Maxim MAX909MJA, MAX909CPA, MAX909CSA, MAX909EPA, MAX908MJD Datasheet

...
19-0129; Rev. 3; 7/94
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
_______________General Description
The MAX907/MAX908/MAX909 dual, quad, and single high-speed, ultra low-power voltage comparators are designed for use in systems powered from a single +5V supply; the MAX909 also accepts dual ±5V sup­plies. Their 40ns propagation delay (with 5mV input overdrive) is achieved with a power consumption of only 3.5mW per comparator. The wide input common­mode range extends from 200mV below ground (below the negative supply rail for the MAX909) to within 1.5V of the positive supply rail.
Because they are micropower, high-speed compara­tors that operate from a single +5V supply and include built-in hysteresis, these devices replace a variety of older comparators in a wide range of applications.
MAX907/MAX908/MAX909 outputs are TTL compati­ble, requiring no external pull-up circuitry. All inputs and outputs can be continuously shorted to either sup­ply rail without damage. These easy-to-use compara­tors incorporate internal hysteresis to ensure clean out­put switching even when the devices are driven by a slow-moving input signal.
The MAX909 features complementary outputs and an output latch. A separate supply pin for extending the analog input range down to -5V is also provided.
The dual MAX907 and single MAX909 are available in 8-pin DIP and small-outline packages, and the quad MAX908 is available in 14-pin DIP and small-outline packages. These comparators are ideal for single +5V-supply applications that require the combination of high speed, precision, and ultra-low power dissipation.
_______________________Applications
Battery-Powered Systems High-Speed A/D Converters High-Speed V/F Converters Line Receivers Threshold Detectors/Discriminators High-Speed Sampling Circuits Zero Crossing Detectors
___________________________Features
40ns Propagation Delay700µA (3.5mW) Supply Current per Comparator Single 4.5V to 5.5V Supply Operation
(or ±5V, MAX909 only)
Wide Input Range Includes Ground
(or -5V, MAX909 only)
Low, 500µV Offset VoltageInternal Hysteresis Provides Clean SwitchingTTL-Compatible Outputs
(Complementary on MAX909)
Input and Output Short-Circuit ProtectionInternal Latch (MAX909 only)
______________Ordering Information
PART TEMP. RANGE PIN-PACKAGE
MAX907CPA
MAX907CSA 0°C to +70°C 8 SO MAX907C/D 0°C to +70°C Dice* MAX907EPA -40°C to +85°C 8 Plastic DIP MAX907ESA -40°C to +85°C 8 SO MAX907MJA -55°C to +125°C 8 CERDIP
Ordering Information continued on last page.
* Dice are specified at +25°C, DC parameters only.
0°C to +70°C 8 Plastic DIP
_________________Pin Configurations
TOP VIEW
Pin Configurations continued on last page.
OUTA
GND
OUTA
INB+
OUTB
1 2 3 4
MAX907
DIP/SO
1 2 3 4
V+
MAX908
5 6 7
DIP/SO
8
V+ OUTB
7
6 5
INB+
14
OUTD IND-
13
IND+
12 11
GND INC+
10
INC-
9 8
OUTC
MAX907/MAX908/MAX909
________________________________________________________________ Maxim Integrated Products
Call toll free 1-800-998-8800 for free samples or literature.
