LTC1045
Programmable
Micropower Hex Translator/
Receiver/Driver
FEATURES
s
s
s
s
s
s
s
s
DESCRIPTIO
Efficiently Translate Voltage Levels
Internal Hysteresis for Noise Immunity
Output Latches Included
Three-State Outputs
Programmable Power/Speed
Power Can Be Completely Shut Off
±50V
on Inputs with External 100k Limit Resistor
1.2µs Response at 100µA Supply Current
The LTC
®
1045 is a hex level translator manufactured using
Linear Technology’s enhanced LTCMOS
TM
silicon gate
process. It consists of six high speed comparators with
output latches and three-state capability. Each compara-
tor’s plus input is brought out separately. The minus inputs
of comparators 1 to 4 are tied to V
TRIP1
while 5 and 6 are
tied to V
TRIP2
.
The I
SET
pin has several functions. When taken to V
+
the
outputs are latched and power is completely shut off.
Power/speed can be programmed by connecting I
SET
to V
–
through an external resistor.
APPLICATIO S
s
s
s
s
s
TTL/CMOS to
±5V
Analog Switch Drive
TTL to CMOS (3V to 15V V
CC
)
ECL to CMOS (3V to 15V V
CC
)
Ground Isolation Buffer
Low Power RS232 Line Receiver
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTCMOS is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
5V
20
TTL IN
XMT IN
Flat Ribbon Cable Driver/Receiver
5V
+
–
V
+
1
V
OH
V
OL
DIS
13
11
20
XMT OUT
66-FT FLAT RIBBON CABLE
Z
O
= 150Ω
ADJACENT CONDUCTORS
150Ω
RCV IN
V
+
1
V
OH
V
OL
DIS
13
11
RCV OUT
1.4V
I
SET
12
10
V
–
0.5V
XMT IN (5V/DIV)
XMT OUT (1V/DIV)
RCV IN (1V/DIV)
RCV OUT (5V/DIV)
100ns/DIV
045 TA01a
U
+
–
TTL OUT
I
SET
12
1045 TA01
U
U
V
–
10
1045fc
1
LTC1045
ABSOLUTE
MAXIMUM
RATINGS
(Notes 1, 2)
PACKAGE/ORDER INFORMATION
TOP VIEW
V
OH
IN1
IN2
IN3
IN4
IN5
IN6
V
TRIP2
V
TRIP1
1
2
3
4
5
6
7
8
9
20 V
+
19 OUT1
18 OUT2
17 OUT3
16 OUT4
15 OUT5
14 OUT6
13 DISABLE
12 I
SET
11 V
OL
.............. 18V
Output High Voltage (V
OH
) ......................................
≤
V
+
Input Voltage ....................................18V to (V
–
– 0.3V)
Output Short-Circuit Duration
(V
OH
– V
OL
≤
10V) ................................... Continuous
ESD (MIL-STD-883, Method 3015) .................... 2000V
Operating Temperature Range ................. –40°C to 85°C
Storage Temperature Range ................. – 55°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
OH
Total Supply Voltage (V
+
, V
to V
–
, V
OL
)
ORDER PART
NUMBER
LTC1045CN
LTC1045CSW
V
–
10
N PACKAGE
SW PACKAGE
20-LEAD PDIP 20-LEAD SO WIDE
T
JMAX
= 110°C,
θ
JA
= 90°C/ W (N)
T
JMAX
= 110°C,
θ
JA
= 90°C/ W (SW)
J PACKAGE
20-LEAD CERDIP
T
JMAX
= 150°C,
θ
JA
= 70°C/ W (J)
LTC1045CJ
OBSOLETE PACKAGE
Consider N Package for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
I
B
Input Bias Current
Trip Voltage Range (Pins 8, 9)
V
+
to V
–
Supply Current
V
+
to V
–
Supply Current in Shutdown
The
q
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
+
= V
OH
= 5V, V
–
= V
OL
= 0Vunless otherwise specified. (Note 3) .
