AD AD5362 8-channel, 16-/14-bit, serial input, voltage output dac Datasheet

8-Channel, 16-/14-Bit,
Serial Input, Voltage Output DAC
AD5362/AD5363
FEATURES
8-channel DAC in 52-lead LQFP and 56-lead LFCSP packages
Guaranteed monotonic to 16/14 bits
Nominal output voltage range of −10 V to +10 V
Multiple output voltage spans available
Thermal shutdown function
Channel monitoring multiplexer
GPIO function
System calibration function allowing user-programmable
offset and gain
Channel grouping and addressing features
Data error checking feature
SPI-compatible serial interface
2.5 V to 5.5 V digital interface
Digital reset (RESET)
Clear function to user-defined SIGGNDx
Simultaneous update of DAC outputs
APPLICATIONS
Instrumentation
Industrial control systems
Level setting in automatic test equipment (ATE)
Variable optical attenuators (VOA)
Optical line cards
FUNCTIONAL BLOCK DIAGRAM
DVCC
TEMP_OUT
PEC
TEMP
SENSOR
CONTROL
REGISTER
VDD
MON_IN1
MUX
8
A/B SELECT 8
REGISTER
n
n
n
MON_OUT
GPIO
GPIO
REGISTER
2
n
n
SYNC
SCLK
n
SERIAL
INTERFACE
X1 REGISTER
M REGISTER
LDAC
C REGISTER
n
X1 REGISTER
M REGISTER
C REGISTER
14
TO
MUX 2s
n
A/B
MUX
n
n
·
·
·
BIN/2SCOMP
SDI
AGND DGND
n = 16 FOR AD5362
n = 14 FOR AD5363
8
VOUT0 TO
VOUT7
6
MON_IN0
VSS
·
·
·
·
·
·
·
·
·
n
n
A/B
MUX
n
X2B REGISTER
MUX
2
n
n
STATE
MACHINE
n
X2A REGISTER
X2B REGISTER
MUX
2
n
C REGISTER
n
n
n
X1 REGISTER
M REGISTER
C REGISTER
·
·
·
·
·
·
n
DAC 3
REGISTER
OUTPUT BUFFER
AND POWERDOWN CONTROL
DAC 3
TO
MUX 2s
n
A/B
MUX
n
n
·
·
·
n
n
VOUT0
VOUT1
VOUT2
VOUT3
SIGGND0
VREF1
n
·
·
·
n
AD5362/
AD5363
M REGISTER
DAC 0
n
A/B SELECT 8
REGISTER
X1 REGISTER
VREF0
·
·
·
·
·
·
n
A/B
MUX
OFS1
REGISTER
n
BUFFER
OFFSET
DAC 1
GROUP 1
BUFFER
X2A REGISTER
X2B REGISTER
MUX
2
n
n
DAC 4
REGISTER
·
·
·
·
·
·
·
·
·
X2A REGISTER
X2B REGISTER
MUX
2
n
n
·
DAC 7
REGISTER
OUTPUT BUFFER
AND POWERDOWN CONTROL
DAC 4
n
DAC 7
·
·
·
OUTPUT BUFFER
AND POWERDOWN CONTROL
VOUT4
VOUT5
VOUT6
VOUT7
SIGGND1
05762-001
n
GROUP 0
OUTPUT BUFFER
AND POWERDOWN CONTROL
n
·
·
·
BUSY
CLR
DAC 0
REGISTER
·
·
·
14
8
BUFFER
OFFSET
DAC 0
BUFFER
X2A REGISTER
SDO
RESET
OFS0
REGISTER
14
Figure 1.
Rev. A
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DOCUMENTATION
AN-0986: Adjusting the Output Range and Span of the AD5362
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EVALUATION KITS & SYMBOLS & FOOTPRINTS
SAMPLE & BUY
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AD5363
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AD5362/AD5363
TABLE OF CONTENTS
Features .............................................................................................. 1
Reset Function ............................................................................ 20
Applications ....................................................................................... 1
Clear Function ............................................................................ 20
Functional Block Diagram .............................................................. 1
BUSY and LDAC Functions...................................................... 20
Revision History ............................................................................... 2
BIN/2SCOMP Pin ...................................................................... 20
General Description ......................................................................... 3
Temperature Sensor ................................................................... 20
Specifications..................................................................................... 4
Monitor Function ....................................................................... 21
AC Characteristics........................................................................ 6
GPIO Pin ..................................................................................... 21
Timing Characteristics ................................................................ 7
Power-Down Mode .................................................................... 21
Absolute Maximum Ratings.......................................................... 10
Thermal Shutdown Function ................................................... 21
ESD Caution ................................................................................ 10
Toggle Mode................................................................................ 21
Pin Configuration and Function Descriptions ........................... 11
Serial Interface ................................................................................ 22
Typical Performance Characteristics ........................................... 13
SPI Write Mode .......................................................................... 22
Terminology .................................................................................... 15
SPI Readback Mode ................................................................... 22
Theory of Operation ...................................................................... 16
Register Update Rates ................................................................ 22
DAC Architecture ....................................................................... 16
Packet Error Checking ............................................................... 23
Channel Groups .......................................................................... 16
Channel Addressing and Special Modes ................................. 23
A/B Registers and Gain/Offset Adjustment............................ 17
Special Function Mode .............................................................. 24
Offset DACs ................................................................................ 17
Applications Information .............................................................. 26
Output Amplifier ........................................................................ 18
Power Supply Decoupling ......................................................... 26
Transfer Function ....................................................................... 18
Power Supply Sequencing ......................................................... 26
Reference Selection .................................................................... 18
Interfacing Examples ................................................................. 26
Calibration ................................................................................... 19
Outline Dimensions ....................................................................... 27
Additional Calibration ............................................................... 19
Ordering Guide .......................................................................... 28
REVISION HISTORY
3/08—Rev. 0 to Rev. A
Added 56-Lead LFCSP_VQ .............................................. Universal
Changes to Table 2 ............................................................................ 4
Added t23 Parameter ......................................................................... 7
Changes to Figure 4 .......................................................................... 8
Changes to Table 6 .......................................................................... 11
Changes to A/B Registers and Gain/Offset Adjustment
Section .............................................................................................. 17
Changes to Calibration Section .................................................... 19
Changes to Reset Function Section and BUSY and LDAC
Functions Section ........................................................................... 20
Changes to Channel Addressing and Special Modes Section .. 23
Updated Outline Dimensions ....................................................... 27
Changes to Ordering Guide .......................................................... 28
1/08—Revision 0: Initial Version
Rev. A | Page 2 of 28
AD5362/AD5363
GENERAL DESCRIPTION
The AD5362/AD5363 contain eight 16-/14-bit DACs in a single
52-lead LQFP package or 56-lead LFCSP package. The devices
provide buffered voltage outputs with a span of 4× the reference
voltage. The gain and offset of each DAC can be independently
trimmed to remove errors. For even greater flexibility, the device
is divided into two groups of four DACs, and the output range
of each group can be independently adjusted by an offset DAC.
The AD5362/AD5363 offer guaranteed operation over a wide
supply range with VSS from −16.5 V to −4.5 V and VDD from 8 V
to 16.5 V. The output amplifier headroom requirement is 1.4 V,
operating with a load current of 1 mA.
The AD5362/AD5363 have a high speed 4-wire serial interface
that is compatible with SPI, QSPI™, MICROWIRE™, and DSP
interface standards and can handle clock speeds of up to
50 MHz. All the outputs can be updated simultaneously by
taking the LDAC input low. Each channel has a programmable
gain and an offset adjust register.
Each DAC output is gained and buffered on chip with respect
to an external SIGGNDx input. The DAC outputs can also be
switched to SIGGNDx via the CLR pin.
Table 1. High Channel Count Bipolar DACs
Model
AD5360
AD5361
AD5362
AD5363
AD5370
AD5371
AD5372
AD5373
AD5378
AD5379
Resolution (Bits)
16
14
16
14
16
14
16
14
14
14
Nominal Output Span
4 × VREF (20 V)
4 × VREF (20 V)
4 × VREF (20 V)
4 × VREF (20 V)
4 × VREF (12 V)
4 × VREF (12 V)
4 × VREF (12 V)
4 × VREF (12 V)
±8.75 V
±8.75 V
Output Channels
16
16
8
8
40
40
32
32
32
40
Rev. A | Page 3 of 28
Linearity Error (LSB)
±4
±1
±4
±1
±4
±1
±4
±1
±3
±3
AD5362/AD5363
SPECIFICATIONS
DVCC = 2.5 V to 5.5 V; VDD = 9 V to 16.5 V; VSS = −16.5 V to −4.5 V; VREF = 5 V; AGND = DGND = SIGGND0 = SIGGND1 = 0 V;
RL = open circuit; gain (M), offset (C), and DAC offset registers at default values; all specifications TMIN to TMAX, unless otherwise noted.
Table 2.
