Maxim MAX519BMJE 2-wire serial 8-bit dacs with rail-to-rail output Datasheet

19-0393; Rev 0; 5/95
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
____________________________Features
♦
♦
♦
♦
♦
________________________Applications
________________Functional Diagram
Single +5V Supply
Simple 2-Wire Serial Interface
I2C Compatible
Output Buffer Amplifiers Swing Rail-to-Rail
Space-Saving 8-pin DIP/SO Packages
(MAX517/MAX518)
♦ Reference Input Range Includes Both Supply Rails
(MAX517/MAX519)
♦ Power-On Reset Clears All Latches
♦ 4µA Power-Down Mode
______________Ordering Information
TEMP. RANGE
MAX517ACPA
0°C to +70°C
8 Plastic DIP
1
MAX517BCPA
MAX517ACSA
MAX517BCSA
0°C to +70°C
0°C to +70°C
0°C to +70°C
8 Plastic DIP
8 SO
8 SO
1.5
1
1.5
MAX517BC/D
0°C to +70°C
Dice*
1.5
Ordering Information continued at end of data sheet.
*Dice are specified at TA = +25°C, DC parameters only.
**Contact factory for availability and processing to MIL-STD-883.
Minimum Component Analog Systems
Digital Offset/Gain Adjustment
Industrial Process Control
Automatic Test Equipment
Programmable Attenuators
VDD
7
REF
OUTPUT
LATCH 0
DAC0
INPUT
LATCH 1
OUTPUT
LATCH 1
DAC1
8
OUT1 (REF0)
7
VDD
6
AD0
5
AD1
SCL 3
MAX517
MAX518
SDA 4
SCL
SDA
8
8-BIT
SHIFT
REGISTER
ADDRESS
COMPARATOR
DECODE
START/STOP
DETECTOR
OUT1
MAX518
3
4
DIP/SO
( ) ARE FOR MAX517
Pin Configurations continued at end of data sheet.
OUT0
REF
TOP VIEW
GND 2
1
INPUT
LATCH 0
_________________Pin Configurations
OUT0 1
PIN-PACKAGE
TUE
(LSB)
PART
6
AD0
5
AD1
2
GND
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
MAX517/MAX518/MAX519
_______________General Description
The MAX517/MAX518/MAX519 are 8-bit voltage output
digital-to-analog converters (DACs) with a simple 2-wire
serial interface that allows communication between
multiple devices. They operate from a single 5V supply
and their internal precision buffers allow the DAC outputs to swing rail-to-rail.
The MAX517 is a single DAC and the MAX518/MAX519
are dual DACs. The MAX518 uses the supply voltage
as the reference for both DACs. The MAX517 has a reference input for its single DAC and each of the
MAX519’s two DACs has its own reference input.
The MAX517/MAX518/MAX519 feature a serial interface
and internal software protocol, allowing communication
at data rates up to 400kbps. The interface, combined
with the double-buffered input configuration, allows the
DAC registers of the dual devices to be updated individually or simultaneously. In addition, the devices can
be put into a low-power shutdown mode that reduces
supply current to 4µA. Power-on reset ensures the DAC
outputs are at 0V when power is initially applied.
The MAX517/MAX518 are available in space-saving 8pin DIP and SO packages. The MAX519 comes in 16pin DIP and SO packages.
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
ABSOLUTE MAXIMUM RATINGS
VDD to GND ..............................................................-0.3V to +6V
OUT_ ..........................................................-0.3V to (VDD + 0.3V)
REF_ (MAX517, MAX519)...........................-0.3V to (VDD + 0.3V)
AD_.............................................................-0.3V to (VDD + 0.3V)
SCL, SDA to GND.....................................................-0.3V to +6V
Maximum Current into Any Pin............................................50mA
Continuous Power Dissipation (TA = +70°C)
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ...727mW
8-Pin SO (derate 5.88mW/°C above +70°C)................471mW
8-Pin CERDIP (derate 8.00mW/°C above +70°C)........640mW
16-Pin Plastic DIP (derate 10.53mW/°C above +70°C)..842mW
16-Pin Narrow SO (derate 8.70mW/°C above +70°C) ...696mW
16-Pin CERDIP (derate 10.00mW/°C above +70°C) ......800mW
Operating Temperature Ranges
MAX51_C_ _ .......................................................0°C to +70°C
MAX51_E_ _.....................................................-40°C to +85°C
MAX51_MJB ..................................................-55°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°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.
ELECTRICAL CHARACTERISTICS
(VDD = 5V ±10%, VREF_ = 4V (MAX517, MAX519), RL = 10kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted.
Typical values are TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
STATIC ACCURACY
Resolution
8
Total Unadjusted Error (Note 1)
TUE
Differential Nonlinearity (Note 1)
DNL
Zero-Code Error
Zero-Code-Error Supply Rejection
Zero-Code-Error Temperature Coefficient
Full-Scale Error
Full-Scale-Error Supply Rejection
Full-Scale-Error Temperature Coefficient
2
ZCE
Bits
MAX51 _A
±1
MAX51 _B
±1.5
Guaranteed monotonic
Code = 00 hex
Code = 00 hex
18
MAX51 _E
20
MAX51 _BM
20
MAX51 _C
±1
MAX51 _E
±1
MAX51 _BM
±1
Code = 00 hex
Code = FF hex,
MAX518 unloaded
MAX517, MAX519
Code = FF hex
VDD = +5V ±10%
Code = FF hex
±1
MAX51 _C
±10
MAX51 _E
±20
MAX51 _BM
±20
±1
±1
MAX51 _BM
±1
±10
_______________________________________________________________________________________
mV
µV/°C
±18
MAX51 _C
LSB
mV
MAX51 _C
MAX51 _E
LSB
mV
mV
µV/°C
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
(VDD = 5V ±10%, VREF_ = 4V (MAX517, MAX519), RL = 10kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted.
