1
LTC7545A
Improved Industry Standard
Parallel 12-Bit Multiplying DAC
S
FEATURE
D
U
ESCRIPTIO
The LTC
®
7545A is a 12-bit multiplying digital-to-analog
converter (DAC) with a microprocessor compatible paral-
lel input. It is a superior pin compatible replacement for the
industry standard AD7545A and AD7545. Improvements
include better accuracy, better stability over temperature
and supply variations and lower sensitivity to output
amplifier offset.
This very versatile DAC is useful for 2-quadrant and
4-quadrant multiplying, programmable gain and filtering
and single supply noninverting voltage output operation.
Parts are available in 20-pin PDIP and SO packages and
commercial and industrial temperature grades.
■
Improved Direct Replacement for AD7545A
and AD7545
■
DNL and INL Over Temperature: ±0.5LSB
■
Gain Error: ±1LSB Maximum
■
4-Quadrant Multiplication
■
Single 5V or 15V Supply
■
Low Power Consumption
■
Low Cost
■
Process Control and Industrial Automation
■
Software Controlled Gain Adjustment
■
Digitally Controlled Filter and Power Supplies
■
Automatic Test Equipment
U
S
A
O
PPLICATI
, LTC and LT are registered trademarks of Linear Technology Corporation.
U
A
O
PPLICATITYPICAL
2-Quadrant Multiplying DAC Has Less Than
0.5LSB (Typ) Total Unadjusted Error
V
DD
V
REF
LTC7545A
R
FB
DGND
34–15
17
16 2
18
5V
V
IN
WR
CS
19 20
1
OUT1
33pF
V
OUT
7545A TA01
AGND
–
+
0.1µF
LT
®
1097
DIGITAL INPUT CODE
0
INTEGRAL NONLINEARITY (LSB)
4095
7545A TA02
1024 2048 3072
1.0
0.5
0
–0.5
–1.0 512 1536 2560 3584
T
A
= 85°CT
A
= 25°C
T
A
= –40°C
Integral Nonlinearity Over Temperature
2
LTC7545A
WU
U
PACKAGE/ORDER I FOR ATIO
A
U
G
W
A
W
U
W
ARBSOLUTEXI T
IS
V
DD
to AGND ............................................ –0.5V to 17V
V
DD
to DGND .............................................–0.5V to 17V
AGND to DGND.............................. –0.5V to V
DD
+ 0.5V
DGND to AGND.............................. –0.5V to V
DD
+ 0.5V
V
REF
to AGND,DGND ............................................. ±25V
R
FB
to AGND,DGND ............................................. . ±25V
Digital Inputs to DGND ................. –0.5V to V
DD
+ 0.5V
V
OUT1
to AGND, DGND ................. –0.5V to V
DD
+ 0.5V
Maximum Junction Temperature ..........................150°C
Operating Temperature Range
Commercial (K, L Versions) .................... 0°C to 70°C
Industrial (B, C Versions)................... –40° C to 85°C
Storage Temperature Range ................ –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
LTC7545ABG
LTC7545ABN
LTC7545ABSW
LTC7545ACG
LTC7545ACN
LTC7545ACSW
LTC7545AKG
LTC7545AKN
LTC7545AKSW
LTC7545ALG
LTC7545ALN
LTC7545ALSW
ORDER PART
NUMBER
T
JMAX
= XXX°C, θ
JA
= XXX°C/W (G)
T
JMAX
= 150°C, θ
JA
= 100°C/W (N)
T
JMAX
= 150°C, θ
JA
= 130°C/W (SW)
Consult factory for Military grade parts.
VDD = 5V or 15V, VREF = 10V, VOUT1 = AGND = 0V, TA = TMIN to TMAX, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
LTC7545AK/AB LTC7545AL/AC
SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
Accuracy
Resolution ●12 12 Bits
INL Integral Nonlinearity (Note 1) T
A
= 25°C±0.5 ±0.5 LSB
(Relative Accuracy) T
MIN
to T
MAX
●±0.5 ±0.5 LSB
DNL Differential Nonlinearity Guaranteed Monotonic T
A
= 25°C±1±0.5 LSB
T
MIN
to T
MAX
T
MIN
to T
MAX
●±1±0.5 LSB
GE Gain Error (Note 2) T
A
= 25°C±2±1LSB
T
MIN
to T
MAX
●±3±2LSB
Gain Temperature Coefficient (Note 3) ∆Gain/∆Temperature ●1 5 1 5 ppm/°C
I
LKG
OUT1 Leakage Current (Note 4) T
A
= 25°C±10 ±10 nA
T
MIN
to T
MAX
●±50 ±50 nA
PSRR Power Supply Rejection ●±0.002 ±0.002 %/%
Reference Input
R
REF
V
REF
Input Resistance (Note 5) ●8 11 15 8 11 15 kΩ
AC Performance
Output Current Settling Time (Notes 3, 6, 7) ●11µs
Propagation Delay (Notes 3, 6, 8) ●150 150 ns
Digital-to-Analog Glitch Impulse (Notes 6, 9) ●5 5 nV-sec
Multiplying Feedthrough Error V
REF
= ±10V, 10kHz Sine Wave ●55mV
P-P
Analog Outputs
C
OUT
Output Capacitance (Note 3) DB0 to DB11 = 0V, C
OUT1
●30 70 30 70 pF
WR, CS = 0V
DB0 to DB11 = V
DD,
C
OUT1
●60 150 60 150 pF
WR, CS = 0V
OUT1
AGND
DGND
DB11 (MSB)
DB10
DB9
DB8
DB7
DB6
DB5
RFB
VREF
VDD
WR
CS
DB0 (LSB)
DB1
DB2
DB3
DB4
1
2
3
4
5
6
7
8
9
10
TOP VIEW
20
19
18
17
16
15
14
13
12
11
N PACKAGE
20-LEAD PDIP
SW PACKAGE
20-LEAD PLASTIC SO WIDE
G PACKAGE
20-LEAD PLASTIC SSOP
3
LTC7545A
ELECTRICAL CHARACTERISTICS
VDD = 5V, VREF = 10V, VOUT1 = AGND = 0V, TA = TMIN to TMAX, unless otherwise noted.