Parameter
ACCURACY
Resolution
Integral Nonlinearity (INL)
Differential Nonlinearity (DNL)
Zero-Scale Error
Full-Scale Error
Gain Error
Zero-Scale Error 2
Full-Scale Error2
Span Error of Offset DAC
VOUTx 3 Temperature Coefficient
DC Crosstalk2
REFERENCE INPUTS (VREF0, VREF1)2
VREFx Input Current
VREFx Range2
SIGGND0 AND SIGGND1 INPUTS2
DC Input Impedance
Input Range
SIGGNDx Gain
OUTPUT CHARACTERISTICS2
Output Voltage Range
Nominal Output Voltage Range
Short-Circuit Current
Load Current
Capacitive Load
DC Output Impedance
MONITOR PIN (MON_OUT)2
Output Impedance
DAC Output at Positive Full Scale
DAC Output at Negative Full Scale
Three-State Leakage Current
Continuous Current Limit
DIGITAL INPUTS
Input High Voltage
Input Low Voltage
Input Current
Input Capacitance2
B Version 1
Unit
Test Conditions/Comments
16
14
±4
±1
±1
±15
±20
0.1
1
1
±75
5
180
Bits
Bits
LSB max
LSB max
LSB max
mV max
mV max
% FSR
LSB typ
LSB typ
mV max
ppm FSR/°C typ
μV max
AD5362
AD5363
AD5362
AD5363
Guaranteed monotonic by design over temperature
Before calibration
Before calibration
Before calibration
After calibration
After calibration
See the Offset DACs section for details
Includes linearity, offset, and gain drift
Typically 20 μV; measured channel at midscale, full-scale
change on any other channel
±10
2/5
μA max
V min/V max
Per input; typically ±30 nA
±2% for specified operation
50
±0.5
0.995/1.005
kΩ min
V min/V max
min/max
Typically 55 kΩ
VSS + 1.4
VDD − 1.4
−10 to +10
15
±1
2200
0.5
V min
V max
V
mA max
mA max
pF max
Ω max
ILOAD = 1 mA
ILOAD = 1 mA
1000
500
100
2
Ω typ
Ω typ
nA typ
mA max
1.7
2.0
0.8
±1
±20
10
V min
V min
V max
μA max
μA max
pF max
Rev. A | Page 4 of 28
VOUTx3 to DVCC, VDD, or VSS
DVCC = 2.5 V to 3.6 V
DVCC = 3.6 V to 5.5 V
DVCC = 2.5 V to 5.5 V
RESET, SYNC, SDI, and SCLK pins
CLR, BIN/2SCOMP, and GPIO pins
AD5362/AD5363
Parameter
DIGITAL OUTPUTS (SDO, BUSY, GPIO, PEC)
Output Low Voltage
Output High Voltage (SDO)
High Impedance Leakage Current
High Impedance Output Capacitance2
TEMPERATURE SENSOR (TEMP_OUT)2
Accuracy
Output Voltage at 25°C
Output Voltage Scale Factor
Output Load Current
Power-On Time
POWER REQUIREMENTS
DVCC
VDD
VSS
Power Supply Sensitivity2
∆Full Scale/∆VDD
∆Full Scale/∆VSS
∆Full Scale/∆DVCC
DICC
IDD
ISS
Power-Down Mode
DICC
IDD
ISS
Power Dissipation
Power Dissipation Unloaded (P)
Junction Temperature 4
B Version 1
Unit
Test Conditions/Comments
0.5
DVCC − 0.5
±5
10
V max
V min
μA max
pF typ
Sinking 200 μA
Sourcing 200 μA
SDO only
±1
±5
1.46
4.4
200
10
°C typ
°C typ
V typ
mV/°C typ
μA max
ms typ
@ 25°C
−40°C < T < +85°C
2.5/5.5
8/16.5
−16.5/−4.5
V min/V max
V min/V max
V min/V max
−75
−75
−90
2
8.5
8.5
dB typ
dB typ
dB typ
mA max
mA max
mA max
5
35
−35
μA typ
μA typ
μA typ
209
130
mW max
°C max
1
Temperature range for B version: −40°C to +85°C. Typical specifications are at 25°C.
Guaranteed by design and characterization; not production tested.
3
VOUTx refers to any of VOUT0 to VOUT7.
4
θJA represents the package thermal impedance.
2
Rev. A | Page 5 of 28
Current source only
To within ±5°C
DVCC = 5.5 V, VIH = DVCC, VIL = GND
Outputs = 0 V and unloaded
Outputs = 0 V and unloaded
Bit 0 in the control register is 1
VSS = −12 V, VDD = 12 V, DVCC = 2.5 V
TJ = TA + PTOTAL × θJA
AD5362/AD5363
AC CHARACTERISTICS
DVCC = 2.5 V; VDD = 15 V; VSS = −15 V; VREF = 5 V; AGND = DGND = SIGGND0 = SIGGND1 = 0 V; CL = 200 pF; RL = 10 kΩ; gain (M),
offset (C), and DAC offset registers at default values; all specifications TMIN to TMAX, unless otherwise noted.
Table 3.
Parameter
DYNAMIC PERFORMANCE1
Output Voltage Settling Time
Slew Rate
Digital-to-Analog Glitch Energy
Glitch Impulse Peak Amplitude
Channel-to-Channel Isolation
DAC-to-DAC Crosstalk
Digital Crosstalk
Digital Feedthrough
Output Noise Spectral Density @ 10 kHz
1
B Version 1
Unit
Test Conditions/Comments
20
30
1
5
10
100
10
0.2
0.02
250
μs typ
μs max
V/μs typ
nV-s typ
mV max
dB typ
nV-s typ
nV-s typ
nV-s typ
nV/√Hz typ
Full-scale change
DAC latch contents alternately loaded with all 0s and all 1s
VREF0, VREF1 = 2 V p-p, 1 kHz
Effect of input bus activity on DAC output under test
VREF0 = VREF1 = 0 V
Guaranteed by design and characterization; not production tested.
Rev. A | Page 6 of 28
AD5362/AD5363
TIMING CHARACTERISTICS
DVCC = 2.5 V to 5.5 V; VDD = 9 V to 16.5 V; VSS = −16.5 V to −8 V; VREF = 5 V; AGND = DGND = SIGGND = 0 V; CL = 200 pF to GND;
RL = open circuit; gain (M), offset (C), and DAC offset registers at default values; all specifications TMIN to TMAX, unless otherwise noted.
Table 4. SPI Interface
Parameter 1, 2, 3
t1
t2
t3
t4
t5
t6
t7
t8
t9 4
t10
t11
t12
t13
t14
t15
t16
t17
t18
t19
t20
t21
t22 5
t23
Limit at TMIN, TMAX
20
8
8
11
20
10
5
5
42
1/1.5
600
20
10
3
0
3
20/30
140
30
400
270
25
80
Unit
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
μs typ/μs max
ns max
ns min
ns min
μs max
ns min
μs max
μs typ/μs max
ns max
ns min
μs max
ns min
ns max
ns max
Description
SCLK cycle time
SCLK high time
SCLK low time
SYNC falling edge to SCLK falling edge setup time
Minimum SYNC high time
24th SCLK falling edge to SYNC rising edge
Data setup time
Data hold time
SYNC rising edge to BUSY falling edge
BUSY pulse width low (single-channel update); see Table 9
Single-channel update cycle time
SYNC rising edge to LDAC falling edge
LDAC pulse width low
BUSY rising edge to DAC output response time
BUSY rising edge to LDAC falling edge
LDAC falling edge to DAC output response time
DAC output settling time
CLR/RESET pulse activation time
RESET pulse width low
RESET time indicated by BUSY low
Minimum SYNC high time in readback mode
SCLK rising edge to SDO valid
RESET rising edge to BUSY falling edge
1
Guaranteed by design and characterization; not production tested.
All input signals are specified with tR = tF = 2 ns (10% to 90% of DVCC) and timed from a voltage level of 1.2 V.
3
See Figure 4 and Figure 5.
4
t9 is measured with the load circuit shown in Figure 2.
5
t22 is measured with the load circuit shown in Figure 3.
2
200µA
IOL
DVCC
VOH (MIN) – VOL (MAX)
2
CL
50pF
200µA
Figure 2. Load Circuit for BUSY Timing Diagram
IOH
Figure 3. Load Circuit for SDO Timing Diagram
Rev. A | Page 7 of 28
05762-003
CL
50pF
VOL
05762-002
TO
OUTPUT
PIN
TO OUTPUT
PIN
RL
2.2k Ω
AD5362/AD5363
t1
SCLK
1
24
2
t3
t4
SYNC
24
t11
t6
t5
t7
SDI
1
t2
t8
DB0
DB23
t9
t10
BUSY
t12
t13
LDAC1
t17
t14
VOUTx1
t15
t13
LDAC2
t17
VOUTx2
t16
CLR
t18
VOUTx
t19
RESET
VOUTx
t18
t20
BUSY
05762-004
t23
1 LDAC ACTIVE DURING BUSY.
2 LDAC ACTIVE AFTER BUSY.
Figure 4. SPI Write Timing
Rev. A | Page 8 of 28
AD5362/AD5363
t22
SCLK
48
t21
SYNC
DB23
DB0
DB23
DB0
NOP CONDITION
INPUT WORD SPECIFIES
REGISTER TO BE READ
DB0
SDO
DB23
DB15
DB0
SELECTED REGISTER DATA CLOCKED OUT
LSB FROM PREVIOUS WRITE
Figure 5. SPI Read Timing
OUTPUT
VOLTAGE
FULL-SCALE
ERROR
+
ZERO-SCALE
ERROR
VMAX
ACTUAL
TRANSFER
FUNCTION
IDEAL
TRANSFER
FUNCTION
0
2N – 1
DAC CODE
n = 16 FOR AD5362
n = 14 FOR AD5363
ZERO-SCALE
ERROR
05762-006
VMIN
Figure 6. DAC Transfer Function
Rev. A | Page 9 of 28
05762-005
SDI
AD5362/AD5363
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted. Transient currents of up to
60 mA do not cause SCR latch-up.
Table 5.