Typical values are TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX UNITS
REFERENCE INPUTS (MAX517, MAX519)
Input Voltage Range
Input Resistance
0
RIN
Code = 55 hex (Note 2)
16
VDD
24
V
kΩ
Input Current
Power-down mode
Input Capacitance
Code = FF hex (Note 3)
30
±10
µA
pF
Channel-to-Channel Isolation
(MAX519)
(Note 4)
-60
dB
AC Feedthrough
(Note 5)
-70
dB
DAC OUTPUTS
Full-Scale Output Voltage
0
Output Load Regulation
Output Leakage Current
VDD
OUT_ = 4V, 0mA to 2.5mA
0.25
MAX51 _C/E, REF_ = VDD
(MAX517, MAX519), code = FF hex,
0µA to 500µA
1.5
MAX51 _M, REF_ = VDD
(MAX517, MAX519), code = FF hex,
0µA to 500µA
2.0
V
LSB
OUT_ = 0V to VDD, power-down mode
±10
µA
DIGITAL INPUTS SCL, SDA
Input High Voltage
VIH
Input Low Voltage
VIL
Input Leakage Current
IIN
Input Hysteresis
0.7VDD
0V ≤ VIN ≤ VDD
VHYST
Input Capacitance
CIN
V
0.3VDD
V
±10
µA
10
pF
0.05VDD
V
(Note 6)
DIGITAL INPUTS AD0, AD1, AD2, AD3
Input High Voltage
VIH
Input Low Voltage
VIL
Input Leakage Current
IIN
2.4
V
0.8
V
VIN = 0V to VDD
±10
µA
ISINK = 3mA
0.4
ISINK = 6mA
0.6
VIN = 0V to VDD
±10
µA
10
pF
DIGITAL OUTPUT SDA (Note 7)
Output Low Voltage
Three-State Leakage Current
Three-State Output Capacitance
VOL
IL
COUT
(Note 6)
V
DYNAMIC PERFORMANCE
MAX51 _C
MAX51 _E
MAX51 _M
2.0
1.4
1.0
Voltage Output Slew Rate
Positive and negative
V/µs
Output Settling Time
To 1/2 LSB, 10kΩ and 100pF load (Note 8)
6
µs
Digital Feedthrough
Code = 00 hex, all digital inputs from 0V to VDD
5
nV-s
_______________________________________________________________________________________
3
MAX517/MAX518/MAX519
ELECTRICAL CHARACTERISTICS (continued)
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 5V ±10%, VREF_ = 4V (MAX517, MAX519), RL = 10kΩ, CL = 100pF, TA = TMIN to TMAX, unless otherwise noted.
Typical values are TA = +25°C.)
PARAMETER
SYMBOL
Digital-Analog Glitch Impulse
Signal to Noise + Distortion
Ratio (MAX517, MAX519)
SINAD
Multiplying Bandwidth
(MAX517, MAX519)
CONDITIONS
MIN
TYP
MAX UNITS
Code 128 to 127
VREF_ = 4Vp-p at 1kHz, VDD = 5V,
Code = FF hex
12
nV-s
87
dB
VREF_ = 4Vp-p, 3dB bandwidth
1
MHz
60
µVRMS
Wideband Amplifier Noise
POWER REQUIREMENTS
Supply Voltage
VDD
Supply Current
IDD
4.5
Normal mode, output(s)
unloaded, all digital inputs
at 0V or VDD
5.5
MAX517C
1.5
3.0
MAX517E/M
1.5
3.5
MAX518C, MAX519C
2.5
5
MAX518E/M, MAX519E/M
2.5
6
4
20
Power-down mode
V
mA
µA
TIMING CHARACTERISTICS
(VDD = 5V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are TA = +25°C.)
PARAMETER
Serial Clock Frequency
Bus Free Time Between a STOP and a
START Condition
Hold Time, (Repeated) Start Condition
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
400
kHz
fSCL
0
tBUF
1.3
µs
tHD, STA
0.6
µs
Low Period of the SCL Clock
tLOW
1.3
µs
High Period of the SCL Clock
tHIGH
0.6
µs
Setup Time for a Repeated START Condition
tSU, STA
0.6
Data Hold Time
tHD, DAT
Data Setup Time
tSU, DAT
(Note 9)
0
µs
0.9
100
µs
ns
Rise Time of Both SDA and SCL Signals, Receiving
tR
(Note 10)
20 + 0.1Cb
300
ns
Fall Time of Both SDA and SCL Signals, Receiving
tF
(Note 10)
20 + 0.1Cb
300
ns
Fall Time of SDA Transmitting (Note 7)
tF
ISINK ≤ 6mA (Note 10)
20 + 0.1Cb
250
ns
400
pF
50
ns
Setup Time for STOP Condition
tSU, STO
Capacitive Load for Each Bus Line
Cb
Pulse Width of Spike Suppressed
tSP
0.6
(Notes 6, 11)
0
µs
Note 1: For the MAX518 (full-scale = VDD) the last three codes are excluded from the TUE and DNL specifications, due to the limited
output swing when loaded with 10kΩ to GND.
Note 2: Input resistance is code dependent. The lowest input resistance occurs at code = 55 hex.
Note 3: Input capacitance is code dependent. The highest input capacitance occurs at code FF hex.
Note 4: VREF_ = 4Vp-p, 10kHz. Channel-to-channel isolation is measured by setting the code of one DAC to FF hex and setting the
code of all other DACs to 00 hex.
