MAXIM MX7837BN

19-0158; Rev 0; 7/93
Complete, Dual, 12-Bit
Multiplying DACs
The MX7837/MX7847 are dual, 12-bit, multiplying, voltage-output digital-to-analog converters (DACs). Each
DAC has an output amplifier and a feedback resistor.
The output amplifier is capable of developing ±10V
across a 2kΩ load. The amplifier feedback resistor is
internally connected to VOUT on the MX7847. No external trims are required to achieve full 12-bit performance
over the entire operating temperature range.
The MX7847 has a 12-bit parallel data input, whereas
the MX7837 operates with a double-buffered 8-bit-bus
interface that loads data in two write operations. All
logic signals are level triggered and are TTL and CMOS
compatible. Fast timing specifications make these
DACs compatible with most microprocessors.
________________________Applications
Small Component-Count Analog Systems
Digital Offset/Gain Adjustments
Industrial Process Control
Function Generators
____________________________Features
♦ Two 12-Bit Multiplying DACs with Buffered
Voltage Output
♦ Specified with ±12V or ±15V Supplies
♦ No External Adjustments Required
♦ Fast Timing Specifications
♦ 24-Pin DIP and SO Packages
♦ 12-Bit Parallel Interface (MX7847)
8-Bit + 4-Bit Interface (MX7837)
______________Ordering Information
ERROR
(LSB)
PART
TEMP. RANGE
PIN-PACKAGE
MX7837JN
0°C to +70°C
24 Narrow Plastic DIP
±1
MX7837KN
MX7837JR
MX7837KR
MX7837C/D
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
24 Narrow Plastic DIP
24 Wide SO
24 Wide SO
Dice*
±1/2
±1
±1/2
±1
Ordering Information continued on last page.
* Contact factory for availability and processing to MIL-STD-883.
Automatic Test Equipment
Automatic Calibration
Machine and Motion Control Systems
_________Typical Operating Circuits
VDD
Waveform Reconstruction
Synchro Applications
MSB
LSB
INPUT INPUT
LATCH LATCH
4
8
DAC LATCH A
12
_________________Pin Configurations
TOP VIEW
CS 1
24 DB0/DB8
RFBA 2
23 DB1/DB9
VREFA
VREFA 3
22 DB2/DB10
VREFB
VOUTA 4
21 DB3/DB11
AGNDA 5
VDD 6
MX7837
20 DB4
19 DB5
VSS 7
18 DB6
AGNDB 8
17 DB7
VOUTB 9
16 A0
VREFB 10
15 A1
DGND 11
14 LDAC
RFBB 12
VOUTA
DAC A
AGNDA
RFBB
DB0
DB7
LDAC
CS
WR
A0
A1
DAC B
CONTROL
LOGIC
12
DAC LATCH B
8
4
LSB
MSB
INPUT INPUT
LATCH LATCH
VOUTB
AGNDB
MX7837
13 WR
DIP/SO
MX7847 on last page.
RFBA
DGND
VSS
MX7847 on last page.
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
MX7837/MX7847
_______________General Description
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
ABSOLUTE MAXIMUM RATINGS
VDD to DGND, AGNDA, AGNDB ............................-0.3V to +17V
VSS to DGND, AGNDA, AGNDB (Note 1) ..............+0.3V to -17V
VREFA, VREFB to AGNDA, AGNDB .. (VSS - 0.3V) to (VDD + 0.3V)
AGNDA, AGNDB to DGND.........................-0.3V to (VDD + 0.3V)
VOUTA, VOUTB to AGNDA, AGNDB .....(VSS - 0.3V) to (VDD + 0.3V)
RFBA, RFBB to AGNDA, AGNDB .......(VSS - 0.3V) to (VDD + 0.3V)
Digital Inputs to DGND ...............................-0.3V to (VDD + 0.3V)
Continuous Power Dissipation (TA = +70°C)
Narrow Plastic DIP (derate 13.33mW/°C above +70°C)....1067mW
SO (derate 11.76mW/°C above +70°C) .........................941mW
Narrow CERDIP (derate 12.50mW/°C above +70°C) ..1000mW
Operating Temperature Ranges:
MX78_7J_/K_ ........................................................0°C to +70°C
MX78_7A_/B_ .................................................. -40°C to +85°C
MX78_7SQ/TQ ............................................... -55°C to +125°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Note 1: If VSS is open-circuited with VDD and either AGND applied, the VSS pin will float positive exceeding the Absolute Maximum Ratings.