ALL GRADES
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Digital Inputs
V
IH
Digital Input High Voltage ●2.4 V
V
IL
Digital Input Low Voltage ●0.8 V
I
IN
Digital Input Current ●0.001 ±1µA
C
IN
Digital Input Capacitance (Note 3) V
IN
= 0V ●8pF
Timing Characteristics (Note 3)
t
CS
CS to WR Setup Time ●100 ns
t
CH
CS to WR Hold Time ●0ns
t
WR
Write Pulse Width ●100 ns
t
DS
Data Setup Time ●100 ns
t
DH
Data Hold Time ●5ns
Power Supply
V
DD
Supply Voltage ●4.75 5 5.25 V
I
DD
Supply Current All Digital Inputs = V
IH
or V
IL
●2mA
All Digital Inputs = 0V or V
DD
●10 100 µA
VDD = 15V, VREF = 10V, VOUT1 = AGND = 0V, TA = TMIN to TMAX, unless otherwise noted.
The ● denotes specificatons which apply over the full operating
temperature range.
Note 1: ±0.5LSB = ±0.012% of full scale.
Note 2: Using internal feedback resistor.
Note 3: Guaranteed by design, not subject to test.
Note 4: I
OUT1
with DAC register loaded to all 0s.
Note 5: Typical temperature coefficient is 100ppm/°C.
Note 6: OUT1 load = 100Ω in parallel with 13pF.
Note 7: To 0.01% for a full-scale change, measured from the falling
edge of WR, CS = 0V.
Note 8: From digital input change to 90% of final analog output.
Note 9: V
REF
= 0V. DAC register contents changed from all 0s to all 1s
or all 1s to all 0s.
ALL GRADES
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Digital Inputs
V
IH
Digital Input High Voltage ●13.5 V
V
IL
Digital Input Low Voltage ●1.5 V
I
IN
Digital Input Current ●±1µA
C
IN
Digital Input Capacitance (Note 3) V
IN
= 0V ●8pF
Timing Characteristics (Note 3)
t
CS
CS to WR Setup Time ●75 ns
t
CH
CS to WR Hold Time ●0ns
t
WR
Write Pulse Width ●75 ns
t
DS
Data Setup Time ●60 ns
t
DH
Data Hold Time ●5ns
Power Supply
V
DD
Supply Voltage ●14.25 15 15.75 V
I
DD
Supply Current All Digital Inputs = V
IH
or V
IL
●2mA
All Digital Inputs = 0V or V
DD
●10 100 µA
4
LTC7545A
40k 10k
40k
20k
40k
20k
40k
20k
40k40k40k
DECODER
LOAD
V
DD
V
REF
R
FB
OUT1
AGND
DGND3
2
1
20
7545A BD
INPUT DATA LATCHES
16
45 67 15
DB11
(MSB) DB10 DB9 DB8
• • • • • • •
DB0
(LSB)
17
18
19
WR
CS
BLOCK DIAGRAM
W
TI I G DIAGRA
UWW
t
CH
t
CS
t
DS
t
DH
t
WR
DATA VALID
DATA IN
DB0 to DB11
WR
CS
7545A TD
5
LTC7545A
TYPICAL APPLICATIONS N
U
Unipolar Operation (2-Quadrant Multiplication)
ANALOG OUTPUT
VOUT
MSB LSB
1111 1111 1111 –VREF (4095/4096)
1000 0000 0000 –VREF (2048/4096) = –VREF/2
0000 0000 0001 –VREF (1/4096)
0000 0000 0000 0V
DIGITAL INPUT
BINARY NUMBER
IN DAC LATCH
Table 1. Unipolar Binary Code Table
V
DD
V
REF
LTC7545A
R
FB
OUT1
DGND
AGND
3
2
17
16
4–15
18
5V OR 15V
V
REF
–10V TO 10V
µP
WR
CS
DB11 to DB0
19 20
1
33pF
0.1µF
V
OUT
0V TO – V
REF
7545A TA03
–
+
LT1097
6
LTC7545A
TYPICAL APPLICATIONS N
U
Bipolar Operation (4-Quadrant Multiplication)
V
DD
V
REF
LTC7545A
R
FB
OUT1
DGND
AGND
3
2
17
16
4–15
18
5V OR 15V
V
REF
–10V TO 10V
µP
WR
CS
DB11–DB0
19 20
1
33pF
R1
10K
0.1µF
V
OUT
7545A TA04
–
+
1/2LT1112
–
+
1/2LT1112
R2
20K R3
20K
ANALOG OUTPUT
VOUT
Table 2. Bipolar Offset Binary Code Table
MSB LSB
1111 1111 1111 VREF (2047/2048)
1000 0000 0001 VREF (1/2048)
1000 0000 0000 0V
0111 1111 1111 –VREF (1/2048)
0000 0000 0000 –VREF (2048/2048) = –VREF
DIGITAL INPUT
BINARY NUMBER
IN DAC LATCH
7
LTC7545A
PACKAGE DESCRIPTION
U
Dimensions in inches (millimeters) unless otherwise noted.