1
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
ABSOLUTE MAXIMUM RATINGS
Positive Supply Voltage (V+ to GND) ........................+7V
Negative Supply Voltage (V- to GND, MAX909 only).........-7V
Differential Input Voltage
MAX907/MAX908..........................-0.3V to (V+ + 0.3V)
MAX909 ..............................(V- - 0.3V) to (V+ + 0.3V)
Common-Mode Input Voltage
MAX907/MAX908..........................-0.3V to (V+ + 0.3V)
MAX909 ..............................(V- - 0.3V) to (V+ + 0.3V)
Latch Input Voltage (MAX909 only).........-0.3V to (V+ + 0.3V)
Input/Output Short-Circuit Duration to V+ or GND . ..Continuous
Continuous Power Dissipation (T
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C)...727mW
8-Pin SO (derate 5.88mW/°C above +70°C) ...........471mW
8-Pin CERDIP (derate 8.00mW/°C above +70°C)......640mW
14-Pin Plastic DIP (derate 10.00mW/°C above +70°C) . ..800mW
14-Pin SO (derate 8.33mW/°C above +70°C)..........667mW
14-Pin CERDIP (derate 9.09mW/°C above +70°C) ....727mW
Operating Temperature Ranges:
MAX90_C_ _ ...................................... 0°C to +70°C
MAX90_E_ _ ...................................-40°C to +85°C
MAX90_MJ_ ..................................-55°C to +125°C
Storage Temperature Range ...................-65°C to +160°C
Lead Temperature (soldering, 10sec)....................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V+ = 5V, TA= +25°C; MAX909 only: V- = 0V, V
MAX907/MAX908/MAX909
PARAMETER CONDITIONS MIN TYP MAX UNITS
Positive Trip Point Negative Trip Point Input Offset Voltage Input Bias Current Input Offset Current
Input Voltage Range
SYMBOL
V
TRIP+
V
TRIP-
V
OS
I
B
I
OS
V
CMR
Common-Mode Rejection Ratio CMRR (Notes 4, 5) 50 100 µV/V Power-Supply Rejection Ratio PSRR (Notes 4, 6) 50 100 µV/V Output High Voltage
Positive Supply Current per Comparator
V
OH
V
OL
I+ (Note 7)
Negative Supply Current I- MAX909 only: V- = -5V 60 100 µA Power Dissipation per
Comparator Output Rise Time
Output Fall Time
PD (Note 8)
t
r
t
f
= 0V; unless otherwise noted.)
LATCH
(Note 1) 24 mV (Note 1) -2 -4 mV (Note 2) 0.5 2.0 mV VCM= 0V, VIN= V VCM= 0V, VIN= V
(Notes 3, 4)
I
SOURCE
I
= 3.2mA
SINK
I
= 8mA
SINK
OS OS
MAX907/908/909 MAX909 only: V- = -5V
= 100µA
-0.2 V+ - 1.5
-5.2 V+ - 1.5
3.0 3.5
MAX907/MAX908 MAX909
MAX907/MAX908 MAX909
V
= 0.4V to 2.4V, CL= 10pF
OUT
V
= 2.4V to 0.4V, CL= 10pF
OUT
= +70°C)
A
100 300 nA
25 50 nA
0.3 0.4
0.4
0.7 1.0
1.2 1.8
3.5 5.5 610
12 ns
6 ns
V
V VOutput Low Voltage
mA
mW
2 _______________________________________________________________________________________
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 5V, TA= +25°C; MAX909 only: V- = 0V, V
PARAMETER
Propagation Delay
SYMBOL CONDITIONS MIN TYP MAX UNITS
t
PD+,tPD-
Differential Propagation Delay
Propagation Delay Skew
tPDskew
Latch Input Voltage High Latch Input Voltage Low Latch Input Current
IIH, I Latch Setup Time Latch Hold Time
ELECTRICAL CHARACTERISTICS
(V+ = 5V, TA= T
Positive Trip Point Negative Trip Point Input Offset Voltage Input Bias Current Input Offset Current
Input Voltage Range
Common-Mode Rejection Ratio CMRR (Notes 4, 5) 75 200 µV/V Power-Supply Rejection Ratio PSRR (Notes 4, 6) 75 200 µV/V Output High Voltage
Positive Supply Current per Comparator
Negative Supply Current I- MAX909 only: V- = -5V 100 200 µA Power Dissipation per Comparator PD (Note 8)
to T
MIN
MAX
PARAMETER
; MAX909 only: V- = 0V, V
SYMBOL CONDITIONS MIN TYP MAX UNITS
V
V
V
= 0V; unless otherwise noted.)