Note 5: VREF_ = 4Vp-p, 10kHz, DAC code = 00 hex.
Note 6: Guaranteed by design.
Note 7: I2C compatible mode.
Note 8: Output settling time is measured by taking the code from 00 hex to FF hex, and from FF hex to 00 hex.
Note 9: A master device must provide a hold time of at least 300ns for the SDA signal (referred to VIL of the SCL signal) in order to
bridge the undefined region of SCL’s falling edge.
Note 10: Cb = total capacitance of one bus line in pF. tR and tF measured between 0.3VDD and 0.7VDD.
Note 11: Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.
4
_______________________________________________________________________________________
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
8
4
2
3.5
4.0
0
0.5
MAX518 SUPPLY CURRENT
vs. TEMPERATURE
DAC CODE = 1B HEX
1.5
DAC CODE = FF HEX
1.0
1.5
-55 -35 -15
5
25 45 65
25 45
65 85 105 125
MAX518 SUPPLY CURRENT
vs. DAC CODE
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
VDD = 5.5V
BOTH DACS SET
2.0
1.5
1.0
0
0
-55 -35 -15 5
2.0
0.5
DAC CODE = 00 HEX
0.5
MAX517, MAX519
DAC CODE = 00 HEX
6
VDD = 5.5V
ALL DIGITAL INPUTS to VDD
5
4
3
2
1
0
32
0
85 105 125
64
96
128 160 192 224 256
-55 -35 -15
5
25
45
65
85 105 125
DAC CODE (DECIMAL)
TEMPERATURE (°C)
MAX517/MAX519 SUPPLY CURRENT
vs. REFERENCE VOLTAGE
MAX517/MAX519 REFERENCE VOLTAGE INPUT
FREQUENCY RESPONSE
POSITIVE FULL-SCALE STEP RESPONSE
2.5
VDD = 5V
DAC CODE(S) FF HEX
MAX519
1.0
0
RELATIVE OUTPUT (dB)
2.0
MAX517-08
TEMPERATURE (°C)
MAX517
-4
-12
-16
0 0.5 1
1.5 2
2.5 3 3.5 4
REFERENCE VOLTAGE (V)
4.5 5
OUT0
1V/div
4VP-P SINE
2VP-P SINE
1VP-P SINE
0.5VP-P SINE
-8
0.5
0
MAX517-09
SUPPLY CURRENT (mA)
2.5
2.0
MAX517, DAC CODE = FF HEX
TEMPERATURE (°C)
2.5
SUPPLY CURRENT (mA)
VDD = 5.5V
AD0, AD1 = VDD
3.0
1.0
3.0
MAX517-04
3.5
1.0
OUTPUT SINK CURRENT (mA)
SHUTDOWN SUPPLY CURRENT (µA)
2.5 3.0
MAX517-05
1.5 2.0
MAX519, DAC CODE = FF HEX
1.5
0
0
0.5 1.0
2.0
0.5
OUTPUT SOURCE CURRENT (mA)
SUPPLY CURRENT (mA)
MAX517-02
4
2
0
VDD = 5.5V
REF_ INPUTS = 0.6V
ALL DIGITAL INPUTS to VDD
2.5
6
0
1.5
3.0
MAX517-07
6
VDD = VREF = 5V
DAC CODE = 00 HEX
LOAD to VDD
SUPPLY CURRENT (mA)
8
10
MAX517-01
VDD = VREF = 5V
DAC CODE = FF HEX
LOAD TO AGND
ZERO-CODE ERROR (LSB)
FULL-SCALE ERROR (LSB)
10
MAX517/MAX519 SUPPLY CURRENT
vs. TEMPERATURE
ZERO-CODE ERROR
vs. SINK CURRENT
MAX517-03
FULL-SCALE ERROR vs. SOURCE CURRENT
(VREF = VDD)
MAX517/MAX518/MAX519
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
VDD = 5V
VREF = SINE WAVE
CENTERED AT 2.5V
1k
10k
100k
FREQUENCY (Hz)
1M
10M
1µs/div
OUT0 LOADED WITH 10kΩ II 100pF
REF0 = 4V (MAX517/MAX519)
DAC CODE = 00 HEX to FF HEX
_______________________________________________________________________________________
5
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
______________________________Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
NEGATIVE FULL-SCALE STEP RESPONSE
WORST-CASE 1LSB STEP CHANGE
OUT0
20mV/div
AC COUPLED
OUT0
1V/div
1µs/div
OUT0 LOADED WITH 10kΩ II 100pF
REF0 = 4V (MAX517/MAX519)
DAC CODE = FF HEX to 00 HEX
500ns/div
REF0 = 5V (MAX517/MAX519)
DAC CODE = 80 HEX to 7F HEX
MAX517/MAX519
REFERENCE FEEDTHROUGH AT 1kHz
CLOCK FEEDTHROUGH
A
A
B
B
A = SCL, 400kHz, 5V/div
B = OUT0, 5mV/div
DAC CODE = 7F HEX
REF0 = 5V (MAX517/MAX519)
A = REF0, 1V/div (4VP-P)
B = OUT0, 50µV/div, UNLOADED
FILTER PASSBAND = 100Hz to 10kHz
DAC CODE = 00 HEX
MAX517/MAX519
REFERENCE FEEDTHROUGH AT 10kHz
MAX517/MAX519
REFERENCE FEEDTHROUGH AT 100kHz
A
A
B
A = REF0, 1V/div (4VP-P)
B = OUT0, 50µV/div, UNLOADED
FILTER PASSBAND = 1kHz to 100kHz
DAC CODE = 00 HEX
6
B
A = REF0, 1V/div (4VP-P)
B = OUT0, 50µV/div, UNLOADED
FILTER PASSBAND = 10kHz to 1MHz
DAC CODE = 00 HEX
_______________________________________________________________________________________
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
PIN
NAME
FUNCTION
MAX517
MAX518
MAX519
1
1
1
OUT0
DAC0 Voltage Output
2
2
4
GND
Ground
—
—
5
AD3
Address Input 3; sets IC’s slave address
3
3
6
SCL
Serial Clock Input
4
4
8
SDA
Serial Data Input
—
—
9
AD2
Address Input 2; sets IC’s slave address
5
5
10
AD1
Address Input 1; sets IC’s slave address
6
6
11
AD0
Address Input 0; sets IC’s slave address
7
7
12
VDD
Power Supply, +5V; used as reference for MAX518
—
—
13
REF1
Reference Voltage Input for DAC1
8
—
15
REF0
Reference Voltage Input for DAC0
—
8
16
OUT1
DAC1 Voltage Output
—
—
2, 3, 7, 14
N.C.