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
N Package
20-Lead PDIP (Narrow 0.300)
(LTC DWG # 05-08-1510)
G Package
20-Lead Plastic SSOP (0.209)
(LTC DWG # 05-08-1640)
G20 SSOP 1098
0.13 – 0.22
(0.005 – 0.009)
0° – 8°
0.55 – 0.95
(0.022 – 0.037)
5.20 – 5.38**
(0.205 – 0.212)
7.65 – 7.90
(0.301 – 0.311)
12345678910
7.07 – 7.33*
(0.278 – 0.289)
1718 14 13 12 1115161920
1.73 – 1.99
(0.068 – 0.078)
0.05 – 0.21
(0.002 – 0.008)
0.65
(0.0256)
BSC 0.25 – 0.38
(0.010 – 0.015)
NOTE: DIMENSIONS ARE IN MILLIMETERS
DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.152mm (0.006") PER SIDE
DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.254mm (0.010") PER SIDE
*
**
N20 1098
0.020
(0.508)
MIN
0.125
(3.175)
MIN
0.130 ± 0.005
(3.302 ± 0.127)
0.065
(1.651)
TYP
0.045 – 0.065
(1.143 – 1.651)
0.018 ± 0.003
(0.457 ± 0.076)
0.005
(0.127)
MIN
0.100
(2.54)
BSC
0.255 ± 0.015*
(6.477 ± 0.381)
1.040*
(26.416)
MAX
12345678910
19 1112
131416 1517
18
20
0.009 – 0.015
(0.229 – 0.381)
0.300 – 0.325
(7.620 – 8.255)
0.325 +0.035
–0.015
+0.889
–0.381
8.255
()
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)
8
LTC7545A
sn7545a 7545afs LT/GP 0596 10K • PRINTED IN USA
LINEAR TECHNOLOGY C ORPORATION 1996
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX
: (408) 434-0507
●
TELEX
: 499-3977
PACKAGE DESCRIPTION
U
Dimensions in inches (millimeters) unless otherwise noted.
RELATED PARTS
PART NUMBER DESCRIPTON COMMENTS
LTC1257 Complete Serial I/O V
OUT
12-Bit DAC 5V to 15V Single Supply in 8-Pin SO and PDIP
LTC1450/LTC1450L Complete Parallel Input V
OUT
12-Bit DACs Rail-to-Rail V
OUT
, 3V/5V Single Supply, 12-Bit or (8 + 4) Bit Loading
LTC1451/LTC1452/LTC1453 Complete Serial I/O V
OUT
12-Bit DACs Rail-to-Rail V
OUT
, 3V/5V Single Supply in 8-Pin SO and PDIP
LTC7541A Parallel I/O Multiplying I
OUT
12-Bit DAC 12-Bit Wide Parallel Input
LTC7543/LTC8143 Serial I/O Multiplying I
OUT
12-Bit DACs Clear Pin and Serial Data Output (LTC8143)
LTC8043 Serial I/O Multiplying I
OUT
12-Bit DAC 8-Pin SO and PDIP
SW Package
20-Lead Plastic Small Outline (Wide 0.300)
(LTC DWG # 05-08-1620)
S20 (WIDE) 1098
NOTE 1
0.496 – 0.512*
(12.598 – 13.005)
20 19 18 17 16 15 14 13
12345678
0.394 – 0.419
(10.007 – 10.643)
910
1112
0.037 – 0.045
(0.940 – 1.143)
0.004 – 0.012
(0.102 – 0.305)
0.093 – 0.104
(2.362 – 2.642)
0.050
(1.270)
BSC 0.014 – 0.019
(0.356 – 0.482)
TYP
0° – 8° TYP
NOTE 1
0.009 – 0.013
(0.229 – 0.330) 0.016 – 0.050
(0.406 – 1.270)
0.291 – 0.299**
(7.391 – 7.595)
× 45°
0.010 – 0.029
(0.254 – 0.737)
NOTE:
1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS.
THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS
DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
*
**