LATCH
VIN= 100mV, VOD= 5mV, (Note 9)
t
VIN= 100mV, VOD= 5mV,
PD
(Note 10) MAX909 only: VIN= 100mV,
= 5mV, (Note 11)
V
OD
V V
TRIP+
TRIP-
V
I
I
(Note 12) 2.0 V
IH
(Note 12) 0.8 V
IL
(Note 12) 20 µA
IL
t
(Note 12) 2 ns
s
t
(Note 12) 2 ns
h
= 0V; unless otherwise noted.)
LATCH
(Note 1) 25 mV (Note 1) -2 -5 mV (Note 2) 13 mV
OS
VCM= 0V, VIN= V
B
VCM= 0V, VIN= V
OS
C/E temp. ranges (Notes 3, 4)
CMR
M temp. range (Notes 3, 4)
V V
I
SOURCE
I
SINK
I
SINK
= 100µA = 3.2mA = 8mA
OH
OL
I+ (Note 7)
OS OS
MAX909 only, V- = -5V
MAX907/908/909 MAX909 only,
V- = -5V
MAX907/MAX908 MAX909
MAX907/MAX908 MAX909
40 50 ns
1 ns
2 ns
200 500 nA
50 100 nA
-0.2 V+ - 1.5MAX907/908/909
-5.2 V+ - 1.5
-0.1 V+ - 1.5
-5.1 V+ - 1.5
2.8 3.5
0.3 0.4
0.4
0.8 1.2
1.2 2.0
47 611
V
V VOutput Low Voltage
mA
mW
MAX907/MAX908/MAX909
_______________________________________________________________________________________ 3
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 5V, TA= T
Propagation Delay
Differential Propagation Delay
Propagation Delay Skew Latch Input Voltage High
Latch Input Voltage Low Latch Input Current Latch Setup Time Latch Hold Time
Note 1: Trip Point is defined as the input voltage required to make the comparator output change state. The difference
Note 2: Input Offset Voltage is defined as the center of the input-referred hysteresis zone. Specified for V Note 3: Inferred from the CMRR test. Note that a correct logic result is obtained at the output, provided that at least one input is
MAX907/MAX908/MAX909
Note 4: Tested with V+ = 5.5V (and V- = 0V for MAX909). MAX909 also tested over the full analog input range (i.e., with
Note 5: Tested over the full input voltage range (V Note 6: Specified over the full tolerance of operating supply voltage: MAX907/MAX908 tested with 4.5V < V+ < 5.5V. MAX909
Note 7: Positive Supply Current specified with the worst-case condition of all outputs at logic low (MAX907/MAX908), and
Note 8: Typical power specified with V+ = 5V; maximum with V+ = 5.5V (and with V- = -5.5V for MAX909). Note 9: Due to difficulties in measuring propagation delay with 5mV of overdrive in automatic test equipment, the
Note 10: Differential Propagation Delay is specified as the difference between any two channels in the MAX907/MAX908 (both out-
Note 11: Propagation Delay Skew is specified as the difference between any single channel’s output low-to-high transition (t
Note 12: Latch specifications apply to MAX909 only. See Figure 2.
to T
MIN
PARAMETER
; MAX909 only: V- = 0V, V
MAX
SYMBOL CONDITIONS MIN TYP MAX UNITS
t
PD+,tPD-
t
PD
tPDskew
V
IH
V
IL
IIH, I
IL
t
s
t
h
between upper (V
+) and lower (V
TRIP
TRIP
Specified for an input common-mode voltage (V
within the V
limits. Note also that either or both inputs can be driven to the upper or lower absolute maximum limit with-
CMR
= 0V; unless otherwise noted.)