CONDITIONS
V
–
≤
V
IN
≤
V
+
q
q
MIN
TYP
±1
MAX
0.5
V
+
– 2
3.5
4.5
1
V
–
2.5
I
S
I
OFF
V
REF
V
OH
V
OL
I
SINK
I
SOURCE
I
OZ
R
OH
R
OL
DISABLE = V
+
, R
SET
DISABLE = I
SET
=
R
SET
= 10k
V
+
= 10k
q
10
q
Voltage on I
SET
(Pin 12)
TTL Output High Voltage
TTL Output Low Voltage
Output Short-Circuit Sink Current
Output Short-Circuit Source Current
Three-State Leakage Current
Output Resistance to V
OH
Output Resistance to V
OL
I
SET
Voltage for Shutdown
DISABLE Input Logic Levels
0.9
q
q
q
q
I
OUT
I
OUT
= 1.6mA, V
+
= 4.5V
V
IN
= V
TRIP
– 100mV, V
OUT
= V
+
V
IN
= V
TRIP
+ 100mV, V
OUT
= V
–
= – 360µA, V
+
= 4.5V
0.6
2.4
7.5
5.5
4.0
3.2
1.25
4.4
0.2
15
8.0
0.005
0.4
q
DISABLE = V
+
, V
OL
≤
V
OUT
≤
V
OH
q
I
OUT
≤
100µA
q
260
100
q
q
I
OUT
≤
100µA
V
+
– 0.5
2.0
4.5
3
1
475
600
180
250
UNITS
nA
µA
V
mA
mA
nA
µA
V
V
V
V
mA
mA
mA
mA
µA
µA
Ω
Ω
Ω
Ω
V
V
V
V
V
1045fc
V
IH
V
IL
Input Supply Differential
(V
+
– V
–
) (Note 3)
Output Supply Differential
(V
OH
– V
OL
) (Note 3)
V
+
= 4.5V, V
–
= 0V
V
+
= 5.5V, V
–
= 0V
q
q
q
q
0.8
15
15
2
U
W
U
U
W W
W
LTC1045
AC ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER
t
d
t
SETUP
t
HOLD
t
ACC
t
IH
, t
OH
Response Time
Time Before Rising Edge of I
SET
that
Data Must Be Present
Time After Rising Edge of I
SET
that
Data Must Be Present
Falling Edge of DISABLE to Logic
Level (from Hi-Z State)
Rising Edge of DISABLE to Hi-Z State
CONDITIONS
The
q
denotes the specifications which apply over the full operating
+
= V = 5V, V
–
= V = 0V, unless otherwise specified.
temperature range, otherwise specifications are at T
A
= 25°C. V
OH
OL
MIN
q
TYP
MAX
250
350
UNITS
ns
ns
ns
ns
ns
ns
Test Circuit Figure 1
R
SET
= 10k,
±100mV
Drive
Test Circuit Figure 2
Test Circuit Figure 2
Test Circuit Figure 3
Test Circuit Figure 3
80
0
165
200
Note 1:
Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2:
The maximum differential voltage between any two power pins
(V
+
, V
–
, V
OH
and V
OL
) must not exceed 18V. The maximum recommended
operating differential is 15V.
Note 3:
During operation near the maximum supply voltage limit, care
should be taken to avoid or suppress power supply turn-on and turn-off
transients, power supply ripple or ground noise; any of these conditions
must not cause a supply differential to exceed the absolute maximum
rating.
TYPICAL PERFORMANCE CHARACTERISTICS
I
+
vs Temperature
5
V
+
= 5V
4
V
+
TO V
–
CURRENT (mA)
V
+
TO V
–
CURRENT (mA)
DELAY TIME (µs)
3
R
SET
= 0
2
R
SET
= 10k
1
R
SET
= 1M
0
–50
–25
75
0
25
50
TEMPERATURE (°C)
100
125
V
REF
vs Temperature
2.5
V
+
= 5V
COMPARATOR HYSTERESIS (mV)
VOLTAGE ON I
SET
PIN (V)
2.0
R
SET
= 1M
1.5
1.0
0.5
0.1
–50
–25
U W
1045 G01
I
+
vs R
SET
5
T
A
= 25°C
V
+
= V
OH
= 5V
V
–
= V
OL
= 0V
Delay Time vs R
SET
1.2
1.0
0.8
0.6
0.4
0.2
0
100
T
A
= 25°C
V
+
= V
OH
= 5V
V
–
= V
OL
= 0V
V
IN
= V
TRIP
±100mV
4
3
2
1
0
100
1k
10k
R
SET
(Ω)
100k
1M
1045 G02
1k
10k
R
SET
(Ω)
100k
1M
1045 G03
Hysteresis vs R
SET
20
18
16
14
12
10
8
6
4
2
V
+
= 5V
R
SET
= 10k
75
0
25
50
TEMPERATURE (°C)
100
125
0
100
1k
10k
R
SET
(Ω)
100k
1M
1045 G05
1045 G04
1045fc
3
LTC1045
PIN FUNCTIONS
V
OH
(Pin 1):
High Level to which the Output Switches.