Parameter
VDD to AGND
VSS to AGND
DVCC to DGND
Digital Inputs to DGND
Digital Outputs to DGND
VREF0, VREF1 to AGND
VOUT0 through VOUT7 to AGND
SIGGND0, SIGGND1 to AGND
AGND to DGND
MON_IN0, MON_IN1, MON_OUT
to AGND
Operating Temperature Range (TA)
Industrial (J Version)
Storage Temperature Range
Operating Junction Temperature
(TJ max)
θJA Thermal Impedance
52-Lead LQFP
56-Lead LFCSP
Reflow Soldering
Peak Temperature
Time at Peak Temperature
Rating
−0.3 V to +17 V
−17 V to +0.3 V
−0.3 V to +7 V
−0.3 V to DVCC + 0.3 V
−0.3 V to DVCC + 0.3 V
−0.3 V to +5.5 V
VSS − 0.3 V to VDD + 0.3 V
−1 V to +1 V
−0.3 V to +0.3 V
VSS − 0.3 V to VDD + 0.3 V
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
−40°C to +85°C
−65°C to +150°C
130°C
38°C/W
25°C/W
230°C
10 sec to 40 sec
Rev. A | Page 10 of 28
AD5362/AD5363
56
55
54
53
52
51
50
49
48
47
46
45
44
43
CLR
LDAC
AGND
DGND
DVCC
SDO
PEC
SDI
SCLK
SYNC
DVCC
DGND
NC
NC
AGND
DGND
DVCC
SDO
PEC
SDI
SCLK
SYNC
DVCC
DGND
NC
NC
NC
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
52 51 50 49 48 47 46 45 44 43 42 41 40
39 NC
2
38 SIGGND0
PIN 1
INDICATOR
3
RESET
BIN/2SCOMP
BUSY
GPIO
MON_OUT
MON_IN0
NC
NC
NC
NC
NC
VDD
VSS
VREF1
37 VOUT3
36 VOUT2
4
35 VOUT1
AD5362/
AD5363
6
7
34 VOUT0
TOP VIEW
(Not to Scale)
8
9
33 TEMP_OUT
32 MON_IN1
31 VREF0
10
30 NC
11
12
29 VSS
28 VDD
13
27 NC
05762-007
NC
VOUT4
VOUT5
VOUT6
VOUT7
SIGGND1
NC
NC
NC
NC
NC
NC
NC
AD5362/
AD5363
TOP VIEW
(Not to Scale)
42
41
40
39
38
37
36
35
34
33
32
31
30
29
NC
NC
SIGGND0
VOUT3
VOUT2
VOUT1
VOUT0
TEMP_OUT
MON_IN1
VREF0
NC
NC
VSS
VDD
NC = NO CONNECT
14 15 16 17 18 19 20 21 22 23 24 25 26
NC = NO CONNECT
PIN 1
INDICATOR
15
16
17
18
19
20
21
22
23
24
25
26
27
28
5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Figure 7. 52-Lead LQFP Pin Configuration
05762-025
1
NC
NC
VOUT4
VOUT5
VOUT6
VOUT7
SIGGND1
NC
NC
NC
NC
NC
NC
NC
LDAC
CLR
RESET
BIN/2SCOMP
BUSY
GPIO
MON_OUT
MON_IN0
NC
NC
VDD
VSS
VREF1
Figure 8. 56-Lead LFCSP Pin Configuration
Table 6. Pin Function Descriptions
LQFP
1
Pin No.
LFCSP
55
Mnemonic
LDAC
2
56
CLR
3
4
1
2
RESET
BIN/2SCOMP
5
3
BUSY
6
4
GPIO
7
5
MON_OUT
8, 32
6, 34
9, 10, 14, 20 to
27, 30, 39 to 42
11, 28
7 to 11, 15, 16,
22 to 28, 31, 32,
41 to 44
12, 29
MON_IN0,
MON_IN1
NC
12, 29
13, 30
VSS
13
34 to 37, 15 to 18
14
36 to 39, 17 to 20
VREF1
VOUT0 to VOUT7
19
21
SIGGND1
31
33
VREF0
VDD
Description
Load DAC Logic Input (Active Low). See the BUSY and LDAC Functions section
for more information.
Asynchronous Clear Input (Level Sensitive, Active Low). See the Clear Function
section for more information.
Digital Reset Input.
Data Format Digital Input. Connecting this pin to DGND selects offset binary.
Setting this pin to 1 selects twos complement. This input has a weak pull-down.
Digital Input/Open-Drain Output. BUSY is open drain when it is an output. See
the BUSY and LDAC Functions section for more information.
Digital I/O Pin. This pin can be configured as an input or output that can be
read back or programmed high or low via the serial interface. When configured
as an input, this pin has a weak pull-down.
Analog Multiplexer Output. Any DAC output, the MON_IN0 input, or the
MON_IN1 input can be routed to this output for monitoring.
Analog Multiplexer Inputs. Can be routed to MON_OUT.
No Connect.
Positive Analog Power Supply; 9 V to 16.5 V for specified performance. These
pins should be decoupled with 0.1 μF ceramic capacitors and 10 μF capacitors.
Negative Analog Power Supply; −16.5 V to −8 V for specified performance.
These pins should be decoupled with 0.1 μF ceramic capacitors and 10 μF
capacitors.
Reference Input for DAC 4 to DAC 7. This reference voltage is referred to AGND.
DAC Outputs. Buffered analog outputs for each of the eight DAC channels.
Each analog output is capable of driving an output load of 10 kΩ to ground.
Typical output impedance of these amplifiers is 0.5 Ω.
Reference Ground for DAC 4 to DAC 7. VOUT4 to VOUT7 are referenced to this
voltage.
Reference Input for DAC 0 to DAC 3. This reference voltage is referred to AGND.
Rev. A | Page 11 of 28
AD5362/AD5363
LQFP
33
Pin No.
LFCSP
35
Mnemonic
TEMP_OUT
38
40
SIGGND0
43, 51
45, 53
DGND
44, 50
46, 52
DVCC
45
47
SYNC
46
48
SCLK
47
49
SDI
48
50
PEC
49
51
SDO
52
54
AGND
Exposed Paddle
EP
Description
Provides an output voltage proportional to the chip temperature, typically
1.46 V at 25°C with an output variation of 4.4 mV/°C.
Reference Ground for DAC 0 to DAC 3. VOUT0 to VOUT3 are referenced to this
voltage.
Ground for All Digital Circuitry. Both DGND pins should be connected to the
DGND plane.
Logic Power Supply; 2.5 V to 5.5 V. These pins should be decoupled with 0.1 μF
ceramic capacitors and 10 μF capacitors.
Active Low or SYNC Input for SPI Interface. This is the frame synchronization
signal for the SPI serial interface. See Figure 4, Figure 5, and the Serial Interface
section for more details.
Serial Clock Input for SPI Interface. See Figure 4, Figure 5, and the Serial Interface
section for more details.
Serial Data Input for SPI Interface. See Figure 4, Figure 5, and the Serial Interface
section for more details.
Packet Error Check Output. This is an open-drain output with a 50 kΩ pull-up
that goes low if the packet error check fails.
Serial Data Output for SPI Interface. See Figure 4, Figure 5, and the Serial
Interface section for more details.
Ground for All Analog Circuitry. The AGND pin should be connected to the
AGND plane.
Exposed Paddle. Connect to VSS.
Rev. A | Page 12 of 28
AD5362/AD5363
TYPICAL PERFORMANCE CHARACTERISTICS
0.0050
2
0.0025
AMPLITUDE (V)
0
0
16384
32768
65535
49152
–0.0050
05762-008
0
DAC CODE
0
1
1.0
VDD = +15V
VSS = –15V
DVCC = +5V
VREF = +3V
0.5
DNL (LSB)
0.5
INL ERROR (LSB)
5
4
Figure 12. Digital Crosstalk
1.0
0
0
–0.5
–0.5
20
40
05762-009
–1.0
0
80
60
TEMPERATURE (°C)
0
16384
0
32768
65535
49152
DAC CODE
Figure 10. Typical INL Error vs. Temperature
Figure 13. Typical AD5362 DNL Plot
600
TA = 25°C
VSS = –15V
VDD = +15V
VREF = +4.096V
OUTPUT NOISE (nV/√Hz)
500
–0.01
400
300
200
–0.02
0
2
4
6
8
TIME (µs)
10
0
0
1
2
3
4
FREQUENCY (Hz)
Figure 14. Output Noise Spectral Density
Figure 11. Analog Crosstalk Due to LDAC
Rev. A | Page 13 of 28
5
05762-013
100
05762-010
AMPLITUDE (V)
3
TIME (µs)
Figure 9. Typical AD5362 INL Plot
–1.0
2
05762-011
–0.0025
–1
05762-012
INL (LSB)
1
–2
TA = 25°C
VSS = –15V
VDD = +15V
VREF = +4.096V
AD5362/AD5363
0.50
14
VSS = –12V
VDD = +12V
VREF = +3V
12
NUMBER OF UNITS
DICC (mA)
0.45
DVCC = +5.5V
0.40
DVCC = 5V
TA = 25°C
DVCC = +3.6V
0.35
DVCC = +2.5V
10
8
6
4
0.30
–20
0
20
40
80
60
TEMPERATURE (°C)
05762-014
0
0.25
–40
0.30
Figure 15. DICC vs. Temperature
0.35
0.45
0.40
DICC (mA)
05762-017
2
0.50
Figure 18. Typical DICC Distribution
2.0
6.5
1.9
IDD
1.8
1.7
VOLTAGE (V)
IDD/ISS (mA)
6.0
5.5
ISS
1.6
1.5
1.4
1.3
5.0
1.2
VSS = –12V
VDD = +12V
VREF = +3V
20
40
80
60
TEMPERATURE (°C)
1.0
–40
20
35
50
65
80
–1.0
1.0
VOUTx – MON_OUT (V)
FULL-SCALE
10
8
6
4
0.5
0
MIDSCALE
ZERO-SCALE
–0.5
2
0
5.8
6.0
6.2
IDD (mA)
6.4
6.6
05762-016
NUMBER OF UNITS
5
Figure 19. TEMP_OUT Voltage vs. Temperature
VSS = –15V
VDD = +15V
TA = 25°C
12
–10
TEMPERATURE (°C)
Figure 16. IDD/ISS vs. Temperature
14
–25
05762-018
0
05762-019
–20
05762-015
4.5
–40
1.1
–1.0
–1.0
–0.5
0
0.5
MON_OUT CURRENT (mA)
Figure 17. Typical IDD Distribution
Figure 20. VOUTx MON_OUT Error vs. MON_OUT Current
Rev. A | Page 14 of 28
AD5362/AD5363
TERMINOLOGY
Integral Nonlinearity (INL)
Integral nonlinearity, or endpoint linearity, is a measure of
the maximum deviation from a straight line passing through
the endpoints of the DAC transfer function. It is measured
after adjusting for zero-scale error and full-scale error and is
expressed in least significant bits (LSB).
