Current (µA)
10
–VCC
RESET, LDAC
4.8
ENX
2.4
0
–2.4
–4.8
1
–7.2
DB0-DB11: DAC4813
–9.6
–12.0
0.1
10
100
1k
10k
100k
1M
–2
0
2
CHANGE OF GAIN AND OFFSET ERROR
vs TEMPERATURE
0.8
0
Unipolar
Offset
Gain Error
–0.5
–0.4
–1
Linearity Error (LSB)
∆ Gain Error (%)
0.4
0
0
–0.8
–20
20
60
Temperature (°C)
100
–0.5
000
140
400
800
C00
FFF
Input Code (Hexidecimal)
± FULL SCALE OUTPUT SWING
MAJOR CARRY GLITCH
15
250
VOUT
10
200
150
WR
+5
0
0
100
VOUT (mV)
5
WR (V)
VOUT (V)
8
0.5
∆ Bipolar/Unipolar Offset (%)
(For 10V FSR; Double for 20V FSR)
Bipolar
Offset
–60
6
INTEGRAL LINEARITY ERROR
1
0.5
4
Input Voltage (V)
Frequency (Hz)
–5
50
0
Data =
7FFH
Data = 800H
WR (V)
[Change in FSR]/[Change in Supply Voltage]
(ppm of FSR/ %)
TA = +25°C, V CC = ±15V unless otherwise noted.
Data = 7FFH
+10
0
–10
–15
0
5
10
15
Time (µs)
20
25
–2
2
4
6
Time (µs)
®
DAC4813
0
6
8
10
12
14
TYPICAL PERFORMANCE CURVES (CONT)
TA = +25°C, VCC = ±15V unless otherwise noted.
SETTLING TIME, –10V TO +10V
SETTLING TIME, +10V TO –10V
20
VOUT
20
1LSB = 4.88mV
1LSB = 4.88mV
0
WR
–10
+5
0
–20
–2
0
2
4
6
8
10
0
VOUT
–10
WR
–20
–40
0
VOUT
–2
12
+5
0
2
4
6
8
10
12
WR (V)
VOUT
VOUT
Around +10V (mV)
10
WR (V)
VOUT
Around –10V (mV)
10
14
Time (µs)
Time (µs)
DISCUSSION OF
SPECIFICATIONS
SETTLING TIME
Settling Time is the total time (including slew time) for the
output to settle to within an error band around its final value
after a change in input. Settling times are specified to
±0.01% of Full Scale Range (FSR) for two conditions: one
for a FSR output change of 20V (25kΩ feedback) and one
for a 1LSB change. The 1LSB change is measured at the
Major Carry (7FFHEX to 800HEX, and 800HEX to 7FFHEX), the
input code transition at which worst-case settling time occurs.
LINEARITY ERROR
Linearity error is defined as the deviation of the analog
output from a straight line drawn between the end points
(digital inputs all “1s” and all “0s”). DAC4813 linearity
error is ±1/2LSB max at +25oC.
DIFFERENTIAL LINEARITY ERROR
Differential Linearity Error (DLE) is the deviation from a
1LSB output change from one adjacent state to the next. A
DLE specification of 1/2LSB means that the output step size
can range from 1/2LSB to 3/2LSB when the digital input
code changes from one code word to the adjacent code word
If the DLE is more positive than –1LSB, the D/A is said to
be monotonic.
OPERATION
INTERFACE LOGIC
The bus interface logic of the DAC4813 consists of two
independently addressable latches in two ranks for each
D/A converter. The first rank consists of one 12-bit input
latch which can be loaded directly from a 12- or 16-bit
microprocessor/microcontroller bus. The input latch holds
data temporarily before it is loaded into the second latch, the
D/A latch. This double buffered organization permits simultaneous update of all D/As.
MONOTONICITY
A D/A converter is monotonic if the output either increases
or remains the same for increasing digital input values.
DAC4813 is monotonic over their specification temperature
range –40oC to +85oC.
DRIFT
Gain Drift is a measure of the change in the Full Scale
Range (FSR) output over the specification temperature range.
Gain Drift is expressed in parts per million per degree
Celsius (ppm/oC).
All latches are level-triggered. Data present when the control signals are logic “0” will enter the latch. When the
control signals return to logic “1”, the data is latched.