LATCH
VIN= 100mV, VOD= 5mV (Note 9)
VIN= 100mV, VOD= 5mV (Note 10)
MAX909 only: VIN= 100mV,
= 5mV (Note 11)
V
OD
45 70 ns
2 ns
4 ns
(Note 12) 2.0 V (Note 12) 0.8 V (Note 12) 20 µA (Note 12) 4 ns (Note 12) 4 ns
-) trip points is equal to the width of the input-referred hysteresis zone (V ) of 0V. See Figure 1.
CM
= 0V. See Figure 1.
CM
out damage to the part.
V- = -5.5V).
).
CMR
tested with 4.5V < V+ < 5.5V and with -5.5V < V- < 0V.
with V+ = 5.5V.
MAX907/MAX908/MAX909 are sample tested to 0.1% AQL with 100mV input overdrive. Correlation tests show that the specification can be guaranteed if all other DC parameters are within the specified limits. V
must be added to the over-
OS
drive voltage for low values of overdrive.
puts making either a low-to-high or a high-to-low transition).
and high-to-low transition (t
-), and also between the QOUT and QOUT transition on the MAX909.
PD
HYST
).
+)
PD
4 _______________________________________________________________________________________
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
__________________________________________Typical Operating Characteristics
(V+ = 5V, TA= +25°C, unless otherwise noted.)
MAX907/MAX908/MAX909
PROPAGATION DELAY
50
40
30
20
PROPAGATION DELAY (ns)
10
70
60
50
40
PROPAGATION DELAY (ns)
30
2.0
1.5
(mA)
CC
1.0
TOTAL I
0.5
vs. INPUT OVERDRIVE
RS = 10Ω
= 15pF
C
LOAD
tPD+ tPD-
1 10 100
INPUT OVERDRIVE (mV)
PROPAGATION DELAY
vs. TEMPERATURE
VOD = 5mV
= 10Ω
R
S
= 15pF
C
LOAD
-60 -20 60 140
-40 0 8040 120
TOTAL POSITIVE SUPPLY CURRENT
20 100
TEMPERATURE (°C)
MAX907
vs. POSITIVE SUPPLY VOLTAGE
(OUTPUTS AT V
TA = +125°C
TA = +25°C
TA = -55°C
PROPAGATION DELAY
80
60
40
20
PROPAGATION DELAY (ns)
5.0
4.5
tPD+ t
-
PD
)
OL
(V)
4.0
OH
V
3.5
3.0
2.0
1.5
(mA)
CC
1.0
TOTAL I
0.5
vs. SOURCE IMPEDANCE
VOD = 5mV
= 15pF
C
LOAD
tPD+ tPD-
0
10 100 10k
SOURCE IMPEDANCE ()
OUTPUT HIGH VOLTAGE
vs. SOURCE CURRENT
VIN = 100mV
TA = +125°C
TA = +25°C
TA = -55°C
1 10 1000
TOTAL POSITIVE SUPPLY CURRENT
vs. POSITIVE SUPPLY VOLTAGE
(OUTPUTS AT V
I
SOURCE
MAX907
TA = +125°C
TA = +25°C
TA = -55°C
(µA)
100
1k
)
OH
70
60
50
40
PROPAGATION DELAY (ns)
30
0.5
0.4
(V)
0.3
OL
V
0.2
0.1
4.0
3.0
(mA)
CC
2.0
TOTAL I
1.0
PROPAGATION DELAY
vs. CAPACITIVE LOAD
VOD = 5mV
= 10
R
S
tPD+
tPD-
0 120
20 60 100
40
CAPACITIVE LOAD (pF)
OUTPUT LOW VOLTAGE
vs. SINK CURRENT
VIN = 100mV
TA = +25°C
TA = +125°C
012
2610
4
TOTAL POSITIVE SUPPLY CURRENT
vs. POSITIVE SUPPLY VOLTAGE
(OUTPUTS AT V
= -55°C
T
A
I
(mA)
SINK
MAX908
TA = +125°C
80
8
)
OL
TA = +25°C
TA = -55°C
0
28
357
4
6
V
(V)
CC
0
28
357
_________________________________________________________________________________________________
0
28
4
6
V
(V)
CC
357
4
6
V
(V)
CC
5
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
____________________________Typical Operating Characteristics (continued)
(V+ = 5V, TA= +25°C, unless otherwise noted.)