No Connect—not internally connected.
_______________Detailed Description
VDD
REF0
(REF1)
Serial Interface
INPUT
LATCH 0
OUTPUT
LATCH 0
DAC0
OUT0
INPUT
LATCH 1
OUTPUT
LATCH 1
DAC1
(OUT1)
MAX519 ONLY
8-BIT
SHIFT
REGISTER
ADDRESS
COMPARATOR
MAX517/MAX519
SCL
SDA
START/STOP
DETECTOR
DECODE
AD0 (AD2)
AD1 (AD3)
GND
( ) ARE FOR MAX519
Figure 1. MAX517/MAX519 Functional Diagram
The MAX517/MAX518/MAX519 use a simple 2-wire
serial interface requiring only two I/O lines (2-wire bus)
of a standard microprocessor (µP) port. Figure 2 shows
the timing diagram for signals on the 2-wire bus.
Figure 3 shows a typical application. The 2-wire bus can
have several devices (in addition to the MAX517/
MAX518/MAX519) attached. The two bus lines (SDA and
SCL) must be high when the bus is not in use. When in
use, the port bits are toggled to generate the appropriate
signals for SDA and SCL. External pull-up resistors are
not required on these lines. The MAX517/MAX518/
MAX519 can be used in applications where pull-up resistors are required (such as in I2C systems) to maintain
compatibility with existing circuitry.
The MAX517/MAX518/MAX519 are receive-only devices
and must be controlled by a bus master device. They
operate at SCL rates up to 400kHz. A master device
sends information to the devices by transmitting their
address over the bus and then transmitting the desired
information. Each transmission consists of a START
condition, the MAX517/MAX518/MAX519’s programmable slave-address, one or more command-byte/output-byte pairs (or a command byte alone, if it is the last
byte in the transmission), and finally, a STOP condition
(Figure 4).
_______________________________________________________________________________________
7
MAX517/MAX518/MAX519
______________________________________________________________Pin Description
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
SDA
tSU, DAT
tBUF
tSU, STA
tHD, STA
tLOW
tSU, STO
tHD, DAT
SCL
tHIGH
tHD, STA
tR
tF
START CONDITION
REPEATED START CONDITION
STOP CONDITION
START CONDITION
Figure 2. Two-Wire Serial Interface Timing Diagram
µC
SDA
DUAL
DAC
SCL
RC
1k
SCL
SDA
AD0
AD1
AD2
AD3
REF0
REF1
+1V
+4V
OUT0
OFFSET ADJUSTMENT
OUT1
GAIN ADJUSTMENT
MAX519
DUAL
DAC
MAX518
SCL
SDA
AD0
AD1
SINGLE
DAC
+5V
SCL
SDA
AD0
AD1
OUT0
BRIGHTNESS ADJUSTMENT
OUT1
CONTRAST ADJUSTMENT
REF0
+2.5V
OUT0
THRESHOLD ADJUSTMENT
MAX517
Figure 3. MAX517/MAX518/MAX519 Application Circuit
8
The address byte and pairs of command and output
bytes are transmitted between the START and STOP conditions. The SDA state is allowed to change only while
SCL is low, with the exception of START and STOP conditions. SDA’s state is sampled, and therefore must remain
stable while SCL is high. Data is transmitted in 8-bit
bytes. Nine clock cycles are required to transfer the data
bits to the MAX517/MAX518/MAX519. Set SDA low during the 9th clock cycle as the MAX517/MAX518/MAX519
pull SDA low during this time. RC (see Figure 3) limits the
current that flows during this time if SDA stays high for
short periods of time.
The START and STOP Conditions
When the bus is not in use, both SCL and SDA must be
high. A bus master signals the beginning of a transmission with a START condition by transitioning SDA from
high to low while SCL is high (Figure 5). When the master has finished communicating with the slave, it issues
a STOP condition by transitioning SDA from low to high
while SCL is high. The bus is then free for another
transmission.