If this possibility exists, a Schottky diode connected between VSS and GND ensures the maximum ratings will be observed.
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.
ELECTRICAL CHARACTERISTICS
(VDD = 11.4V to 16.5V, VSS = -11.4V to -16.5V, AGNDA = AGNDB = DGND = 0V, VREFA = VREFB = +10V, RL = 2kΩ, CL = 100pF,
VOUT connected to RFB (MX7837), TA = TMIN to TMAX, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
STATIC PERFORMANCE (Note 3)
Resolution
CONDITIONS
MIN
N
Relative Accuracy
INL
Differential Nonlinearity
DNL
Zero-Code Offset Error
MAX
12
±1
MX78_7K/B/T
±1/2
Guaranteed monotonic
±1
TA = +25°C
±2
Loaded with all 0s,
MX78_7J/A
tempco =
±5µV/°C typ TA = TMIN to TMAX MX78_7K/B
MX78_7S/T
±4
TA = +25°C
TA = TMIN to TMAX
UNITS
Bits
MX78_7J/A/S
Loaded with all 1s,
tempco = ±2ppm
of FSR/°C typ
Gain Error
TYP
±3
LSB
LSB
mV
±5
MX78_7J/A/S
±5
MX78_7K/B/T
±2
MX78_7J/A/S
±7
MX78_7K/B/T
±4
LSB
REFERENCE INPUTS
VREF Input Resistance
8
VREFA, VREFB Resistance
Matching
10
13
kΩ
±0.5
±3
%
DIGITAL INPUTS
Input High Voltage
VINH
Input Low Voltage
VINL
Input Current
2.4
0.8
Digital inputs at 0V and VDD
Input Capacitance (Note 4)
V
±1
µA
8
pF
ANALOG OUTPUTS
DC Output Impedance
Short-Circuit Current
2
VOUT connected to AGND
0.2
Ω
15
mA
_______________________________________________________________________________________
Complete, Dual, 12-Bit
Multiplying DACs
(VDD = 11.4V to 16.5V, VSS = -11.4V to -16.5V, AGNDA = AGNDB = DGND = 0V, VREFA = VREFB = +10V, RL = 2kΩ, CL = 100pF,
VOUT connected to RFB (MX7837), TA = TMIN to TMAX, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
16.5
V
POWER REQUIREMENTS
VDD Range
VDD
VSS Range
VSS
Positive Supply Current
IDD
Output unloaded
5
ISS
Output unloaded
4
Negative Supply Current
Power-Supply Rejection
AC CHARACTERISTICS
Voltage-Output Settling
Time
Slew Rate
Digital-to Analog Glitch
Impulse
Channel-to-Channel Isolation
(VREFA to VOUTB,
VREFB to VOUTA)
Multiplying Feedthrough
Error
Unity-Gain Small-Signal
Bandwidth
Digital Crosstalk
Output Noise Voltage at
+25°C (0.1Hz to 10Hz)
-11.4
-16.5
V
10
mA
6
mA
∆Gain/∆VDD VDD = 15V ±5%, VREF = -10V
±0.01
∆Gain/∆VSS VSS = -15V ±5%, VREF = 10V
∆Gain/∆VDD VDD = 12V ±5%, VREF = -8.9V
±0.01
∆Gain/∆VSS VSS = -12V ±5%, VREF = 8.9V
±0.01
tS
Settling time to within ±1/2LSB of final DAC value;
DAC latch alternately loaded will all 0s and all 1s
Q
DAC latch alternately loaded with 01…11 and
10…00
VREF = 20p-p, 10kHz sine wave, Alternate DAC
Latch Loaded with all 0s
Full-Power Bandwidth
Total Harmonic Distortion
11.4
THD
VREF_ = 20Vp-p, 10kHz sine wave, latches loaded
with all 0s
VREF = 100mVp-p sine wave, DAC latch loaded
with all 1s
VREF = 20Vp-p Sine wave, DAC latch loaded with
all 1s
VREF = 6VRMS, 1kHz, DAC latch loaded with all 1s
Code transition from all 0s to all 1s; see Typical
Operating Characteristics graphs
Amplifier noise and Johnson noise of RFB
±0.01
% per %
4
µs
7
V/µs
60
nV-s
-95
dB
-90
dB
1
MHz
125
kHz
-88
dB
10
nV-s
2
µVRMS
Note 2: The analog outputs can swing to within 2.5V of the supply rails. Hence, for good linearity towards full-scale, |VREFA| and |VREFB| must
be at least 2.5V lower than VDD and |VSS|. Tests done with supply voltages below ±12.5V are done with VREFA = VREFB = ±8.9V.
