LTC1450 Linear Technology, LTC1450 Datasheet - Page 12

• Manufacturer Part Number: LTC1450
• Description: Parallel Input/ 12-Bit Rail-to-Rail Micropower DACs in SSOP
• Manufacturer: Linear Technology

LTC1450/LTC1450L
TYPICAL APPLICATIONS
12
DECODE LOGIC
FROM P AND
DECODE LOGIC
SYSTEM RESET
FROM P AND
SYSTEM RESET
DATA BUS
FROM
FROM P
DATA BUS
FROM
FROM P
D
IN
D
IN
V
CC
DATA (0:11)
CSLSB
CSMSB
WR
LDAC
CLR
5V
DATA (0:11)
CSLSB
CSMSB
WR
LDAC
CLR
0.1 F
0.1 F
V
U
CC
LTC1450
V
Digitally Programmable Bilateral Current Source/Sink
CC
LTC1450
REFOUT
GND
REFOUT
N
GND
V
REF
V
REF
REFLO
REFHI
REFLO*
REFHI*
X1/X2
Bipolar Output 12-Bit DAC
X1/X2
V
OUT
V
OUT
R6
20k
10k
V
DAC
V
DAC
I
R1 = R3
R2 = R4 + R5
Z
20k
R1
OUT
OUT
10k
V
20k
*REFLO IS TIED TO REFOUT AND
TYING REFLO TO REFOUT AND REFHI TO GND IN THIS
APPLICATION OVERCOMES THE NEED FOR A PULL-DOWN
RESISTOR ON THE REFOUT PIN. REFOUT SEES A CONSTANT
LOAD TO GND INDEPENDENT OF V
R3
REFHI IS TIED TO GND
OUT
10k
=
=
(R2)(R3) – R1(R4 + R5)
4096
= 2.048 +
D
(R1)(R5)(R3 + R4)
IN
2
3
• 4.096 – V
–
+
3
2
10k
LT1097
+
–
D
–15V
LT
15V
IN
4096
®
– 4096
7
4
1097
– 5V
5V
REF
22.6k
21.5k
7
4
R2
R4
(R1)(R5)
4.096
6
R2
6
R5
1.13k
OUT
V
– 2.048V TO 2.047V
(1mV/LSB)
I
– 2.048mA TO 2.047mA
(1 A/LSB)
OUT
OUT
– 2.048V
V
2.047V
OUT
– 2.048mA
2.047mA
I
OUT
2048
LTC1450/50L • TA06
LTC1450/50L • TA05
2048
4095
4095
D
IN
D
IN