The Slave Address
The MAX517/MAX518/MAX519 each have a 7-bit long
slave address (Figure 6). The first three bits (MSBs) of
the slave address have been factory programmed and
are always 010. In addition, the MAX517 and MAX518
have the next two bits factory programmed to 1s. The
logic state of the address inputs (AD0 and AD1 on the
MAX517/MAX518; AD0, AD1, AD2, and AD3 on the
MAX519) determine the LSB bits of the 7-bit slave
address. These input pins may be connected to VDD or
DGND, or they may be actively driven by TTL or CMOS
logic levels. The MAX517/MAX518 have four possible
slave addresses and therefore a maximum of four of
_______________________________________________________________________________________
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
COMMAND BYTE
MAX517/MAX518/MAX519
SLAVE ADDRESS BYTE
OUTPUT BYTE
SDA
MSB
LSB
ACK
MSB
LSB
ACK
MSB
LSB
ACK
SCL
STOP CONDITION
START CONDITION
Figure 4. A Complete Serial Transmission
R2
R1
R0
RST
SDA
PD
A0/0
X
SDA
MSB
ACK
X
LSB
SCL
SCL
STOP CONDITION
START CONDITION
R2, R1, R0: RESERVED BITS. SET TO 0.
Figure 5. All communications begin with a START condition and
end with a STOP condition, both generated by a bus master.
1
0
1 or
AD3
1 or
AD2
PD: POWER-DOWN BIT. SET TO 1 TO PLACE THE DEVICE IN THE 4µA SHUTDOWN
MODE. SET TO 0 TO RETURN TO THE NORMAL OPERATIONAL STATE.
A0: ADDRESS BIT. DETERMINES WHICH DAC'S INPUT LATCH RECEIVES THE 8 BITS
OF DATA IN THE NEXT BYTE. SET TO 0 FOR MAX517.
SLAVE ADDRESS
0
RST: RESET BIT, SET TO 1 TO RESET ALL DAC REGISTERS.
AD1
AD0
0
ACK
ACK: ACKNOWLEDGE BIT. THE MAX517/MAX518/MAX519 PULLS SDA LOW DURING
THE 9TH CLOCK PULSE.
X: DON’T CARE.
SDA
LSB
Figure 7. Command Byte
SCL
SLAVE ADDRESS BITS AD0, AD1, AD2, AND AD3 CORRESPOND TO THE LOGIC
STATE OF THE ADDRESS INPUT PINS.
Figure 6. Address Byte
these devices may share the bus. The MAX519 has 16
possible slave addresses. The eighth bit (LSB) in the
slave address byte should be low when writing to the
MAX517/MAX518/MAX519.
The MAX517/MAX518/MAX519 monitor the bus continuously, waiting for a START condition followed by their
slave address. When a device recognizes its slave
address, it is ready to accept data.
The Command Byte and Output Byte
A command byte follows the slave address. Figure 7
shows the format for the command byte. A command
byte is usually followed by an output byte unless it is
the last byte in the transmission. If it is the last byte, all
bits except PD (power-down) and RST (reset) are
ignored. If an output byte follows the command byte,
A0 of the command byte indicates the digital address
of the DAC whose input data latch receives the digital
output data. Set this bit to 0 when writing to the
MAX517. The data is transferred to the DAC’s output
latch during the STOP condition following the transmission. This allows both DACs of the MAX518/MAX519 to
be updated simultaneously (Figure 8).
Setting the PD bit high powers down the MAX517/
MAX518/MAX519 following a STOP condition (Figure
9a). If a command byte with PD set high is followed by
an output byte, the addressed DAC’s input latch will be
updated and the data will be transferred to the DAC’s
output latch following the STOP condition (Figure 9b).
_______________________________________________________________________________________
9
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
0 1
1 1
or or
0 AD3 AD2AD1 AD0 0
0
0
0
0
0
0
0
0 0 0
1
1
1
1
1
1
1
1
0
SDA
ADDRESS BYTE
START
CONDITION
COMMAND BYTE
(ADDRESSING DAC0)
ACK
ACK
STOP
DAC0 INPUT LATCH CONDITION
SET TO FULL SCALE
DAC OUTPUT CHANGES HERE:
DAC0 GOES TO FULL SCALE.
OUTPUT BYTE
(FULL SCALE)
ACK
(
)
(
)
Figure 8a. Setting One DAC Output (MAX517/MAX518/MAX519)
0 1
1 1
or or
0 AD3 AD2AD1 AD0 0
0
0
0
0
0
0
0
0 0 0
1
1
1
1
1
1
1
1
0
0 0
0
0
0 0
0
1
0
SDA
ADDRESS BYTE
START
CONDITION
1
1
1
1
1
COMMAND BYTE
(ADDRESSING DAC0)
ACK
ACK
OUTPUT BYTE
(FULL SCALE)
ACK
(
1
1
1
COMMAND BYTE
(ADDRESSING DAC1)
DAC0 INPUT LATCH
SET TO FULL SCALE
ACK
)
0
SDA
ACK
OUTPUT BYTE
STOP
(FULL SCALE)
DAC1 INPUT LATCH CONDITION
SET TO FULL SCALE
DAC OUTPUTS CHANGE HERE:
DAC0 AND DAC1 GO TO FULL SCALE.
(
)
(
)
Figure 8b. Setting Both DAC Outputs (MAX518/MAX519)
(a)
0 1
1 1
or or
0 AD3 AD2 AD1 AD0 0
0
(PD)
0 0 0 0 1
0
X
SDA
ADDRESS BYTE
X
X
COMMAND BYTE
ACK
ACK
STOP
CONDITION
START
CONDITION
(b)
0 1
1 1
or or
0 AD3 AD2 AD1AD0 0 0 0
0
0
0
(PD)
1
0
X
SDA
ADDRESS BYTE
ACK
START
CONDITION
NOTE: X = DON'T CARE
0
1
1
(
DEVICE ENTERS
POWER-DOWN STATE
1
1
1
1
1
1
)
0
X
COMMAND BYTE
(ADDRESSING DAC0)
ACK
OUTPUT BYTE
(FULL SCALE)
(
ACK
STOP
CONDITION
DAC0 INPUT LATCH
SET TO FULL SCALE. DEVICE ENTERS POWER-DOWN STATE.