Note 3: Static performance tested at VDD = +15V, VSS = -15V. Performance over supplies guaranteed by PSRR test.
Note 4: Guaranteed by design.
_______________________________________________________________________________________
3
MX7837/MX7847
ELECTRICAL CHARACTERISTICS (continued)
TIMING CHARACTERISTICS
(VDD = 11.4V to 16.5V, VSS = -11.4V to -16.5V, AGNDA = AGNDB = DGND = 0V, TA = TMIN to TMAX, unless otherwise noted.) (Note 5)
PARAMETER
SYMBOL
MX78_7J/K/A/B
MIN
MAX
0
CONDITIONS
MX78_7S/T
MIN
MAX
0
UNITS
CS to WR Setup Time
t1
CS to WR Hold Time
t2
0
0
ns
WR Pulse Width
t3
80
80
ns
Data to WR Setup Time
t4
80
80
ns
Data to WR Hold Time
t5
10
10
ns
Address to WR SetupTime
t6
MX7837 only
15
15
ns
Address to WR Hold Time
t7
MX7837 only
15
15
ns
LDAC Pulse Width
t8
MX7837 only
80
80
ns
ns
Note 5: All input signals are specified with tR = tF ≤ 5ns. Logic swing is 0V to 5V.
__________________________________________Typical Operating Characteristics
(TA = +25°C, VDD = 15V, VSS = -15V, RL = 2kΩ, CL = 100pF, unless otherwise noted)
OUTPUT VOLTAGE SWING
vs. RESISTIVE LOAD
NOISE SPECTRAL DENSITY
SMALL-SIGNAL FREQUENCY RESPONSE
5
25
15
10
5
0
-5
200
10
1k
100
-25
10
10k
100
1k
10k
10k
1k
100k
1M
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
MULTIPLYING FEEDTHROUGH ERROR
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (BANDWIDTH = 80kHz)
TOTAL HARMONIC DISTORTION + NOISE
vs. FREQUENCY (BANDWIDTH > 500kHz)
-60
-94
VREFA = 20Vp-p
VREFB = AGNDB
DAC CODE = 00...00
-45
VREF = 6VRMS
DAC CODE = 111...111
-96
VREF = 6VRMS
DAC CODE = 111...111
-65
-70
-50
THD (dB)
-98
-55
-60
-65
-100
-75
-80
-85
-102
-70
-90
-75
-104
-95
-80
-85
-100
-106
1k
10k
100k
FREQUENCY (Hz)
4
100
100k
LOAD RESISTANCE (Ω)
-35
-40
-10
-20
0
0
VREF = 100mVp-p
DAC CODE = 11...111
GAIN = -1
-15
100
THD (dB)
VOUT (Vp-p)
20
VREF = 0V
DAC CODE = 11...111
GAIN = -1
300
GAIN (dB)
NOISE SPECTRAL DENSITY (nV/ Hz)
VREF = 20Vp-p at 1kHz
ATTENUATION (dB)
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
1M
100
1k
FREQUENCY (Hz)
10k
100
1k
10k
FREQUENCY (Hz)
_______________________________________________________________________________________
100k
Complete, Dual, 12-Bit
Multiplying DACs
LARGE-SIGNAL PULSE RESPONSE
SMALL-SIGNAL PULSE RESPONSE
AGNDA
A
AGNDA
A = VOUTA, 50mV/div
TIMEBASE = 2µs/div
VREFA = ±100mV SQUARE WAVE
A
A = VOUTA, 5V/div
TIMEBASE = 2µs/div
VREFA = ±10V SQUARE WAVE
______________________________________________________________Pin Description
PIN
MX7837
MX7847
NAME
FUNCTION
1
–
CS
–
1
CSA
Chip-Select Input for DAC A – active-low logic input
2
–
RFBA
Amplifier Feedback Resistor for DAC A
Chip-Select Input for DAC B – active-low logic input
Chip Select – active-low logic input
–
2
CSB
3
3
VREFA
Reference Input Voltage for DAC A
4
4
VOUTA
Analog Output Voltage from DAC A
5
5
AGNDA
6
6
VDD
Positive Power Supply
7
7
VSS
Negative Power Supply
8
8
AGNDB
9
9
VOUTB
Analog Output Voltage from DAC B
10
10
VREFB
Reference Input Voltage for DAC B
11