Differential Nonlinearity (DNL)
Differential nonlinearity is the difference between the measured
change and the ideal 1 LSB change between any two adjacent
codes. A specified differential nonlinearity of 1 LSB maximum
ensures monotonicity.
Zero-Scale Error
Zero-scale error is the error in the DAC output voltage when
all 0s are loaded into the DAC register. Zero-scale error is a
measure of the difference between VOUT (actual) and VOUT
(ideal), expressed in millivolts, when the channel is at its minimum value. Zero-scale error is mainly due to offsets in the
output amplifier.
Full-Scale Error
Full-scale error is the error in the DAC output voltage when
all 1s are loaded into the DAC register. Full-scale error is a
measure of the difference between VOUT (actual) and VOUT
(ideal), expressed in millivolts, when the channel is at its maximum value. Full-scale error does not include zero-scale error.
Gain Error
Gain error is the difference between full-scale error and
zero-scale error. It is expressed as a percentage of the fullscale range (FSR).
Output Voltage Settling Time
Output voltage settling time is the amount of time it takes for
the output of a DAC to settle to a specified level for a full-scale
input change.
Digital-to-Analog Glitch Energy
Digital-to-analog glitch energy is the amount of energy that is
injected into the analog output at the major code transition. It is
specified as the area of the glitch in nV-s. It is measured by
toggling the DAC register data between 0x7FFF and 0x8000
(AD5362) or 0x1FFF and 0x2000 (AD5363).
Channel-to-Channel Isolation
Channel-to-channel isolation refers to the proportion of input
signal from one DAC reference input that appears at the output
of another DAC operating from another reference. It is
expressed in decibels and measured at midscale.
DAC-to-DAC Crosstalk
DAC-to-DAC crosstalk is the glitch impulse that appears at
the output of one converter due to both the digital change
and subsequent analog output change at another converter.
It is specified in nV-s.
Digital Crosstalk
Digital crosstalk is defined as the glitch impulse transferred to
the output of one converter due to a change in the DAC register
code of another converter. It is specified in nV-s.
Digital Feedthrough
When the device is not selected, high frequency logic activity
on the digital inputs of the device can be capacitively coupled
both across and through the device to appear as noise on the
VOUT pins. It can also be coupled along the supply and ground
lines. This noise is digital feedthrough.
Gain Error = Full-Scale Error − Zero-Scale Error
VOUT Temperature Coefficient
The VOUT temperature coefficient includes output error
contributions from linearity, offset, and gain drift.
DC Output Impedance
DC output impedance is the effective output source resistance.
It is dominated by package lead resistance.
Output Noise Spectral Density
Output noise spectral density is a measure of internally
generated random noise. Random noise is characterized as a
spectral density (voltage per √Hz). It is measured by loading
all DACs to midscale and measuring noise at the output. It is
measured in nV/√Hz.
DC Crosstalk
The DAC outputs are buffered by op amps that share common
VDD and VSS power supplies. If the dc load current changes in
one channel (due to an update), this change can result in a
further dc change in one or more channel outputs. This effect is
more significant at high load currents and is reduced as the load
currents are reduced. With high impedance loads, the effect is
virtually immeasurable. Multiple VDD and VSS terminals are
provided to minimize dc crosstalk.
Rev. A | Page 15 of 28
AD5362/AD5363
THEORY OF OPERATION
DAC ARCHITECTURE
The AD5362/AD5363 contain eight DAC channels and eight
output amplifiers in a single package. The architecture of a
single DAC channel consists of a 16-bit (AD5362) or 14-bit
(AD5363) resistor-string DAC followed by an output buffer
amplifier. The resistor-string section is simply a string of resistors,
of equal value, from VREF0 or VREF1 to AGND. This type of
architecture guarantees DAC monotonicity. The 16-bit (AD5362)
or 14-bit (AD5363) binary digital code loaded to the DAC
register determines at which node on the string the voltage is
tapped off before being fed into the output amplifier. The output
amplifier multiplies the DAC output voltage by 4. The nominal
output span is 12 V with a 3 V reference and 20 V with a 5 V
reference.
CHANNEL GROUPS
The eight DAC channels of the AD5362/AD5363 are arranged
into two groups of four channels. The four DACs of Group 0
derive their reference voltage from VREF0. The four DACs of
Group 1 derive their reference voltage from VREF1. Each group
has its own signal ground pin.
Table 7. AD5362/AD5363 Registers
Register Name
X1A (Group) (Channel)
X1B (Group) (Channel)
M (Group) (Channel)
C (Group) (Channel)
X2A (Group) (Channel)
Word Length in Bits
16 (14)
16 (14)
16 (14)
16 (14)
16 (14)
X2B (Group) (Channel)
16 (14)
DAC (Group) (Channel)
OFS0
OFS1
Control
14
14
5
Monitor
6
GPIO
2
A/B Select 0
8
A/B Select 1
8
Description
Input Data Register A, one for each DAC channel.
Input Data Register B, one for each DAC channel.
Gain trim registers, one for each DAC channel.
Offset trim registers, one for each DAC channel.
Output Data Register A, one for each DAC channel. These registers store the final,
calibrated DAC data after gain and offset trimming. They are not readable or directly
writable.
Output Data Register B, one for each DAC channel. These registers store the final,
calibrated DAC data after gain and offset trimming. They are not readable or directly
writable.
Data registers from which the DACs take their final input data. The DAC registers are
updated from the X2A or X2B registers. They are not readable or directly writable.
Offset DAC 0 data register: sets offset for Group 0.
Offset DAC 1 data register: sets offset for Group 1.
Bit 4 = overtemperature indicator.
Bit 3 = PEC error flag.
Bit 2 = A/B select.
Bit 1 = thermal shutdown.
Bit 0 = software power-down.
Bit 5 = monitor enable.
Bit 4 = monitor DACs or monitor MON_INx pin.
Bit 3 to Bit 0 = monitor selection control.
Bit 1 = GPIO configuration.
Bit 0 = GPIO data.
Bits [3:0] in this register determine whether a DAC in Group 0 takes its data from
Register X2A or Register X2B (0 = X2A, 1 = X2B).
Bits [3:0] in this register determine whether a DAC in Group 1 takes its data from
Register X2A or Register X2B (0 = X2A, 1 = X2B).
Table 8. AD5362/AD5363 Input Register Default Values
Register Name
X1A, X1B
M
C
OFS0, OFS1
Control
A/B Select 0 and A/B Select 1
AD5362 Default Value
0x8000
0xFFFF
0x8000
0x2000
0x00
0x00
Rev. A | Page 16 of 28
AD5363 Default Value
0x2000
0x3FFF
0x2000
0x2000
0x00
0x00
AD5362/AD5363
X1A
REGISTER
X2A
REGISTER
MUX
X1B
REGISTER
MUX
X2B
REGISTER
DAC
REGISTER
DAC
C
REGISTER
05762-020
M
REGISTER
Figure 21. Data Registers Associated with Each DAC Channel
Each DAC channel also has a gain (M) register and an offset (C)
register, which allow trimming out of the gain and offset errors
of the entire signal chain. Data from the X1A register is operated
on by a digital multiplier and adder controlled by the contents of
the M and C registers. The calibrated DAC data is then stored in
the X2A register. Similarly, data from the X1B register is operated
on by the multiplier and adder and stored in the X2B register.
Although a multiplier and an adder symbol are shown in Figure 21
for each channel, there is only one multiplier and one adder in
the device, which are shared among all channels. This has implications for the update speed when several channels are updated
at once, as described in the Register Update Rates section.
Each time data is written to the X1A register, or to the M or C
register with the A/B control bit set to 0, the X2A data is recalculated and the X2A register is automatically updated. Similarly,
X2B is updated each time data is written to X1B, or to M or C
with A/B set to 1. The X2A and X2B registers are not readable
or directly writable by the user.
Data output from the X2A and X2B registers is routed to the
final DAC register by a multiplexer. A 4-bit A/B select register
associated with each group of four DACs controls whether each
individual DAC takes its data from the X2A or X2B register. If a
bit in this register is 0, the DAC takes its data from the X2A
register; if 1, the DAC takes its data from the X2B register.
OFFSET DACS
In addition to the gain and offset trim for each DAC, there are
two 14-bit offset DACs, one for Group 0 and one for Group 1.
These allow the output range of all DACs connected to them to
be offset within a defined range. Thus, subject to the limitations
of headroom, it is possible to set the output range of Group 0 or
Group 1 to be unipolar positive, unipolar negative, or bipolar,
either symmetrical or asymmetrical about 0 V. The DACs in the
AD5362/AD5363 are factory trimmed with the offset DACs set
at their default values. This gives the best offset and gain performance for the default output range and span.
When the output range is adjusted by changing the value of the
offset DAC, an extra offset is introduced due to the gain error of
the offset DAC. The amount of offset is dependent on the magnitude of the reference and how much the offset DAC moves
from its default value. See the Specifications section for this
offset. The worst-case offset occurs when the offset DAC is at
positive or negative full scale. This value can be added to the
offset present in the main DAC channel to give an indication of
the overall offset for that channel. In most cases, the offset can
be removed by programming the C register of the channel with
an appropriate value. The extra offset caused by the offset DAC
needs to be taken into account only when the offset DAC is
changed from its default value. Figure 22 shows the allowable
code range that can be loaded to the offset DAC, depending on
the reference value used. Thus, for a 5 V reference, the offset
DAC should not be programmed with a value greater than 8192
(0x2000).