DAC0 OUTPUT LATCH SET TO FULL SCALE.
)
(
Figure 9. Entering the Power-Down State
10
______________________________________________________________________________________
)
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
(a)
0 1
1 1
or or
0 AD3 AD2 AD1 AD0 0
I2C Compatibility
The MAX517/MAX518/MAX519 are fully compatible
with existing I 2 C systems. SCL and SDA are highimpedance inputs; SDA has an open drain that pulls
the data line low during the 9th clock pulse. Figure 12
shows a typical I2C application.
(PD)
0 0 0 0 0 0
0
X
SDA
ADDRESS BYTE
following output byte is ignored. Subsequent pairs of
command/output bytes overwrite the input latches
(Figure 11b).
All changes made during a transmission affect the
MAX517/MAX518/MAX519’s outputs only when the
transmission ends and a STOP has been recognized.
The R0, R1, and R2 bits are reserved and must be set
to zero.
X
X
COMMAND BYTE
ACK
ACK
STOP
CONDITION
START
CONDITION
(b)
0 1
1 1
or or
0 AD3 AD2AD1 AD0 0
0 0
0
0
(PD)
0
0
0 0
X
SDA
ADDRESS BYTE
0
DEVICE RETURNS TO
NORMAL OPERATION
0
0
0
0
0
0
)
0
X
COMMAND BYTE
(ADDRESSING DAC0)
ACK
START
CONDITION
0
(
ACK
OUTPUT BYTE
STOP
(SET TO 0)
CONDITION
DAC0 INPUT
LATCH SET TO 0.
DEVICE RETURNS TO NORMAL OPERATION.
DAC0 SET TO 0.
ACK
(
NOTE: X = DON'T CARE
)
(
)
Figure 10. Returning to Normal Operation from Power-Down
(a)
0 1
1 1
or or
0 AD3 AD2 AD1AD0 0
0
(RST)
0 0 0 1 0
0
X
SDA
ADDRESS BYTE
(
0 1
1 1
or or
0 AD3 AD2 AD1 AD0 0 0 0
0
ACK
)
ALL INPUT LATCHES
SET TO 0.
(RST)
0 1 0
ADDRESS BYTE
START
CONDITION
NOTE: X = DON'T CARE
ACK
STOP
CONDITION
(
ALL OUTPUTS
SET TO 0.
)
0
X
SDA
X
COMMAND BYTE
ACK
START
CONDITION
(b)
X
X
COMMAND BYTE
(
X
0
X X X X X X X X
"DUMMY"
OUTPUT BYTE
ACK
ALL INPUT LATCHES
SET TO 0.
)
ACK
ADDITIONAL
COMMAND BYTE/
OUTPUT BYTE PAIRS
(
STOP
CONDITION
)
DAC OUTPUTS SET TO 0 UNLESS
CHANGED BY ADDITIONAL COMMAND
BYTE/OUTPUT BYTE PAIRS.
Figure 11. Resetting DAC Outputs
______________________________________________________________________________________
11
MAX517/MAX518/MAX519
Furthermore if the transmission’s last command byte
has PD high, the output latches are updated, but voltage outputs will not reflect the newly entered data
because the DAC enters power-down mode when the
STOP condition is detected. When in power-down, the
DAC outputs float. In this mode, the supply current is a
maximum of 20µA. A command byte with the PD bit low
returns the MAX517/MAX518/MAX519 to normal operation following a STOP condition, with the voltage outputs reflecting the output-latch contents (Figures 10a
and 10b). Because each subsequent command byte
overwrites the previous PD bit, only the last command
byte of a transmission affects the power-down state.
Setting the RST bit high clears the DAC input latches.
The DAC outputs remain unchanged until a STOP condition is detected (Figure 11a). If a reset is issued, the
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
µC
latches with data that has not been transferred to the
output latches (Figure 13). Only the currently addressed
device will recognize a STOP condition and transfer
data to its output latches. If the device is left with data in
its input latches, the data can be transferred to the output latches the next time the device is addressed, as
long as it receives at least one command byte and a
STOP condition.
2
E PROM
XICOR
X24C04
SDA SCL
SCL
SDA
Early STOP Conditions
The addressed device recognizes a STOP condition at
any point in a transmission. If the STOP occurs during a
command byte, all previous uninterrupted command
and output byte pairs are accepted, the interrupted
command byte is ignored, and the transmission ends
(Figure 14a). If the STOP occurs during an output byte,
all previous uninterrupted command and output byte
pairs are accepted, the final command byte’s PD and
RST bits are accepted, the interrupted output byte is
ignored, and the transmission ends (Figure 14b).
DUAL
DAC OUT0
SCL MAX518
OUT1
SDA
AD0
AD1
SINGLE
DAC OUT0
+5V
SCL
SDA
AD0
AD1
Analog Section
MAX517
DAC Operation
The MAX518 and MAX519 contain two matched voltage-output DACs. The MAX517 contains a single DAC.
The DACs are inverted R-2R ladder networks that convert 8-bit digital words into equivalent analog output
voltages in proportion to the applied reference voltages. The MAX518 has both DAC’s reference inputs
connected to VDD. Figure 15 shows a simplified diagram of one DAC.