TOTAL POSITIVE SUPPLY CURRENT
4.0
3.0
(mA)
CC
2.0
TOTAL I
1.0
0
28
5
MAX907/MAX908/MAX909
4
0
INPUT VOLTAGE RANGE (V)
-1
-60 -20 60 140
-40 0 8040 120
MAX908
vs. POSITIVE SUPPLY VOLTAGE
(OUTPUTS AT V
TA = +125°C
357
4
INPUT VOLTAGE RANGE
vs. TEMPERATURE
20 100
TEMPERATURE (°C)
)
OH
TA = +25°C
TA = -55°C
6
V
(V)
CC
V
CMR+
V
CMR-
MAX909
POSITIVE SUPPLY CURRENT 
vs. POSITIVE SUPPLY VOLTAGE
2.0
V- = -5V
1.0
TOTAL I+ (mA)
0
23 5 8
5
4
-5
INPUT VOLTAGE RANGE (V)
-6
-60 -20 60 140
46
MAX909
INPUT VOLTAGE RANGE
vs. TEMPERATURE
20 100
-40 40 120080 TEMPERATURE (°C)
V+ (V)
MAX909
NEGATIVE SUPPLY CURRENT 
vs. NEGATIVE SUPPLY VOLTAGE
200
V+ = +5V
+125°C
+25°C
-55°C
7
V
+
CMR
V+ = +5V V- = -5V
V
-
CMR
100
TOTAL I- (µA)
0
0-1 -3 -6
-2 -4 V- (V)
SHORT-CIRCUIT OUTPUT CURRENT
60
30
SHORT-CIRCUIT OUTPUT CURRENT (mA)
0
vs. TEMPERATURE
OUTPUT SHORTED TO V+ (SINKING)
-60 -20 60 140
20 100
-40 0 8040 120 TEMPERATURE (°C)
+125°C
+25°C
-55°C
-5 -7
OUTPUT
SHORTED TO
GND (SOURCING)
INPUT OFFSET VOLTAGE
0.5
(mV)
0
OS
V
-0.5
6
________________________________________________________________________________________________
vs. TEMPERATURE
V
= 1.4V
OUT
= 0V
V
CM
-60 -20 60 140
-40 0 8040 120
20 100
TEMPERATURE (°C)
300
200
INPUT CURRENT (nA)
100
INPUT BIAS CURRENT
vs. TEMPERATURE
VCM = 0V
= V
V
IN
OS
-60 -20 60 140
-40 0 8040 120
20 100
TEMPERATURE (°C)
4
VCM = 0V
2
(mV)
0
OS
V
-2
-4
-60 -20 60 140
-40 0 8040 120
TRIP POINT
vs. TEMPERATURE
V
TRIP+
V
TRIP-
20 100
TEMPERATURE (°C)
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
____________________________Typical Operating Characteristics (continued)
(V+ = 5V, TA= +25°C, unless otherwise noted.)