5
RESERVED
4
Note that because there are eight bits in two registers, it is possible
to set up, on a per-channel basis, whether each DAC takes its
data from the X2A or X2B register. A global command is also
provided that sets all bits in the A/B select registers to 0 or to 1.
3
2
1
0
0
4096
8192
OFFSET DAC CODE
12288
Figure 22. Offset DAC Code Range
Rev. A | Page 17 of 28
16383
05762-021
Each DAC channel has seven data registers. The actual DAC
data-word can be written to either the X1A or X1B input
register, depending on the setting of the A/B bit in the control
register. If the A/B bit is 0, data is written to the X1A register.
If the A/B bit is 1, data is written to the X1B register. Note that
this single bit is a global control and affects every DAC channel
in the device. It is not possible to set up the device on a perchannel basis so that some writes are to X1A registers and some
writes are to X1B registers.
All DACs in the AD5362/AD5363 can be updated simultaneously by taking LDAC low when each DAC register is updated
from either its X2A or X2B register, depending on the setting of
the A/B select registers. The DAC register is not readable or
directly writable by the user. LDAC can be permanently tied
low, and the DAC output is updated whenever new data appears
in the appropriate DAC register.
VREF (V)
A/B REGISTERS AND GAIN/OFFSET ADJUSTMENT
AD5362/AD5363
OUTPUT AMPLIFIER
Because the output amplifiers can swing to 1.4 V below the
positive supply and 1.4 V above the negative supply, this limits
how much the output can be offset for a given reference voltage.
For example, it is not possible to have a unipolar output range
of 20 V, because the maximum supply voltage is ±16.5 V.
The input code is the value in the X1A or X1B register that is
applied to the DAC (X1A, X1B default code = 8192).
DAC_CODE = INPUT_CODE × (M + 1)/214 + C − 213
where:
M = code in gain register − default code = 214 – 1.
C = code in offset register − default code = 213.
OUTPUT
R5
60kΩ
R6
10kΩ
S2
CLR
CLR
R1
20kΩ
R3
20kΩ
AD5363 Transfer Function
S1
DAC
CHANNEL
R4
60kΩ
offset DAC is 8192 (0x2000). With a 5 V reference, this gives
a span of −10 V to +10 V.
R2
20kΩ
The DAC output voltage is calculated as follows:
S3
CLR
VOUT = 4 × VREF × (DAC_CODE − OFFSET_CODE)/
214 + VSIGGND
SIGGNDx
05762-022
SIGGNDx
OFFSET
DAC
Figure 23. Output Amplifier and Offset DAC
Figure 23 shows details of a DAC output amplifier and its connections to the offset DAC. On power-up, S1 is open, disconnecting
the amplifier from the output. S3 is closed, so the output is pulled
to SIGGNDx (R1 and R2 are greater than R6). S2 is also closed to
prevent the output amplifier from being open-loop. If CLR is low at
power-up, the output remains in this condition until CLR is taken
high. The DAC registers can be programmed, and the outputs
assume the programmed values when CLR is taken high. Even if
CLR is high at power-up, the output remains in this condition
until VDD > 6 V and VSS < −4 V and the initialization sequence has
finished. The outputs then go to their power-on default value.
TRANSFER FUNCTION
The output voltage of a DAC in the AD5362/AD5363 is dependent on the value in the input register, the value of the M and C
registers, and the value in the offset DAC.
AD5362 Transfer Function
The input code is the value in the X1A or X1B register that is
applied to the DAC (X1A, X1B default code = 32,768).
where:
DAC_CODE should be within the range of 0 to 16,383.
For 12 V span, VREF = 3.0 V.
For 20 V span, VREF = 5.0 V.
OFFSET_CODE is the code loaded to the offset DAC. On powerup, the default code loaded to the offset DAC is 8192 (0x2000).
With a 5 V reference, this gives a span of −10 V to +10 V.
REFERENCE SELECTION
The AD5362/AD5363 have two reference input pins. The
voltage applied to the reference pins determines the output
voltage span on VOUT0 to VOUT7. VREF0 determines the
voltage span for VOUT0 to VOUT3 (Group 0), and VREF1
determines the voltage span for VOUT4 to VOUT7 (Group 1).
The reference voltage applied to each VREF pin can be different, if required, allowing each group of four channels to have a
different voltage span. The output voltage range and span can
be adjusted further by programming the offset and gain
registers for each channel as well as programming the offset
DAC. If the offset and gain features are not used (that is, the M
and C registers are left at their default values), the required
reference levels can be calculated as follows:
VREF = (VOUTMAX − VOUTMIN)/4
where:
M = code in gain register − default code = 216 – 1.
C = code in offset register − default code = 215.
If the offset and gain features of the AD5362/AD5363 are used,
the required output range is slightly different. The selected
output range should take into account the system offset and
gain errors that need to be trimmed out. Therefore, the selected
output range should be larger than the actual, required range.
The DAC output voltage is calculated as follows:
The required reference levels can be calculated as follows:
DAC_CODE = INPUT_CODE × (M + 1)/216 + C − 215
VOUT = 4 × VREF × (DAC_CODE − (OFFSET_CODE ×
4))/216 + VSIGGND
where:
DAC_CODE should be within the range of 0 to 65,535.
For 12 V span, VREF = 3.0 V.
For 20 V span, VREF = 5.0 V.
OFFSET_CODE is the code loaded to the offset DAC. It is
multiplied by 4 in the transfer function because this DAC is a
14-bit device. On power-up, the default code loaded to the
1.
2.
3.
4.
5.
Rev. A | Page 18 of 28
Identify the nominal output range on VOUT.
Identify the maximum offset span and the maximum gain
required on the full output signal range.
Calculate the new maximum output range on VOUT,
including the expected maximum offset and gain errors.
Choose the new required VOUTMAX and VOUTMIN, keeping the VOUT limits centered on the nominal values. Note
that VDD and VSS must provide sufficient headroom.
Calculate the value of VREF as follows:
VREF = (VOUTMAX − VOUTMIN)/4
AD5362/AD5363
Reference Selection Example
Reducing Full-Scale Error
If
Full-scale error can be reduced as follows:
Nominal output range = 20 V (−10 V to +10 V)
1.
2.
3.
Offset error = ±100 mV
Gain error = ±3%, and
SIGGND = AGND = 0 V
4.
Then
Gain error = ±3%
=> Maximum positive gain error = 3%
=> Output range including gain error = 20 + 0.03(20) = 20.6 V
AD5362 Calibration Example
Offset error = ±100 mV
=> Maximum offset error span = 2(100 mV) = 0.2 V
=> Output range including gain error and offset error =
20.6 V + 0.2 V = 20.8 V
This example assumes that a −10 V to +10 V output is required.
The DAC output is set to −10 V but measured at −10.03 V. This
gives a zero-scale error of −30 mV.
1 LSB = 20 V/65,536 = 305.176 μV
VREF calculation
Actual output range = 20.6 V, that is, −10.3 V to +10.3 V
(centered);
VREF = (10.3 V + 10.3 V)/4 = 5.15 V
30 mV = 98 LSBs
If the solution yields an inconvenient reference level, the user
can adopt one of the following approaches:
•
•
•
Use a resistor divider to divide down a convenient, higher
reference level to the required level.
Select a convenient reference level above VREF and modify
the gain and offset registers to digitally downsize the reference.
In this way, the user can use almost any convenient reference
level but can reduce the performance by overcompaction of
the transfer function.
Use a combination of these two approaches.
CALIBRATION
The user can perform a system calibration on the AD5362/
AD5363 to reduce gain and offset errors to below 1 LSB. This
reduction is achieved by calculating new values for the M and
C registers and reprogramming them.
The M and C registers should not be programmed until both
the zero-scale and full-scale errors are calculated.
Reducing Zero-Scale Error
Zero-scale error can be reduced as follows:
1.
2.
3.
Measure the zero-scale error.
Set the output to the highest possible value.
Measure the actual output voltage and compare it to the
required value. Add this error to the zero-scale error. This
is the span error, which includes the full-scale error.
Calculate the number of LSBs equivalent to the span error
and subtract this number from the default value of the M
register. Note that only positive full-scale error can be
reduced.
Set the output to the lowest possible value.
Measure the actual output voltage and compare it to the
required value. This gives the zero-scale error.
Calculate the number of LSBs equivalent to the error and
add this number to the default value of the C register. Note
that only negative zero-scale error can be reduced.
The full-scale error can now be calculated. The output is set to
10 V and a value of 10.02 V is measured. This gives a full-scale
error of +20 mV and a span error of +20 mV – (–30 mV) =
+50 mV.
50 mV = 164 LSBs
The errors can now be removed as follows:
1.
2.
3.
Add 98 LSBs to the default C register value:
(32,768 + 98) = 32,866
Subtract 164 LSBs from the default M register value:
(65,535 − 164) = 65,371
Program the M register to 65,371; program the C register
to 32,866.
ADDITIONAL CALIBRATION
The techniques described in the previous section are usually
enough to reduce the zero-scale and full-scale errors in most
applications. However, there are limitations whereby the errors
may not be sufficiently reduced. For example, the offset (C)
register can only be used to reduce the offset caused by the
negative zero-scale error. A positive offset cannot be reduced.
Likewise, if the maximum voltage is below the ideal value, that
is, a negative full-scale error, the gain (M) register cannot be
used to increase the gain to compensate for the error.