IN1 to IN7 (Pins 2 to 7):
Six Comparator Inputs; Voltage
Range = V
–
to V
–
+ 18V.
V
TRIP2
(Pin 8):
Trip Point for Last Two Comparators
(Inputs 5,6); Voltage Range = V
–
to V
+
– 2V.
V
TRIP1
(Pin 9):
Trip Point for First Four Comparators
(Inputs 1 to 4); Voltage Range = V
–
to V
+
– 2V.
V
–
(Pin 10):
Comparator Negative Supply.
V
OL
(Pin 11):
Low Level to which the Output Switches.
I
SET
(Pin 12):
This has three functions: 1) R
SET
from this
pin to V
–
sets bias current, 2) when forced to V
+
power is
shut off completely and 3) when forced to V
+
outputs are
latched.
DISABLE (Pin 13):
When high, outputs are Hi-Z.
OUT6 to OUT1 (Pins 14 to 19):
Six Driver Outputs.
V
+
(Pin 20):
Comparator Positive Supply.
TEST CIRCUITS
5V
5V
V
IN
+
–
V
+
V
OH
V
OL
OUTPUT
50pF
V
TRIP
= 1.2V
V
–
t
r
1.3V
V
IN
1.2V
1.1V
10%
t
d
5V
OUTPUT
2.5V
0V
90%
90%
Figure 1. Response Time Test Circuit
V
IN
+
–
t
ACC
OUTPUT
V
TRIP
= 1.2V
100mV
V
IN
V
TRIP
–100mV
t
HOLD
5V
I
SET
0V
DISABLE
50%
5V
I
SET
0V
50%
1045 F02
Figure 2. Latch Test Circuit
1045fc
4
U
U
U
t
r
≤
10ns
t
IH
V
+
5V
DISABLE
0V
OUTPUT
10%
90%
50%
t
IH
+
–
10pF
10k
OUTPUTS
5V
90%
t
f
DISABLE
t
r
= t
f
≤
10ns
10%
t
d
V
OL
–5V
1045 F03a
t
r
≤
10ns
t
OH
1045 F01
V
OH
DISABLE
10k
OUTPUT
10%
90%
50%
t
OH
5V
OUTPUTS
V
+
10pF
DISABLE
–5V
10%
1045 F03b
t
r
≤
10ns
90%
DISABLE
50%
10%
t
ACC
5V
OUTPUTS
–5V
1045 F03c
t
SETUP
50pF
Figure 3. Three-State Output Test Circuit
Conditions: V
+
= V
OH
= 5V, V
–
= V
OL
= 0V
LTC1045
BLOCK DIAGRAM
IN1 2
IN2 3
IN3 4
IN4 5
IN5 6
IN6 7
V
TRIP1
9
V
BIAS
BIAS
GENERATOR
W
V
+
20
V
OH
1
V
+
V
OH
+
LEVEL
SHIFT
LATCH
DIS
V
BIAS
V
–
19 OUT1
–
LE
V
OL
V
+
+
–
V
BIAS
V
–
V
OH
18 OUT2
DIS
LE
V
OL
V
OH
17 OUT3
DIS
LE
V
OL
V
OH
16 OUT4
DIS
LE
V
OL
V
+
+
–
V
BIAS
V
–
V
+
+
–
V
BIAS
V
–
V
+
+
–
V
BIAS
V
–
V
+
+
–
V
BIAS
V
–
V
OH
15 OUT5
DIS
LE
V
OL
V
OH
14 OUT6
DIS
LE
V
OL
V
REF
≈
1.6V
∼8k
SHUTDOWN
LATCH
ENABLE
12
I
SET
11
V
OL
1045 BD
13 DISABLE
8
V
TRIP2
10
V
–
R
SET
1045fc
5
嵌入式系统
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