11
DGND
Digital Ground
12
–
RFBB
Amplifier Feedback Resistor for DAC B
–
12
DB11
Data Bit 11 (MSB)
13
13
WR
Analog Ground for DAC A
Analog Ground for DAC B
Write Input – active-low logic input (MX7837); positive-edge-triggered input used with
CSA and CSB (MX7847)
14
–
LDAC
–
14-24
DB10-DB0
15
–
A1
Address Input – most significant address input for input latches
Address Input – least significant address input for input latches
16
–
A0
17-20
–
21-24
–
DB7-DB4
DB3/DB11DB0/DB8
Asynchronous Load – DAC input, active-low
Data Bit 10 to Data Bit 0 (LSB)
Data Bit 7 to Data Bit 4
Data Bit 3 to Data Bit 0 (LSB), or Data Bit 11 (MSB) to Data Bit 8
_______________________________________________________________________________________
5
MX7837/MX7847
____________________________Typical Operating Characteristics (continued)
(TA = +25°C, VDD = 15V, VSS = -15V, RL = 2kΩ, CL = 100pF, unless otherwise noted.)
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
VREF
R
R
Interface Logic Information
(MX7847)
R
2R
2R
2R
2R
2R
2R
C
B
A
S9
S8
S0
2R
R/2
VOUT
AGND
SHOWN FOR ALL 1s ON DAC
Figure 2 shows the MX7847 input control logic. The
device contains two independent DACs, each with its
own CS input and a common WR input. CSA and WR
control data loading to the DAC A latch, and CSB and
WR control data loading to the DAC B latch. The latches are edge triggered so that input data is latched to
the respective latch on WR's rising edge. The same
data will be latched to both DACs if CSA and CSB are
low and WR is taken high. Table 1 shows the device
control-logic truth table, and Figure 3 shows the writecycle timing diagram.
Table 1. MX7847 Truth Table
CSA
CSB
X
X
1
No Data Transfer
1
1
X
No Data Transfer
D/A Section
0
1
Data Latched to DAC A
Figure 1 shows a simplified circuit diagram for one of
the DACs and the output amplifier. Using a segmented
scheme, the two MSBs of the 12-bit data word are
decoded to drive the three switches (A to C). The
remaining 10 bits drive the switches (S0 to S9) in a
standard R-2R ladder.
Each switch (A to C) directs 1/4 of the total reference
current, and the remaining current passes through the
R-2R section.
The output amplifier and feedback resistor convert current to voltage as follows: VOUT_ = (-D)(VREF_), where D
is the fractional representation of the digital word. (D
can be set from 0 to 4095/4096.)
The output amplifier is capable of developing ±10V
across a 2kΩ load. It is internally compensated and
settles to 0.01% FSR (1/2LSB) in less than 4µs. VOUT
on the MX7837 is not internally connected to RFB.
1
0
Data Latched to DAC B
0
0
Figure 1. D/A Simplified Circuit Diagram
_______________Detailed Description
1
1
X = Don't Care
WR
Function
Data Latched to Both DACs
0
Data Latched to DAC A
0
Data Latched to DAC B
0
Data Latched to Both DACs
= Rising Edge Triggered
Interface Logic Information
(MX7837)
The MX7837 input loading structure is configured for
interfacing with 8-bit-wide data-bus microprocessors.