CAUTION: DAC4813 was designed to use WR as the fast
strobe. WR has a much faster logic path than ENX (or
LDAC). Therefore, if one permanently wires WR to DCOM
and uses only ENX to strobe data into the latches, the DATA
HOLD time will be long, approximately 20ns to 30ns, and
this time will vary considerably in this range from unit to
unit. DATA HOLD time using WR is 5ns max.
Bipolar Zero Drift is measured with a data input of 800HEX.
The D/A is configured for bipolar output. Bipolar Zero Drift
is expressed in parts per million of Full Scale Range per
degree Celsius (ppm of FSR/oC).
®
7
DAC4813
RESET FUNCTION
The Reset function resets only the D/A latch. Therefore,
after a RESET, good data must be written to all the input
latches before an LDAC – WR command is issued. Otherwise, old data or unknown data is present in the input latches
and will be transferred to the D/A latch producing an analog
output value that may be unwanted.
INTERNAL/EXTERNAL REFERENCE USE
DAC4813 contains a +10V ±50mV voltage reference,
VREF OUT. VREF OUT is available to drive external loads sourcing
up to 2mA. The load current should be constant, otherwise
the gain (and bipolar offset, if connected) of the D/A
converters will vary.
Because of the lack of additional pins required for external
reference inputs, VREF OUT is connected internally to all 4
D/A converters. VREF OUT is available for external use on pin
28.
LOGIC INPUT COMPATIBILITY
DAC4813 digital inputs are TTL compatible (1.4V switching level) over the operating range of +VCC. Each input has
low leakage and high input impedance. Thus the inputs are
suitable for being driven by any type of 5V logic. An
equivalent circuit of a digital input is shown in Figure 1.
GAIN AND OFFSET ADJUSTMENTS
DAC4813 has no Gain and Offset Adjustment option.
Open DATA input lines will float to 7V or more. Although
this will not harm the DAC4813, current spikes will occur in
the input lines when a logic 0 is asserted and, in addition, the
speed of the interface will be slower. A digital output driving
a DATA input line of the DAC4813 must not drive, or let
the DATA input float, above +5.5V. Unused DATA inputs
should be connected to DCOM.
INSTALLATION
POWER SUPPLY CONNECTIONS
Power supply decoupling capacitors should be added. Best
settling time performance occurs using a 1 to 10µF tantalum
capacitor at –VCC. Applications with less critical settling
time may be ale to use 0.01µF at –VCC as well as at +VCC.
The capacitors should be located close to the package.
Unused control inputs should be connected to a voltage
greater than +2V but not greater than +5.5V. If this voltage
is not available, the control inputs can be connected to +VCC
through a 100kΩ resistor to limit the input current.
Digital
Input
DAC4813 features separate digital and analog power supply
returns to permit optimum connections for low noise and
high speed performance. It is recommended that both DIGITAL COMMON (DCOM) and ANALOG COMMON
(ACOM) be connected directly to a ground plane under the
package. If a ground place is not used, connect the ACOM
and DCOM pins together close to the package. Since the
reference point for VOUT and VREF OUT is the ACOM pin, it is
also important to connect the load directly to the ACOM pin.
The change in current in the ACOM pin due to an input date
word change from 000HEX to FFFHEX is only 1mA for each
D/A converter.
R
6.8V
10
to
20pF
II
DCOM
DIGITAL INPUT
Data, LDAC, WR, RESET
ENX
DAC4813
RΩ
OUTPUT VOLTAGE SWING
AND RANGE CONNECTIONS
DAC4813 output amplifiers provide a ±10V output swing
while operating on supplies as low as ±12V ±5%.
250
330
FIGURE 1. Equivalent Digital Input Circuit.
DAC4813 is fully committed to ±10V output ranges. Optional ranges are not pin programmable.
INPUT CODING
DAC4813 accepts positive-true binary input codes.
Input coding for bipolar analog outputs is Bipolar Offset
Binary (BOB), where an input code of 000HEX gives a minus
full-scale output, an input of FFFHEX gives an output 1LSB
below positive full scale, and zero occurs for an input code
of 800HEX.
12- AND 16-BIT BUS INTERFACES
DAC4813 data is latched into the input latches of each D/A
by asserting low each ENx individually and transferring the
data from the bus to each input latch by asserting WR low.
All D/A outputs in each package are then updated simultaneously by asserting LDAC and WR low.
DAC4813 can be used with two's complement coding if a
logic inverter is used ahead of the MSB input (DB11).
Be sure to read the CAUTION statement in the LOGIC
INPUT COMPATIBILITY section.
®
DAC4813
8