These limitations can be overcome by increasing the reference
value. With a 2.5 V reference, a 10 V span is achieved. The ideal
voltage range, for the AD5362 or the AD5363, is −5 V to +5 V.
Using a +2.6 V reference increases the range to −5.2 V to +5.2 V.
Clearly, in this case, the offset and gain errors are insignificant,
and the M and C registers can be used to raise the negative
voltage to −5 V and then reduce the maximum voltage to +5 V
to give the most accurate values possible.
Rev. A | Page 19 of 28
AD5362/AD5363
RESET FUNCTION
The reset function is initiated by the RESET pin. On the rising
edge of RESET, the AD5362/AD5363 state machine initiates a
reset sequence to reset the X, M, and C registers to their default
values. This sequence typically takes 300 μs, and the user should
not write to the part during this time. On power-up, it is recommended that the user bring RESET high as soon as possible to
properly initialize the registers.
When the reset sequence is complete (and provided that CLR is
high), the DAC output is at a potential specified by the default
register settings, which is equivalent to SIGGNDx. The DAC
outputs remain at SIGGNDx until the X, M, or C register is
updated and LDAC is taken low. The AD5362/AD5363 can be
returned to the default state by pulsing RESET low for at least
30 ns. Note that, because the reset function is triggered by the
rising edge, bringing RESET low has no effect on the operation
of the AD5362/AD5363.
CLEAR FUNCTION
CLR is an active low input that should be high for normal
operation. The CLR pin has an internal 500 kΩ pull-down
resistor. When CLR is low, the input to each of the DAC output
buffer stages (VOUT0 to VOUT7) is switched to the externally
set potential on the relevant SIGGNDx pin. While CLR is low,
all LDAC pulses are ignored. When CLR is taken high again,
the DAC outputs return to their previous values. The contents
of the input registers and DAC Register 0 to DAC Register 7 are
not affected by taking CLR low. To prevent glitches appearing
on the outputs, CLR should be brought low whenever the
output span is adjusted by writing to the offset DAC.
BUSY AND LDAC FUNCTIONS
The value of an X2 (A or B) register is calculated each time the
user writes new data to the corresponding X1, C, or M registers.
During the calculation of X2, the BUSY output goes low. While
BUSY is low, the user can continue writing new data to the X1,
M, or C registers (see the Register Update Rates section for
more details), but no DAC output updates can take place.
The BUSY pin is bidirectional and has a 50 kΩ internal pull-up
resistor. When multiple AD5362 or AD5363 devices are used in
one system, the BUSY pins can be tied together. This is useful
when it is required that no DAC in any device be updated until
all other DACs are ready. When each device has finished updating the X2 (A or B) registers, it releases the BUSY pin. If
another device has not finished updating its X2 registers, it
holds BUSY low, thus delaying the effect of LDAC going low.
The DAC outputs are updated by taking the LDAC input low. If
LDAC goes low while BUSY is active, the LDAC event is stored
and the DAC outputs are updated immediately after BUSY goes
high. A user can also hold the LDAC input permanently low. In
this case, the DAC outputs update immediately after BUSY goes
high. Whenever the A/B select registers are written to, BUSY
also goes low, for approximately 600 ns.
The AD5362/AD5363 have flexible addressing that allows
writing of data to a single channel, all channels in a group, or
all channels in the device. This means that one, two, four, or
eight DAC register values may need to be calculated and
updated. Because there is only one multiplier shared between
eight channels, this task must be done sequentially, so the
length of the BUSY pulse varies according to the number of
channels being updated.
Table 9. BUSY Pulse Widths
Action
BUSY Pulse Width1
Loading input, C, or M to 1 channel2
Loading input, C, or M to 2 channels
Loading input, C, or M to 8 channels
1.5 μs maximum
2.1 μs maximum
5.7 μs maximum
1
2
BUSY pulse width = ((number of channels + 1) × 600 ns) + 300 ns.
A single channel update is typically 1 μs.
The AD5362/AD5363 contain an extra feature whereby a DAC
register is not updated unless its X2A or X2B register has been
written to since the last time LDAC was brought low. Normally,
when LDAC is brought low, the DAC registers are filled with
the contents of the X2A or X2B registers, depending on the
setting of the A/B select registers. However, the AD5362/
AD5363 update the DAC register only if the X2A or X2B data
has changed, thereby removing unnecessary digital crosstalk.
BIN/2SCOMP PIN
The BIN/2SCOMP pin determines if the output data is presented
as offset binary or twos complement. If this pin is low, the data
is straight binary. If it is high, the data is twos complement. This
affects only the X, C, and offset DAC registers; the M register and
the control and command data are interpreted as straight binary.
TEMPERATURE SENSOR
The on-chip temperature sensor provides a voltage output
at the TEMP_OUT pin that is linearly proportional to the
Centigrade temperature scale. The typical accuracy of the
temperature sensor is +1°C at +25°C and ±5°C over the −40°C
to +85°C range. Its nominal output voltage is 1.46 V at 25°C,
varying at 4.4 mV/°C. Its low output impedance, low selfheating, and linear output simplify interfacing to temperature
control circuitry and analog-to-digital converters.
Rev. A | Page 20 of 28
AD5362/AD5363
MONITOR FUNCTION
The AD5362/AD5363 contain a channel monitor function
that consists of an analog multiplexer addressed via the serial
interface, allowing any channel output to be routed to the
MON_OUT pin for monitoring using an external ADC. In
addition, two monitor inputs, MON_IN0 and MON_IN1,
are provided, which can also be routed to MON_OUT. The
monitor function is controlled by the monitor register, which
allows the monitor output to be enabled or disabled, and selects
a DAC channel or one of the monitor pins. When disabled, the
monitor output is high impedance so that several monitor
outputs can be connected in parallel with only one enabled at
a time. Table 10 shows the monitor register settings.
Table 10. Monitor Register Functions
F5
0
1
1
1
1
1
1
1
1
1
1
1
F4
X
X
0
0
0
0
0
0
0
0
1
1
F3
X
X
0
0
0
0
1
1
1
1
0
0
F2
X
X
0
0
0
0
0
0
0
0
0
0
F1
X
X
0
0
1
1
0
0
1
1
0
0
F0
X
X
0
1
0
1
0
1
0
1
0
1
Function
MON_OUT disabled
MON_OUT enabled
MON_OUT = VOUT0
MON_OUT = VOUT1
MON_OUT = VOUT2
MON_OUT = VOUT3
MON_OUT = VOUT4
MON_OUT = VOUT5
MON_OUT = VOUT6
MON_OUT = VOUT7
MON_OUT = MON_IN0
MON_OUT = MON_IN1
The multiplexer is implemented as a series of analog switches.
Because this could conceivably cause a large amount of current
to flow from the input of the multiplexer (VOUTx or MON_INx)
to the output of the multiplexer (MON_OUT), care should be
taken to ensure that whatever is connected to the MON_OUT
pin is of high enough impedance to prevent the continuous
current limit specification from being exceeded. Because the
MON_OUT pin is not buffered, the amount of current drawn
from this pin creates a voltage drop across the switches, which
in turn leads to an error in the voltage being monitored. Where
accuracy is important, it is recommended that the MON_OUT
pin be buffered. Figure 20 shows the typical error due to
MON_OUT current.
GPIO PIN
The AD5362/AD5363 have a general-purpose I/O pin, GPIO.
This pin can be configured as an input or an output and read
back or programmed (when configured as an output) via the
serial interface. Typical applications for this pin include monitoring the status of a logic signal, a limit switch, or controlling
an external multiplexer. The GPIO pin is configured by writing
to the GPIO register, which has the special function code of
001101 (see Table 15 and Table 16).
When Bit F1 is set, the GPIO pin becomes an output and Bit F0
determines whether the pin is high or low. The GPIO pin can be
set as an input by writing 0 to both Bit F1 and Bit F0. The status
of the GPIO pin can be determined by initiating a read operation
using the appropriate bits in Table 17. The status of the pin is
indicated by the LSB of the register read.
POWER-DOWN MODE
The AD5362/AD5363 can be powered down by setting Bit 0 in
the control register to 1. This turns off the DACs, thus reducing
the current consumption. The DAC outputs are connected to
their respective SIGGNDx potentials. The power-down mode
does not change the contents of the registers, and the DACs
return to their previous voltage when the power-down bit is
cleared to 0.
THERMAL SHUTDOWN FUNCTION
The AD5362/AD5363 can be programmed to shut down the
DACs if the temperature on the die exceeds 130°C. Setting Bit 1
in the control register to 1 enables this function (see Table 16).
If the die temperature exceeds 130°C, the AD5362/AD5363
enter a thermal shutdown mode, which is equivalent to setting
the power-down bit in the control register. To indicate that the
AD5362/AD5363 have entered thermal shutdown mode, Bit 4
of the control register is set to 1. The AD5362/AD5363 remain
in thermal shutdown mode, even if the die temperature falls,
until Bit 1 in the control register is cleared to 0.
TOGGLE MODE
The AD5362/AD5363 have two X2 registers per channel, X2A
and X2B, which can be used to switch the DAC output between
two levels with ease. This approach greatly reduces the overhead
required by a microprocessor, which would otherwise need to
write to each channel individually. When the user writes to the
X1A, X1B, M, or C register, the calculation engine takes a certain
amount of time to calculate the appropriate X2A or X2B value.
If an application, such as a data generator, requires that the DAC
output switch between two levels only, any method that reduces
the amount of calculation time necessary is advantageous. For
the data generator example, the user needs only to set the high
and low levels for each channel once by writing to the X1A and
X1B registers. The values of X2A and X2B are calculated and
stored in their respective registers. The calculation delay,
therefore, happens only during the setup phase, that is, when
programming the initial values. To toggle a DAC output between
the two levels, it is only required to write to the relevant A/B
select register to set the MUX2 register bit. Furthermore,
because there are four MUX2 control bits per register, it is
possible to update eight channels with just two writes. Table 18
shows the bits that correspond to each DAC output.