Each DAC has two 12-bit latches: an input latch, and a
DAC latch. Each input latch is subdivided into a leastsignificant 8-bit latch and a most-significant 4-bit latch.
The data held in the DAC latches determines the outputs. Figure 4 shows the MX7837 input control logic,
and Figure 5 shows the write-cycle timing diagram.
CSA, CSB
CSA
DAC A LATCH
t1
WR
t3
t2
WR
CSB
DAC B LATCH
t4
DATA
Figure 2. MX7847 Input Control Logic
6
t5
VALID DATA
Figure 3. MX7847 Write-Cycle Timing Diagram
_______________________________________________________________________________________
Complete, Dual, 12-Bit
Multiplying DACs
DAC A LATCH
DAC B LATCH
12
12
CS
WR
4
DAC A
MS
INPUT
LATCH
A0
A1
A0/A1
ADDRESS VALID
t7
t6
CS
4
t1
8
DAC A
LS
INPUT
LATCH
8
t2
t3
WR
t5
t4
DATA
DAC B
MS
INPUT
LATCH
MX7837/MX7847
LDAC
VALID DATA
t8
DAC B
LS
INPUT
LATCH
LDAC
Figure 5. MX7837 Write-Cycle Timing Diagram
8
DB7 DB0
Figure 4. MX7837 Input Control Logic
CS, WR, A0, and A1 control data loading to the input
latches. The eight data inputs accept right-justified
data, which can be loaded to the input latches in any
sequence. If LDAC is held high, loading data to the
input latches will not change the analog output. A0
and A1 determine which input latch will receive the
data when CS and WR are low. Table 2 shows the
control logic truth table.
Table 2. MX7837 Truth Table
CS WR
A1
A0
LDAC
Function
and independent of WR. This is useful in many applications, especially in updating multiple MX7837s simultaneously. However, be careful when exercising LDAC
during a write cycle; if an LDAC operation overlaps a
CS and WR operation, invalid data may be latched to
the output. To avoid this, LDAC must remain low after
CS or WR have returned high for a period equal to or
greater than t8, the minimum LDAC pulse width.
Unipolar Binary Operation
Figure 6 shows DAC A (MX7837/MX7847) connected
for unipolar binary operation. Similar connections
apply for DAC B. When VIN is an AC signal, the circuit
performs 2-quadrant multiplication. Table 3 shows the
code table for this circuit. On the MX7847, the RFB
feedback resistor is internally connected to VOUT.
1
X
X
X
1
No Data Transfer
X
1
X
X
1
No Data Transfer
0
0
0
0
1
DAC A LS Input Latch Transparent
0
0
0
1
1
DAC A MS Input Latch Transparent
0
0
1
0
1
DAC B LS Input Latch Transparent
1111 1111 1111
0
0
1
1
1
1
1
X
X
0
DAC B MS Input Latch Transparent
Updated Simultaneously from
the Respective Input Latches
 4095 
−VIN × 

 4096 
1000 0000 0000
 2048 
1
−VIN × 
 = − VIN
2
 4096 
0000 0000 0001
 1 
−VIN × 

 4096 
0000 0000 0000
0V
Table 3. Unipolar Code Table
DAC Latch Contents
MSB
LSB
X = Don't Care
The LDAC input controls 12-bit data transfer from the
input latches to the DAC latches. When LDAC is taken
low, both DAC latches (thus, both analog outputs) are
updated simultaneously. When LDAC is low, the DAC
latches are transparent; DAC data is latched on the rising edge of LDAC. The LDAC input is asynchronous
Analog Output, VOUT
 V 
Note : 1LSB =  IN 
 4096 
_______________________________________________________________________________________
7
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
Bipolar Operation (4-Quadrant
Multiplication)
Figure 7 shows the MX7837/MX7847 connected for
binary operation. The offset-binary coding is shown in
Table 4. When VIN is an AC signal, the circuit performs
4-quadrant multiplication. R1, R2, and R3 resistors
should be 0.01% ratio matched to maintain gain-error
specifications. On the MX7847, the R FB feedback
resistor is internally connected to VOUT.