MAX907/MAX908/MAX909
INPUT
(20mV/div)
INPUT
(20mV/div)
OUTPUT
GND
PROPAGATION DELAY (t
PROPAGATION DELAY (t
 
MAX907/MAX908
(5mV OVERDRIVE)
tPD+
 
MAX909
(5mV OVERDRIVE)
tPD+
+)
PD
+)
PD
tPD SKEW
5mV OVERDRIVE INPUT GND
OUTPUT (500mV/div)
TTL  THRESHOLD (1.4V) 
OUTPUT GND
5mV OVERDRIVE INPUT GND
QOUT (1V/div)
1.4V QOUT
  
RESPONSE TO 10MHz SINE WAVE
INPUT
(20mV/div)
INPUT
(20mV/div)
OUTPUT
GND
PROPAGATION DELAY (t
PROPAGATION DELAY (t
 
MAX907/MAX908
(5mV OVERDRIVE)
tPD-
 
MAX909
(5mV OVERDRIVE)
tPD- tPD SKEW
-)
PD
INPUT GND
-5mV OVERDRIVE
OUTPUT (500mV/div)
TTL  THRESHOLD  (1.4V)
OUTPUT GND
-)
PD
INPUT GND
-5mV OVERDRIVE
QOUT (1V/div)
1.4V QOUT
20mVp-p
10MHz SINE WAVE
INPUT
COMPARATOR
OUTPUT
(1V/div) GND
TIME (50ns/div)
_________________________________________________________________________________________________
7
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
______________________________________________________________Pin Description
PIN
MAX907 MAX908 MAX909
1 1 OUTA Comparator A Output 2 2 INA- Comparator A Inverting Input 3 3 INA+ Comparator A Noninverting Input 8 4 1 V+ Positive Supply 5 5 INB+ Comparator B Noninverting Input 6 6 INB- Comparator B Inverting Input 7 7 OUTB Comparator B Output
8 OUTC Comparator C Output 9 INC- Comparator C Inverting Input
10 INC+ Comparator C Noninverting Input
4 11 6 GND Ground
12 IND+ Comparator D Noninverting Input 13 IND- Comparator D Inverting Input 14 OUTD Comparator D Output
2 IN+ Noninverting Input 3 IN- Inverting Input
MAX907/MAX908/MAX909
4 V- Negative Supply or Ground
5 LE
7 QOUT Comparator Output 8
NAME FUNCTION
The latch is transparent when LE is low. The comparator output is stored when LE is high.
QOUT
Inverted Comparator Output
_______________Detailed Description
Timing
Noise or undesired parasitic AC feedback cause most high-speed comparators to oscillate in the linear region (i.e., when the voltage on one input is at or near the voltage on the other input). The MAX907/MAX908/ MAX909 eliminate this problem by incorporating inter­nal hysteresis. When the two comparator input volt­ages are equal, hysteresis effectively causes one com­parator input voltage to move quickly past the other, thus taking the input out of the region where oscillation occurs. Standard comparators require that hysteresis be added through the use of external resistors. The MAX907/MAX908/MAX909’s fixed internal hysteresis eliminates these resistors (and the equations required to determine appropriate values).
8 _______________________________________________________________________________________
Adding hysteresis to a comparator creates two trip points: one for the input voltage rising and one for the input voltage falling (Figure 1). The difference between these two input-referred trip points is the hysteresis.
Figure 1 illustrates the case where IN- is fixed and IN+ is varied. If the inputs were reversed, the figure would look the same, except the output would be inverted.
The MAX909 includes an internal latch, allowing the result of a comparison to be stored. If LE is low, the latch is transparent (i.e., the comparator operates as though the latch is not present). The state of the com­parator output is stored when LE is high. See Figure 2.
Note that the MAX909 can be operated with V- con­nected to ground or to a negative supply voltage. The MAX909’s input range extends from (V- - 0.2V) to (V+ - 1.5V).
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
V
TRIP+
V
V
HYST
V
TRIP-
COMPARATOR
OUTPUT
IN+
V
+ V
TRIP+
V
=
OS
V
= 0V
IN-
V
V
TRIP-
2
OH
OL
Figure 1. Input and Output Waveforms, Noninverting Input Varied
__________Applications Information
Circuit Layout
Because of the MAX907/MAX908/MAX909’s high gain bandwidth, special precautions must be taken to real­ize the full high-speed capability. A printed circuit board with a good, low-inductance ground plane is mandatory. Place the decoupling capacitor (a 0.1µF ceramic capacitor is a good choice) as close to V+ as possible. Pay close attention to the decoupling capaci­tor’s bandwidth, keeping leads short. Short lead lengths on the inputs and outputs are also essential to avoid unwanted parasitic feedback around the com­parators. Solder the device directly to the printed cir­cuit board instead of using a socket.