Figure 12. MAX517/MAX518/MAX519 Used in a Typical I2C
Application Circuit
Additional START Conditions
It is possible to interrupt a transmission to a device with
a new START (repeated start) condition (perhaps
addressing another device), which leaves the input
0 1
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
MAX517/MAX519 Reference Inputs
The MAX517 and MAX519 can be used for multiplying
applications. The reference accepts a 0V to VDD volt-
1
1
1
1
1
1
1
1
0
0
1
0
1
1
0
1
0
0
SDA
ADDRESS BYTE
(DEVICE 0)
START
CONDITION
ACK
COMMAND BYTE
ADDRESSING DAC0
OUTPUT BYTE
(FULL SCALE)
ACK
(
0
0
0
0
0
0
0
0 0
1
1
1
1
1
1
1
1
ADDRESS BYTE
(DEVICE 1)
ACK
DEVICE 0's
DAC0 INPUT LATCH
SET TO FULL SCALE.
)
REPEATED START
CONDITION
0
SDA
COMMAND BYTE
(ADDRESSING DAC0)
ACK
OUTPUT BYTE
(FULL SCALE)
(
ACK
DEVICE 1's DAC0
INPUT LATCH SET
TO FULL SCALE.
)(
STOP
CONDITION
)
ONLY DEVICE 1's DAC0 OUTPUT LATCH SET TO FULL
SCALE. DEVICE 0's OUTPUT LATCH UNCHANGED.
Figure 13. Repeated START Conditions
12
______________________________________________________________________________________
ACK
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
0 1
1 1
or or
0 AD3 AD2 AD1 AD0 0
0
MAX517/MAX518/MAX519
(a)
(RST) (PD)
0 0 0 1 1 0
SDA
ADDRESS BYTE
ACK
START
CONDITION
(b)
0 1
1 1
or or
0 AD3 AD2 AD1 AD0 0 0 0
INTERRUPTED
COMMAND BYTE EARLY
MAX517/MAX518/MAX519's
STOP CONDITION STATE REMAINS UNCHANGED.
(
0
(PD)
0 RST 1 0
0
0
0
1
1
1
0
)
0
X X
SDA
ADDRESS BYTE
ACK
START
CONDITION
COMMAND BYTE
(POWER DOWN)
INTERRUPTED
OUTPUT BYTE
ACK
EARLY
STOP CONDITION
(
MAX517/MAX518/MAX519
POWER DOWN; INPUT LATCH
UNCHANGED IF RST = 0,
DAC OUTPUT(S) RESET IF RST = 1.
)
Figure 14. Early STOP Conditions
Table 1. Unipolar Code Table
DAC CONTENTS
ANALOG OUTPUT
11111111
255
+ VREF (———)
256
10000001
129
+ VREF (———)
256
10000000
128
VREF
+ VREF (———) = ——
256
2
01111111
127
+ VREF (———)
256
00000001
1
+ VREF (———)
256
00000000
0V
R
2R
R
R
OUT_
2R
2R
2R
2R
D0
D5
D6
D7
REF_*
GND
SHOWN FOR ALL 1s ON DAC
*REF = VDD FOR THE MAX518
Figure 15. DAC Simplified Circuit Diagram
age, both DC and AC signals. The voltage at each REF
input sets the full-scale output voltage for its respective
DAC. The reference voltage must be positive. The
DAC’s input impedance is code dependent, with the
lowest value occurring when the input code is 55 hex or
0101 0101, and the maximum value occurring when the
input code is 00 hex. Since the REF input resistance
(RIN) is code dependent, it must be driven by a circuit
with low output impedance (no more than RIN ÷ 2000)
to maintain output linearity. The REF input capacitance
is also code dependent, with the maximum value
occurring at code FF hex (typically 30pF). The output
voltage for any DAC can be represented by a digitally
programmable voltage source as: VOUT = (N x VREF) /
256, where N is the numerical value of the DAC’s binary
input code.
Output Buffer Amplifiers
The DAC voltage outputs are internally buffered precision unity-gain followers that slew up to 1V/µs. The outputs can swing from 0V to VDD. With a 0V to 4V (or 4V
to 0V) output transition, the amplifier outputs typically
settle to 1/2LSB in 6µs when loaded with 10kΩ in parallel with 100pF. The buffer amplifiers are stable with any
combination of resistive loads ≥2kΩ and capacitive
loads ≤300pF.
The MAX517/MAX518/MAX519 are designed for unipolar-output, single-quadrant multiplication where the output voltages and the reference inputs are positive with
respect to AGND. Table 1 shows the unipolar code.
______________________________________________________________________________________
13
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
SYSTEM GND
+5V
OUT1
OUT0
REF0
N.C.
N.C.
N.C.
REF1
GND
0.1µF
VDD
RF
REF_
CF
MAX517
MAX519
Figure 16. PC Board Layout for Minimizing MAX519 Crosstalk
(bottom view)
__________Applications Information
Power-Supply Bypassing and
Ground Management
Bypass VDD with a 0.1µF capacitor, located as close to
VDD and GND as possible. Careful PC board layout
minimizes crosstalk among DAC outputs, reference
inputs, and digital inputs. Figure 16 shows the suggested PC board layout to minimize crosstalk.
When using the MAX518 (or the MAX517/MAX519 with
VDD as the reference), you may want to add a noise filter to the VDD supply (Figure 17) or to the reference
input(s) (Figure 18), especially in noisy environments.
The reference input’s bandwidth exceeds 1MHz for AC
signals, so disturbances on the reference input can
easily affect the DAC output(s).