Table 4. Bipolar Code Table
DAC Latch Contents
MSB
LSB
Analog Output, VOUT
1111 1111 1111
 2047 
+VIN × 

 2048 
1000 0000 0001
 1 
+VIN × 

 2048 
1000 0000 0000
0V
0111 1111 1111
 1 
−VIN × 

 2048 
0000 0000 0000
 2048 
−VIN × 
 = − VIN
 2048 
__________Applications Information
Ground Management
The use of an uninterrupted ground plane is strongly
recommended. AC or transient voltages between analog and digital grounds (between AGNDA/AGNDB and
DGND) can inject noise into the analog circuitry.
Connect the MX7837/MX7847 AGNDs and DGND
directly to the ground plane or to a star ground to
ensure that they are at the same potential. In complex
systems with separate analog and digital ground
planes, connect two diodes (1N914 or equivalent) in
inverse parallel between the AGND and DGND pins.
Power-Supply Decoupling
To minimize noise, decouple the VDD and VSS lines to
DGND using a 10µF capacitor in parallel with a 0.1µF
ceramic capacitor. Minimize capacitor lead lengths for
best noise rejection.
Operation with Reduced
Power-Supply Voltages
The MX7837/MX7847 are specified for operation with
V DD/V SS = ±11.4V to ±16.5V. However, the output
amplifier requires 2.5V of headroom, so the reference
input should not come within 2.5V of VDD/VSS in order to
maintain accuracy at full scale.
 V 
Note : 1LSB =  IN 
 2048 
VDD
VIN
VREFA
DGND
RFBA*
VOUTA*
DAC A
AGNDA VSS
VSS
VOUT
VDD
VDD
VOUT
VIN
VREFA
MX7837
MX7847
DAC A
VSS
* INTERNALLY CONNECTED ON MX7847
R2
20k
R1
20k
VDD
DGND
AGNDA
R3
10k
RFBA*
VOUTA
MX7837
MX7847 VSS
VSS
Figure 6. Unipolar Binary Operation
8
MAX427
Figure 7. Bipolar Offset Binary Operation
_______________________________________________________________________________________
* INTERNALLY CONNECTED
ON MX7847
Complete, Dual, 12-Bit
Multiplying DACs
____Ordering Information (continued)
PART
TOP VIEW
CSA 1
24 DB0
CSB 2
23 DB1
VREFA 3
22 DB2
VOUTA 4
21 DB3
AGNDA 5
VDD 6
MX7847
20 DB4
19 DB5
VSS 7
18 DB6
AGNDB 8
17 DB7
VOUTB 9
16 DB8
VREFB 10
15 DB9
DGND 11
14 DB10
DB11 12
13 WR
DIP/SO
Typical Operating Circuits (continued)
TEMP. RANGE
PIN-PACKAGE
ERROR
(LSB)
MX7837AN -40°C to +85°C
24 Narrow Plastic DIP
±1
MX7837BN
MX7837AR
MX7837BR
MX7837AQ
MX7837BQ
MX7837SQ
MX7837TQ
MX7847JN
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
-55°C to +125°C
0°C to +70°C
24 Narrow Plastic DIP
24 Wide SO
24 Wide SO
24 Narrow CERDIP
24 Narrow CERDIP
24 Narrow CERDIP
24 Narrow CERDIP
24 Narrow Plastic DIP
±1/2
±1
±1/2
±1
±1/2
±1
±1/2
±1
MX7847KN
MX7847JR
MX7847KR
MX7847C/D
MX7847AN
MX7847BN
MX7847AR
MX7847BR
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
24 Narrow Plastic DIP
24 Wide SO
24 Wide SO
Dice*
24 Narrow Plastic DIP
24 Narrow Plastic DIP
24 Wide SO
24 Wide SO
±1/2
±1
±1/2
±1
±1
±1/2
±1
±1/2
MX7847AQ
MX7847BQ
MX7847SQ
MX7847TQ
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
-55°C to +125°C
24 Narrow CERDIP
24 Narrow CERDIP
24 Narrow CERDIP
24 Narrow CERDIP
±1
±1/2
±1
±1/2
VDD
DAC LATCH A
VREFA
VOUTA
DAC A
VREFB
AGNDA
DB0
DB11
DAC B
WR
CSA
CSB
CONTROL
LOGIC
VOUTB
DAC LATCH B
AGNDB
MX7847
DGND
VSS
_______________________________________________________________________________________
9
MX7837/MX7847
______Pin Configurations (continued)
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
__________________________________________________________Chip Topographies
MX7837
V REFA
R FBA
MX7847
CS DB0/DB8 DB1/DB9 DB2/DB10
V REFA
DB3/
DB11
V OUTA
DB4
DB5
AGNDA
0.250"
(6.35mm)
V DD
V SS
V SS
DB6
DB7
AGNDB
V OUTB
A0
CSB
CSA DB0
DB1 DB2
DB3
V OUTA
DB4
DB5
AGNDA
0.250"
(6.35mm)
V DD
V SS
V SS
AGNDB
DB6
DB7
VOUTB
DB8
A1
VREFB DGND RFBB
WR
LDAC
0.140"
(3.56mm)
TRANSISTOR COUNT: 1240;
SUBSTRATE CONNECTED TO V DD.