Overdriving the Inputs
The inputs to the MAX907/MAX908/MAX909 may be driven beyond the voltage limits given in the
Maximum Ratings
, as long as the current flowing into the device is limited to 25mA. However, if the inputs are overdriven, the output may be inverted. The addi­tion of an external diode prevents this inversion by limit­ing the input voltage to 200mV to 300mV below ground (see Figure 3).
Absolute
3V
LE
1.4V COMPARE
0
V
INPUT
VOLTAGE
OUTPUT
(QOUT)
OUTPUT
Q
OUT)
(
V
1.4V
V
V
1.4V
V
OS
OH
OL
OH
OL
DIFFERENTIAL
Figure 2. MAX909 Timing Diagram
Battery-Operated Infrared Data Link
Figure 4's circuit allows reception of infrared data. The MAX403 converts the photodiode current to a voltage, and the MAX907 determines whether the amplifier output is high enough to be called a “1”. The current consump­tion of this circuit is minimal: The MAX403 and MAX907 require typically 250µA and 700µA, respectively.
LATCH
t
h
t
s
V
OD
V
IN
tPD+
t
SKEW
MAX907/MAX908/MAX909
_______________________________________________________________________________________ 9
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
10pF
1M
V
= -200mV TO -300mV
I
CLAMP
SRC
V-
1/2 MAX907
MAX403
SIEMENS BP-104 PHOTODIODE
100k
1000pF
1000pF
+5V
7
4
100k
0.1µF
6
+5V
2
3
47k
+5V
3
2
0.1µF
8
1
DATA
4
MAX907
Figure 3. Schottky Clamp for Input Driven Below Ground
MAX907/MAX908/MAX909
Figure 4. Battery-Operated Infrared Data Link Consumes Only 1mA
10 ______________________________________________________________________________________
Single/Dual/Quad High-Speed, Ultra Low-Power,
Single-Supply TTL Comparators
____Pin Configurations (continued) _Ordering Information (continued)
PART TEMP. RANGE PIN-PACKAGE
TOP VIEW
IN+
IN-
MAX908CPD
V+
1
MAX909
2 3 4
V-
DIP/SO
8
QOUT QOUT
7
GND
6 5
LE
MAX908CSD 0°C to +70°C 14 SO MAX908EPD -40°C to +85°C 14 Plastic DIP MAX908ESD -40°C to +85°C 14 SO MAX908MJD -55°C to +125°C 14 CERDIP MAX909CPA MAX909CSA 0°C to +70°C 8 SO MAX909C/D 0°C to +70°C Dice* MAX909EPA -40°C to +85°C 8 Plastic DIP MAX909ESA -40°C to +85°C 8 SO MAX909MJA -55°C to +125°C 8 CERDIP
* Dice are specified at +25°C, DC parameters only.
0°C to +70°C 14 Plastic DIP
0°C to +70°C 8 Plastic DIP
MAX907/MAX908/MAX909
______________________________________________________________________________________ 11
Single/Dual/Quad High-Speed, Ultra Low-Power, Single-Supply TTL Comparators
__________________________________________________________Chip Topographies
INB-
MAX907
INB+
MAX909
V+
OUTB
0.057"
V+
OUTA
INA-
INA+
0.055"
(1.40mm)
TRANSISTOR COUNT: MAX907:180  MAX908:360
MAX907/MAX908/MAX909
 SUBSTRATE CONNECTED TO GND.
GND
(1.45mm)
IN+
IN-
V-
0.050"
(1.27mm)
TRANSISTOR COUNT: 95;   SUBSTRATE CONNECTED TO V-.
QOUT
QOUT
GND
LE
0.051"
(1.30mm)
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12
__________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1994 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
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