Rev. A | Page 21 of 28
AD5362/AD5363
SERIAL INTERFACE
The AD5362/AD5363 contain a high speed SPI operating at
clock frequencies up to 50 MHz (20 MHz for read operations).
To minimize both the power consumption of the device and
on-chip digital noise, the interface powers up fully only when
the device is being written to, that is, on the falling edge of
SYNC. The serial interface is 2.5 V LVTTL-compatible when
operating from a 2.5 V to 3.6 V DVCC supply. It is controlled by
four pins: SYNC (frame synchronization input), SDI (serial data
input pin), SCLK (clocks data in and out of the device), and
SDO (serial data output pin for data readback).
The input register addressed is updated on the rising edge of
SYNC. For another serial transfer to take place, SYNC must be
taken low again.
SPI READBACK MODE
The AD5362/AD5363 allow data readback via the serial
interface from every register directly accessible to the serial
interface, that is, all registers except the X2A, X2B, and DAC
data registers. To read back a register, it is first necessary to
tell the AD5362/AD5363 which register is to be read. This is
achieved by writing a word whose first two bits are the Special
Function Code 00 to the device. The remaining bits then
determine which register is to be read back.
SPI WRITE MODE
The AD5362/AD5363 allow writing of data via the serial interface to every register directly accessible to the serial interface,
that is, all registers except the X2A, X2B, and DAC registers.
The X2A and X2B registers are updated when writing to the
X1A, X1B, M, and C registers, and the DAC data registers are
updated by LDAC. The serial word (see Table 11 or Table 12)
is 24 bits long: 16 (AD5362) or 14 (AD5363) of these bits are
data bits; six bits are address bits; and two bits are mode bits
that determine what is done with the data. Two bits are reserved
on the AD5363.
If a readback command is written to a special function register,
data from the selected register is clocked out of the SDO pin
during the next SPI operation. The SDO pin is normally threestated but becomes driven as soon as a read command is issued.
The pin remains driven until the register data is clocked out.
See Figure 5 for the read timing diagram. Note that due to the
timing requirements of t22 (25 ns), the maximum speed of the
SPI interface during a read operation should not exceed 20 MHz.
REGISTER UPDATE RATES
The serial interface works with both a continuous and a burst
(gated) serial clock. Serial data applied to SDI is clocked into
the AD5362/AD5363 by clock pulses applied to SCLK. The first
falling edge of SYNC starts the write cycle. At least 24 falling
clock edges must be applied to SCLK to clock in 24 bits of data
before SYNC is taken high again. If SYNC is taken high before
the 24th falling clock edge, the write operation is aborted.
The value of the X2A register or the X2B register is calculated
each time the user writes new data to the corresponding X1, C,
or M register. The calculation is performed by a three-stage
process. The first two stages take approximately 600 ns each, and
the third stage takes approximately 300 ns. When the write to an
X1, C, or M register is complete, the calculation process begins.
If the write operation involves the update of a single DAC
channel, the user is free to write to another register, provided
that the write operation does not finish until the first-stage
calculation is complete, that is, 600 ns after the completion of
the first write operation. If a group of channels is being updated
by a single write operation, the first-stage calculation is repeated
for each channel, taking 600 ns per channel. In this case, the
user should not complete the next write operation until this time
has elapsed.
If a continuous clock is used, SYNC must be taken high before the
25th falling clock edge. This inhibits the clock within the AD5362/
AD5363. If more than 24 falling clock edges are applied before
SYNC is taken high again, the input data becomes corrupted.
If an externally gated clock of exactly 24 pulses is used, SYNC
can be taken high any time after the 24th falling clock edge.
Table 11. AD5362 Serial Word Bit Assignment
I23
M1
I22
M0
I21
A5
I20
A4
I19
A3
I18
A2
I17
A1
I16
A0
I15
D15
I14
D14
I13
D13
I12
D12
I11
D11
I10
D10
I14
D12
I13
D11
I12
D10
I11
D9
I10
D8
I9
D9
I8
D8
I7
D7
I6
D6
I5
D5
I4
D4
I3
D3
I2
D2
I1
D1
I0
D0
I8
D6
I7
D5
I6
D4
I5
D3
I4
D2
I3
D1
I2
D0
I1 1
0
I01
0
Table 12. AD5363 Serial Word Bit Assignment
I23
M1
1
I22
M0
I21
A5
I20
A4
I19
A3
I18
A2
I17
A1
I16
A0
I15
D13
I9
D7
Bit I1 and Bit I0 are reserved for future use and should be 0 when writing the serial word. These bits read back as 0.
Rev. A | Page 22 of 28
AD5362/AD5363
PACKET ERROR CHECKING
CHANNEL ADDRESSING AND SPECIAL MODES
To verify that data has been received correctly in noisy environments, the AD5362/AD5363 offer the option of error checking
based on an 8-bit (CRC-8) cyclic redundancy check. The device
controlling the AD5362/AD5363 should generate an 8-bit
checksum using the polynomial C(x) = x8 + x2 + x1 + 1. This is
added to the end of the data-word, and 32 data bits are sent to
the AD5362/AD5363 before taking SYNC high. If the AD5362/
AD5363 see a 32-bit data frame, an error check is performed
when SYNC goes high. If the checksum is valid, the data is
written to the selected register. If the checksum is invalid, the
packet error check (PEC) output goes low and Bit 3 of the
control register is set. After reading the control register, Bit 3
is cleared automatically and PEC goes high again.
If the mode bits are not 00, the data-word D15 to D0 (AD5362)
or D13 to D0 (AD5363) is written to the device. Address Bit A4
to Address Bit A0 determine which channels are written to, and
the mode bits determine to which register (X1A, X1B, C, or M)
the data is written, as shown in Table 13 and Table 14. Data is to
be written to the X1A register when the A/B bit in the control
register is 0, or to the X1B register when the A/B bit is 1.
M1
1
1
0
0
SCLK
SDI
Table 14 shows which groups and which channels are addressed
for every combination of Address Bit A4 to Address Bit A0.
Table 13. Mode Bits
UPDATE ON SYNC HIGH
SYNC
MSB
D23
The AD5362/AD5363 have very flexible addressing that allows
the writing of data to a single channel, all channels in a group,
or all channels in the device.
LSB
D0
24-BIT DATA
M0
1
0
1
0
Action
Write to DAC data (X) register
Write to DAC offset (C) register
Write to DAC gain (M) register
Special function, used in combination with other
bits of the data-word
24-BIT DATA TRANSFER—NO ERROR CHECKING
UPDATE AFTER SYNC HIGH
ONLY IF ERROR CHECK PASSED
SYNC
SCLK
LSB
D8
D7
24-BIT DATA
SDI
D0
8-BIT FCS
PEC GOES LOW IF
ERROR CHECK FAILS
PEC
24-BIT DATA TRANSFER WITH ERROR CHECKING
05762-026
MSB
D31
Figure 24. SPI Write With and Without Error Checking
Table 14. Group and Channel Addressing
Address Bit A2
to Address Bit A0
000
001
010
011
100
101
110
111
00
All groups, all channels
Group 0, all channels
Group 1, all channels
Unused
Unused
Unused
Unused
Unused
Address Bit A4 to Address Bit A3
01
10
Group 0, Channel 0
Group 1, Channel 0
Group 0, Channel 1
Group 1, Channel 1
Group 0, Channel 2
Group 1, Channel 2
Group 0, Channel 3
Group 1, Channel 3
Unused
Unused
Unused
Unused
Unused
Unused
Unused
Unused
Rev. A | Page 23 of 28
11
Unused
Unused
Unused
Unused
Unused
Unused
Unused
Unused
AD5362/AD5363
SPECIAL FUNCTION MODE
If the mode bits are 00, the special function mode is selected, as shown in Table 15. Bit I21 to Bit I16 of the serial data-word select the
special function, and the remaining bits are data required for execution of the special function, for example, the channel address for data
readback. The codes for the special functions are shown in Table 16. Table 17 shows the addresses for data readback.
Table 15. Special Function Mode
I23
0
I22
0
I21
S5
I20
S4
I19
S3
I18
S2
I17
S1
I16
S0
I15
F15
I14
F14
I13
F13
I12
F12
I11
F11
I10
F10
I9
F9
I8
F8
I7
F7
I6
F6
I5
F5
I4
F4
I3
F3
I2
F2
I1
F1
Table 16. Special Function Codes
S5
0
0
Special Function Code
S4 S3 S2 S1 S0
0
0
0
0
0
0
0
0
0
1
Data (F15 to F0)
0000 0000 0000 0000
XXXX XXXX XXXX X [F2:F0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
XX [F13:F0]
XX [F13:F0]
Reserved
See Table 17
XXXX XXXX XXXX [F3:F0]
XXXX XXXX XXXX [F3:F0]
Reserved
Reserved
Reserved
XXXX XXXX [F7:F0]
0
0
1
1
0
0
XXXX XXXX XX [F5:F0]
0
0
1
1
0
1
XXXX XXXX XXXX XX [F1:F0]
Action
NOP.
Write control register.
F4 = 1: Temperature over 130°C.
F4 = 0: Temperature below 130°C.
Read-only bit. This bit should be 0 when writing to the control register.
F3 = 1: PEC error.
F3 = 0: No PEC error. Reserved.
Read-only bit. This bit should be 0 when writing to the control register.
F2 = 1: Select Register X1B for input.
F2 = 0: Select Register X1A for input.
F1 = 1: Enable thermal shutdown mode.
F1 = 0: Disable thermal shutdown mode.
F0 = 1: Software power-down.
F0 = 0: Software power-up.
Write data in F13 to F0 to OFS0 register.