The maximum input current for a single reference input
is VREF/16kΩ = IREF (max). In Figure 17, choose RF so
that changes in the reference input current will have little effect on the reference voltage. For example, with RF
= 6Ω, the maximum output error due to RF is given by:
6Ω x IREF (max) = 1.9mV or 0.1LSB
In Figure 18, there is a voltage drop across RF that
adds to the TUE. This voltage drop is due to the sum of
the reference input current (VREF/16kΩ maximum), supply current (6mA maximum), and the amplifier output
current (VREF/RLOAD). Choose RF to limit this voltage
drop to an acceptable value. For example, with a 10kΩ
load, you can limit the error due to R F to 0.5LSB
(9.8mV) by selecting RF so that:
RF = VRF / IRF ≤ 9.8mV / (5V / 16kΩ + 6mA +
5V / 10kΩ)
RF ≤ 1.4Ω
14
Figure 17. Reference Filter When Using VDD as a Reference
+5V
RF
CF
VDD
MAX518
Figure 18. VDD Filter When Using VDD as a Reference
______________________________________________________________________________________
0.1µF
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
____________________Chip Topography
TOP VIEW
OUT0
OUT0 1
16 OUT1
N.C. 2
15 REF0
N.C. 3
14 N.C.
GND 4
MAX519
OUT1
(MAX518/MAX519)
REF0
(MAX517/
MAX519)
REF1
(MAX519)
13 REF1
AD3 5
12 VDD
SCL 6
11 AD0
N.C. 7
10 AD1
SDA 8
9
GND
0.135"
(3.429mm)
AD3
(MAX519)
AD2
DIP/SO
V DD
__Ordering Information (continued)
AD0
SCL
TUE
(LSB)
PART
TEMP. RANGE
PIN-PACKAGE
MAX517AEPA
-40°C to +85°C
8 Plastic DIP
1
MAX517BEPA
-40°C to +85°C
8 Plastic DIP
1.5
MAX517AESA
-40°C to +85°C
8 SO
1
MAX517BESA
-40°C to +85°C
8 SO
1.5
MAX517BMJA
-55°C to +125°C
8 CERDIP**
1.5
MAX518ACPA
0°C to +70°C
8 Plastic DIP
1
MAX518BCPA
MAX518ACSA
MAX518BCSA
0°C to +70°C
0°C to +70°C
0°C to +70°C
8 Plastic DIP
8 SO
8 SO
1.5
1
1.5
MAX518BC/D
MAX518AEPA
MAX518BEPA
MAX518AESA
MAX518BESA
MAX518BMJA
MAX519ACPE
MAX519BCPE
MAX519ACSE
MAX519BCSE
MAX519BC/D
MAX519AEPE
MAX519BEPE
MAX519AESE
MAX519BESE
MAX519BMJE
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
-55°C to +125°C
0°C to +70°C
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
-55°C to +125°C
Dice*
8 Plastic DIP
8 Plastic DIP
8 SO
8 SO
8 CERDIP**
16 Plastic DIP
16 Plastic DIP
16 Narrow SO
16 Narrow SO
Dice*
16 Plastic DIP
16 Plastic DIP
16 Narrow SO
16 Narrow SO
16 CERDIP**
1.5
1
1.5
1
1.5
1.5
1
1.5
1
1.5
1.5
1
1.5
1
1.5
1.5
SDA
AD2
(MAX519)
AD1
0.078"
(1.981mm)
TRANSISTOR COUNT: 1797
SUBSTRATE CONNECTED TO VDD
*Dice are specified at TA = +25°C, DC parameters only.
**Contact factory for availability and processing to MIL-STD-883.
______________________________________________________________________________________
15
MAX517/MAX518/MAX519
_____Pin Configurations (continued)
MAX517/MAX518/MAX519
2-Wire Serial 8-Bit DACs with
Rail-to-Rail Outputs
________________________________________________________Package Information
D
E
DIM
E1
A
A1
A2
A3
B
B1
C
D1
E
E1
e
eA
eB
L
A3
A A2
L A1
0° - 15°
C
e
B1
eA
B
eB
D1
Plastic DIP
PLASTIC
DUAL-IN-LINE
PACKAGE
(0.300 in.)
INCHES
MAX
MIN
0.200
–
–
0.015
0.175
0.125
0.080
0.055
0.022
0.016
0.065
0.045
0.012
0.008
0.080
0.005
0.325
0.300
0.310
0.240
–
0.100
–
0.300
0.400
–
0.150
0.115
PKG. DIM PINS
P
P
P
P
P
N
D
D
D
D
D
D
8
14
16
18
20
24
MILLIMETERS
MIN
MAX
–
5.08
0.38
–
3.18
4.45
1.40
2.03
0.41
0.56
1.14
1.65
0.20
0.30
0.13
2.03
7.62
8.26
6.10
7.87
2.54
–
7.62
–
–
10.16
2.92
3.81
INCHES
MIN
MAX
0.348 0.390
0.735 0.765
0.745 0.765
0.885 0.915
1.015 1.045
1.14 1.265
MILLIMETERS
MIN
MAX
8.84
9.91
18.67 19.43
18.92 19.43
22.48 23.24
25.78 26.54
28.96 32.13
21-0043A
DIM
D
0°-8°
A
0.101mm
0.004in.
e
B
A1
E
C
L
Narrow SO
SMALL-OUTLINE
PACKAGE
(0.150 in.)
H
A
A1
B
C
E
e
H
L
INCHES
MAX
MIN
0.069
0.053
0.010
0.004
0.019
0.014
0.010
0.007
0.157
0.150
0.050
0.244
0.228
0.050
0.016
DIM PINS
D
D
D
8
14
16
MILLIMETERS
MIN
MAX
1.35
1.75
0.10
0.25
0.35
0.49
0.19
0.25
3.80
4.00
1.27
5.80
6.20
0.40
1.27
INCHES
MILLIMETERS
MIN MAX
MIN
MAX
0.189 0.197 4.80
5.00
0.337 0.344 8.55
8.75
0.386 0.394 9.80 10.00
21-0041A
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.
16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1995 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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