10
DB9
VREFB DGND
DB11 WR
DB10
0.140"
(3.56mm)
TRANSISTOR COUNT: 1240;
SUBSTRATE CONNECTED TO V DD.
______________________________________________________________________________________
Complete, Dual, 12-Bit
Multiplying DACs
DIM
A
A1
A2
A3
B
B1
C
D
D1
E
E1
e
eA
eB
L
α
D1
E
E1
D
A2
A
A3
α
A1
C
B1
eA
B
eB
DIM
E
MILLIMETERS
MIN
MAX
–
5.08
0.38
–
3.18
3.81
1.40
2.03
0.41
0.56
1.27
1.65
0.20
0.30
31.37
32.13
1.27
2.03
7.62
8.26
6.10
7.11
2.54 BSC
7.62 BSC
–
10.16
2.92
3.81
0˚
15˚
21-337A
L
e
INCHES
MAX
MIN
0.200
–
–
0.015
0.150
0.125
0.080
0.055
0.022
0.016
0.065
0.050
0.012
0.008
1.265
1.235
0.080
0.050
0.325
0.300
0.280
0.240
0.100 BSC
0.300 BSC
0.400
–
0.150
0.115
15˚
0˚
A
A1
B
C
D
E
e
H
h
L
α
H
24-PIN PLASTIC
DUAL-IN-LINE
(NARROW)
PACKAGE
INCHES
MAX
MIN
0.104
0.093
0.012
0.004
0.019
0.014
0.013
0.009
0.614
0.598
0.299
0.291
0.050 BSC
0.419
0.394
0.030
0.010
0.050
0.016
8˚
0˚
MILLIMETERS
MIN
MAX
2.35
2.65
0.10
0.30
0.35
0.49
0.23
0.32
15.20
15.60
7.40
7.60
1.27 BSC
10.00
10.65
0.25
0.75
0.40
1.27
0˚
8˚
21-338A
D
h x 45˚
α
A
0.127mm
0.004in.
e
B
A1
C
L
24-PIN PLASTIC
SMALL-OUTLINE
PACKAGE
______________________________________________________________________________________
11
MX7837/MX7847
________________________________________________________Package Information
MX7837/MX7847
Complete, Dual, 12-Bit
Multiplying DACs
___________________________________________Package Information (continued)
DIM
S1
S
E1
E
D
A
A
B
B1
C
D
E
E1
e
L
L1
Q
S
S1
α
INCHES
MAX
MIN
0.200
–
0.023
0.014
0.065
0.038
0.015
0.008
1.280
–
0.310
0.220
0.320
0.290
0.100 BSC
0.200
0.125
–
0.150
0.060
0.015
0.098
–
–
0.005
15˚
0˚
MILLIMETERS
MIN
MAX
–
5.08
0.36
0.58
0.97
1.65
0.20
0.38
–
32.51
5.59
7.87
7.37
8.13
2.54 BSC
3.18
5.08
3.81
–
0.38
1.52
–
2.49
0.13
–
0˚
15˚
21-340B
α
Q
L
L1
e
B1
B
C
24-PIN CERAMIC
DUAL-IN-LINE
(NARROW)
PACKAGE
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1993 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.