Write data in F13 to F0 to OFS1 register.
Select register for readback.
Write data in F3 to F0 to A/B Select Register 0.
Write data in F3 to F0 to A/B Select Register 1.
Block write to A/B select registers.
F7 to F0 = 0: Write all 0s (all channels use X2A register).
F7 to F0 = 1: Write all 1s (all channels use X2B register).
F5 = 1: Monitor enable.
F5 = 0: Monitor disable.
F4 = 1: Monitor input pin selected by F0.
F4 = 0: Monitor DAC channel selected by F3:F0 (see Table 10).
F3 = not used if F4 = 1.
F2 = not used if F4 = 1.
F1 = not used if F4 = 1.
F0 = 0: MON_IN0 selected for monitoring (if F4 and F5 = 1).
F0 = 1: MON_IN1 selected for monitoring (if F4 and F5 = 1).
GPIO configure and write.
F1 = 1: GPIO is an output. Data to output is written to F0.
F1 = 0: GPIO is an input. Data can be read from F0 on readback.
Rev. A | Page 24 of 28
I0
F0
AD5362/AD5363
Table 17. Address Codes for Data Readback1
F15
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
2
F14
0
0
1
1
0
0
0
0
0
0
0
0
0
0
F13
0
1
0
1
0
0
0
0
0
0
0
0
0
0
F12
F11
F10
F9
F8
F7
Bit F12 to Bit F7 select the channel to be read back;
Channel 0 = 001000 to Channel 3 = 001011
Channel 4 = 010000 to Channel 7 = 010011
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
1
1
1
0
0
0
0
0
1
1
0
1
1
0
0
1
1
1
0
1
0
0
1
0
1
0
1
Bits1
F3
DAC 3
DAC 7
F2
DAC 2
DAC 6
Register Read
X1A register
X1B register
C register
M register
Control register
OFS0 data register
OFS1 data register
Reserved
A/B Select Register 0
A/B Select Register 1
Reserved
Reserved
Reserved
GPIO read (data in F0)2
Bit F6 to Bit F0 are don’t cares for the data readback function.
Bit F6 to Bit F0 should be 0 for GPIO read.
Table 18. DACs Selected by A/B Select Registers
A/B Select
Register
0
1
1
F7
Reserved
Reserved
F6
Reserved
Reserved
F5
Reserved
Reserved
F4
Reserved
Reserved
If the bit is set to 0, Register X2A is selected. If the bit is set to 1, Register X2B is selected.
Rev. A | Page 25 of 28
F1
DAC 1
DAC 5
F0
DAC 0
DAC 4
AD5362/AD5363
APPLICATIONS INFORMATION
The AD5362/AD5363 should have ample supply decoupling of
10 μF in parallel with 0.1 μF on each supply located as close to
the package as possible, ideally right up against the device. The
10 μF capacitors are the tantalum bead type. The 0.1 μF capacitor
should have low effective series resistance (ESR) and low effective
series inductance (ESI)—typical of the common ceramic types
that provide a low impedance path to ground at high frequencies—
to handle transient currents due to internal logic switching.
Digital lines running under the device should be avoided because
they can couple noise onto the device. The analog ground plane
should be allowed to run under the AD5362/AD5363 to avoid
noise coupling. The power supply lines of the AD5362/AD5363
should use as large a trace as possible to provide low impedance
paths and reduce the effects of glitches on the power supply line.
Fast switching digital signals should be shielded with digital
ground to avoid radiating noise to other parts of the board, and
they should never be run near the reference inputs. It is essential
to minimize noise on the VREF0 and VREF1 lines.
Avoid crossover of digital and analog signals. Traces on opposite sides of the board should run at right angles to each other.
This reduces the effects of feedthrough through the board. A
microstrip technique is by far the best approach, but it is not
always possible with a double-sided board. In this technique,
the component side of the board is dedicated to ground plane,
while signal traces are placed on the solder side.
INTERFACING EXAMPLES
The SPI interface of the AD5362/AD5363 is designed to allow
the parts to be easily connected to industry-standard DSPs and
microcontrollers. Figure 25 shows how the AD5362/AD5363 can
connect to the Analog Devices, Inc., Blackfin® DSP. The Blackfin
has an integrated SPI port that can be connected directly to the
SPI pins of the AD5362 or AD5363, and programmable I/O
pins that can be used to set or read the state of the digital input
or output pins associated with the interface.
AD5362/
AD5363
SPISELx
SYNC
SCK
SCLK
ADSP-BF531
MOSI
SDI
MISO
SDO
PF10
RESET
PF9
LDAC
PF8
CLR
PF7
BUSY
05762-023
In any circuit where accuracy is important, careful consideration of the power supply and ground return layout helps to
ensure the rated performance. The printed circuit boards on
which the AD5362/AD5363 are mounted should be designed so
that the analog and digital sections are separated and confined
to certain areas of the board. If the AD5362/AD5363 are in a
system where multiple devices require an AGND-to-DGND
connection, the connection should be made at one point only.
The star ground point should be established as close as possible
to the device. For supplies with multiple pins (VSS, VDD, DVCC),
it is recommended that these pins be tied together and that each
supply be decoupled only once.
care should be taken to ensure that the ground pins are
connected to the supply grounds before the positive or negative
supplies are connected. This is required to prevent currents
from flowing in directions other than toward an analog or
digital ground.
Figure 25. Interfacing to a Blackfin DSP
The Analog Devices ADSP-21065L is a floating-point DSP with
two serial ports (SPORTs). Figure 26 shows how one SPORT can
be used to control the AD5362 or AD5363. In this example, the
transmit frame synchronization (TFSx) pin is connected to the
receive frame synchronization (RFSx) pin. Similarly, the transmit
and receive clocks (TCLKx and RCLKx) are also connected. The
user can write to the AD5362/AD5363 by writing to the transmit
register of the ADSP-21065L. A read operation can be accomplished by first writing to the AD5362/AD5363 to tell the part
that a read operation is required. A second write operation with
an NOP instruction causes the data to be read from the
AD5362/AD5363. The DSP receive interrupt can be used to
indicate when the read operation is complete.
As is the case for all thin packages, care must be taken to avoid
flexing the package and to avoid a point load on the surface of
this package during the assembly process.
POWER SUPPLY SEQUENCING
When the supplies are connected to the AD5362/AD5363, it
is important that the AGND and DGND pins be connected
to the relevant ground plane before the positive or negative
supplies are applied. In most applications, this is not an issue
because the ground pins for the power supplies are connected
to the ground pins of the AD5362/AD5363 via ground planes.
When the AD5362/AD5363 are to be used in a hot-swap card,
Rev. A | Page 26 of 28
ADSP-21065L
AD5362/
AD5363
TFSx
RFSx
SYNC
TCLKx
RCLKx
SCLK
DTxA
SDI
DRxA
SDO
FLAG0
RESET
FLAG1
LDAC
FLAG2
CLR
FLAG3
BUSY
Figure 26. Interfacing to an ADSP-21065L DSP
05762-024
POWER SUPPLY DECOUPLING
AD5362/AD5363
OUTLINE DIMENSIONS
0.75
0.60
0.45
12.20
12.00 SQ
11.80
1.60
MAX
52
40
39
1
PIN 1
10.20
10.00 SQ
9.80
TOP VIEW
(PINS DOWN)
1.45
1.40
1.35
0.15
0.05
0.20
0.09
7°
3.5°
0°
SEATING
PLANE
13
27
14
0.10
COPLANARITY
VIEW A
VIEW A
26
0.38
0.32
0.22
0.65
BSC
LEAD PITCH
051706-A
ROTATED 90° CCW
COMPLIANT TO JEDEC STANDARDS MS-026-BCC
Figure 27. 52-Lead Low Profile Quad Flat Package [LQFP]
(ST-52)
Dimensions shown in millimeters
8.00
BSC SQ
0.60 MAX
0.50
0.40
0.30
12° MAX
SEATING
PLANE
29
28
15 14
0.25 MIN
6.50
REF
0.80 MAX
0.65 TYP
0.50 BSC
6.25
6.10 SQ
5.95
EXPOSED
PAD
(BOTTOM VIEW)
7.75
BSC SQ
0.05 MAX
0.02 NOM
COPLANARITY
0.08
0.20 REF
COMPLIANT TO JEDEC STANDARDS MO-220-VLLD-2
Figure 28. 56-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
8 mm × 8 mm Body, Very Thin Quad
(CP-56-1)
Dimensions shown in millimeters
Rev. A | Page 27 of 28
112805-0
TOP
VIEW
PIN 1
INDICATOR
56 1
43
42
PIN 1
INDICATOR
1.00
0.85
0.80
0.30
0.23
0.18
0.60 MAX
AD5362/AD5363
ORDERING GUIDE
Model
AD5362BSTZ 1
AD5362BSTZ-REEL1
AD5362BCPZ1
AD5362BCPZ-REEL71
EVAL-AD5362EBZ1
AD5363BSTZ1
AD5363BSTZ-REEL1
AD5363BCPZ1
AD5363BCPZ-REEL71
EVAL-AD5363EBZ1
1
Temperature Range
−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
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
Package Description
52-Lead Low Profile Quad Flat Package [LQFP]
52-Lead Low Profile Quad Flat Package [LQFP]
56-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
56-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
Evaluation Board
52-Lead Low Profile Quad Flat Package [LQFP]
52-Lead Low Profile Quad Flat Package [LQFP]
56-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
56-Lead Lead Frame Chip Scale Package [LFCSP_VQ]
Evaluation Board
Z = RoHS Compliant Part.
©2008 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05762-0-3/08(A)
Rev. A | Page 28 of 28
Package Option
ST-52
ST-52
CP-56-1
CP-56-1
ST-52
ST-52
CP-56-1
CP-56-1
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