LT1016IS8 Linear Technology, LT1016IS8 Datasheet - Page 13

• Manufacturer Part Number: LT1016IS8
• Description: IC COMPARATOR 10NS HI-SPD 8-SOIC
• Manufacturer: Linear Technology
• Series: UltraFast™r
• Type: General Purposer

Specifications of LT1016IS8

• Number Of Elements: 1
• Output Type: CMOS, Complementary, TTL
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIO S I FOR ATIO
1.8ms, 12-Bit A/D Converter
The LT1016’s high speed is used to implement a very fast
12-bit A/D converter in Figure 15. The circuit is a modified
form of the standard successive approximation approach
and is faster than most commercial SAR 12-bit units. In
this arrangement the 2504 successive approximation reg-
ister (SAR), A1 and C1 test each bit, beginning with the
MSB, and produce a digital word representing V
Q1 TO Q5 RCA CA3127 ARRAY
*1% FILM RESISTOR
**PRECISION 0.01%; VISHAY S-102
3
74121
5V
4
IN B
9
1000pF
SD210
1N4148
HP5082-2810
5
Q
7
– 5V
6
1k
PARALLEL
U
–15V
OUTPUT
DIGITAL
5V
DATA
0.01µF
5V
U
LT1021
10V
MSB
16
24
13
CLK
V
COMP
+
– 5V
10V
5V
V
R
1k
1k
14
+
10k**
0.1µF
0.1µF
W
V
GND
R
15
–
10k
10Ω
10Ω
12
GND
Figure 15. 12-Bit 1.8ms SAR A-to-D
Q6
13
AM6012
E
–
+
+
–
U
– 5V
– 5V
AM2504
1
5V
5V
IN
LT1016
LT1016
’s value.
C3
C2
I
O
19
S
14
NC
15V
NC
V
CC
+
20
3
1/4 74S08
To get faster conversion time, the clock is controlled by the
window comparator monitoring the DAC input summing
junction. Additionally, the DMOS FET clamps the DAC
output to ground at the beginning of each clock cycle,
shortening DAC settling time. After the fifth bit is con-
verted, the clock runs at maximum speed.
–15V
V
–
17
D
11
1/2 74S74
LSB
I
RST
O
PRS
18
150k
1/4 74S00
0V TO 10V
CLOCK
V
IN
1/6 74S04
5V
0.01µF
Q4
Q5
2.5k**
1k
150Ω
150k
15k
1k
D
CLK
1/2 74S74
7.4MHz
PRS
620Ω*
1/6 74S04
Q
Q3
Q1 Q2
–15V
5V
27k
1/4 74S08
2.5k
620Ω*
1/4 74S00
–
+
LT1016
5V
LT1016
C1
– 5V
13
CONVERT
COMMAND
STATUS
NC
1016 F15