Philips Semiconductors Linear Products
8-bit multiplying D/A converter
Product specification
MC1508-8/1408-8
VCC
0.1µF
eIN
13
5
6
14
7
15
8 MC1508 1
9 MC1408 2
10
4
11
16
+2VDC
1.0k
R14
0.1µF
1.0k
RL
FOR SETTLING TIME
MEASUREMENT
eO
(ALL BITS
SWITCHED LOW
2.4V
eIN
0.4V
1.0V
SETTLING TIME
0
tPHL = tPLH = 10ns
1.4V
USE RL to GND
FOR TURN OFF
MEASUREMENT
RL = 500Ω
12
TO HIGH)
tS = 70ns TYPICAL
51
3
0.1µF
15pF
CO ≤ 25pF
TRANSIENT 0
TO ±1/2LSB
RESPONSE
RL = 50Ω
VEE
–100
mV
tPLH
PIN 4 TO GND
tPHL
Figure 4. Transient Response and Settling Time
DIGITAL
INPUTS
A1 5
A2
A3
A4
A5
6
7
8
9
A6
10
11
A7
A8
12
(+) II
VI
VCC
ICC
TYPICAL VALUES R14 = R15 = 1k
VREF = +2.0V
C = 15pF
13
I14
14
R14
I15
15
VREF(+)
MC1508 1
R15
MC1408 2
4
16
IO
VO
OUTPUT
RL
3
IEE VEE
(SEE TEXT FOR VALUES OF C.)
VI AND II APPLY TO INPUTS A1 THROUGH A8
THE RESISTOR TIED TO PIN 15 IS TO TEMPERATURE COMPENSATE THE
BIAS CURRENT AND MAY NOT BE NECESSARY FOR ALL APPLICATIONS
IO + K
A1
A2
A3
A4
A5
A6
A7
A8
2 ) 4 ) 8 ) 16 ) 32 ) 64 ) 128 ) 256
VREF
where K + R14
and AN = “1” IF AN IS AT HIGH LEVEL
AN = “0” IF AN IS AT LOW LEVEL
Figure 5. Notation Definitions
VCC
13
5
6
14 1k
7
15
8
9
MC1508
MC1408
1
2
10
11
4
12
16
3 15pF
VEE
VREF
1k
RL = 50
SCOPE
dI
I dV
dt + RL dt
10%
90%
SLEWING TIME
Figure 6. Reference Current Slew Rate Measurement
0
2.0mA
August 31, 1994
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