GS8706
Micro-Power, RRIO, 1.6V, Push-Pull Output Comparator
with Integrated Voltage Reference
Features
2.4uA (Typ) Low Power Consumption
Internal Hysteresis for Clean Switching
Integrated 1.2V Voltage Reference
No Phase Reversal for Overdriven Inputs
Fast, 0.9us Propagation Delay
Operating Temperature: -40°C ~ +85°C
Single-Supply Operation from +1.6V ~ +5.5V
Small Package:
Low Offset Voltage: 3mV (Max)
GS8706 Available in SOT23-6 and SC70-6 Packages
Rail-to-Rail Input and Output
GS8706U Available in SOP-8 and MSOP-8 Packages
CMOS/TTL-Compatible Output
General Description
The GS8706 is ultra-low-power comparator with internal hysteresis, optimized for systems powered from a 3V or 5V supply.
The device features high-speed response, low-power consumption, low offset voltage, and rail-to-rail input and output range.A
1.2V voltage reference is integrated for flexible application.
Propagation delay is 0.9us (100mV overdrive), while supply current is 2.4uA per comparator. The internal input hysteresis
eliminates output switching due to internal input noise voltage. The maximum input offset voltage is 3mV, and the operating
range is from 1.6V to 5.5V.
All devices are specified for the temperature range of -40℃ to +85℃. The GS8706 single is available in Green SC70-6 and
SOT23-6 packages. The GS8706U dual is available in Green SOP-8 and MSOP-8 packages.
Applications
Alarm and Monitoring Circuits
Window Comparators
Peak and Zero-crossing Detectors
IR Receivers
Logic Level Shifting or Translation
Portable Systems
RC Timers
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GS8706
Pin Configuration
Figure 1. Pin Assignment Diagram
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GS8706
Absolute Maximum Ratings
Condition
Min
Max
-0.5V
+7.5V
Analog Input Voltage (IN+ or IN-)
Vss-0.5V
VDD+0.5V
PDB Input Voltage
Vss-0.5V
+7V
-40°C
+85°C
Power Supply Voltage (VDD to Vss)
Operating Temperature Range
Junction Temperature
+160°C
Storage Temperature Range
-55°C
Lead Temperature (soldering, 10sec)
+150°C
+260°C
Package Thermal Resistance (TA=+25℃)
SOP-8, θJA
125°C/W
MSOP-8, θJA
216°C/W
SOT23-6, θJA
190°C/W
ESD Susceptibility
HBM
4KV
MM
300V
Note: Stress greater than those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a
stress rating only and functional operation of the device at these or any other conditions outside those indicated in the operational
sections of this specification are not implied. Exposure to absolute maximum rating conditions for extended periods may affect
reliability.
Package/Ordering Information
PACKAGE
PACKAGE
MARKING
DESCRIPTION
OPTION
INFORMATION
GS8706-CR
SC70-6
Tape and Reel,3000
8706
GS8706-TR
SOT23-6
Tape and Reel,3000
8706
GS8706-TR
SOT23-8
Tape and Reel,3000
706U
GS8706U-SR
SOP-8
Tape and Reel,4000
GS8706U
GS8706U-MR
MSOP-8
Tape and Reel,3000
GS8706U
GS8706U2-SR
SOP-8
Tape and Reel,4000
GS8706U2
GS8706U2-MR
MSOP-8
Tape and Reel,3000
GS8706U2
MODEL CHANNEL ORDER NUMBER
GS8706
Single
GS8706U
Single
GS8706U
Single
GS8706U2
Single
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GS8706
Electrical Characteristics
(At VS = +5V, VCM = 0V, CL = 15pF, and TA = +25℃, unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
TYP
MIN
MAX
UNITS
3
mV
INPUT CHARACTERISTICS
Input Offset Voltage
VOS
VCM = 0V
0.5
Input Bias Current
IB
6
pA
Input Offset Current
IOS
4
pA
Input Hysteresis
Vhys
4
mV
Common-Mode Voltage Range
VCM
-0.1 to +5.6
V
Common-Mode Rejection Ratio
CMRR
VS = 5.5V
VS = 5V, VCM = 0V to 5V
76
63
dB
OUTPUT CHARACTERISTICS
Output Voltage Swing from Rail
Output Short-Circuit Current
VOH
VOL
ISOURCE
ISINK
Vs=5V, IO = 1mA
VS = 5V, Out to VS
Vs - 0.1
Vs - 0.3
V
114.6
300
mV
22
mA
20
POWER SUPPLY
Operating Voltage Range
Power Supply Rejection Ratio
Quiescent Current / Comparator
PSRR
VS = +1.6V to +5.5V, VCM = 0V
IQ
1.6
V
5.5
V
102
74
2.4
dB
4.0
uA
DYNAMIC PERFORMANCE (CL = 15pF)
Propagation Delay (Low to High)
Propagation Delay (High to Low)
Rise Time
Fall Time
TdLH
TdHL
Tr
Tf
VS = 3V, Overdrive = 10mV
1.0
μs
VS = 3V, Overdrive = 100mV
0.9
μs
VS = 3V, Overdrive = 10mV
1.2
μs
VS = 3V, Overdrive = 100mV
0.6
μs
VS = 3V, Overdrive = 10mV
16
ns
VS = 3V, Overdrive = 100mV
16
ns
VS = 3V, Overdrive = 10mV
15
ns
VS = 3V, Overdrive = 100mV
15
ns
Voltage Reference
Reference Voltage
Reference Voltage
Reference Output Current
Vref
Iref=0A
1214
1190
1238
mV
150
µV/℃
4
mA
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GS8706
Typical Performance characteristics
At TA=+25oC, VS=+5V, and CL=15pF, unless otherwise noted.
Reference Voltage vs. Temperature
Vref(2mV/div)
IQ(250nA/div)
Supply Current vs. Temperature
temperature(25oC/div)
temperature(25oC/div)
Output Short-Circuit (Source) Current vs. Temperature
ISOURCE(2.5mA/div)
ISINK(2.5mA/div)
Output Short-Circuit (Sink) Current vs. Temperature
temperature(25oC/div)
o
temperature(25 C/div)
Progation Delay (L-H&H-L)
VOUT(0.5V/div)
VOUT(0.5V/div)
VIN(5mV/div)
VIN(50mV/div)
Progation Delay (L-H&H-L)
Time(2us/div)
Time(2us/div)
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GS8706
Application Note
Size
GS8706 comparator is ultra-low-power, high-speed and suitable for a wide range of general-purpose applications. The small
footprints of the GS8706 package saves space on printed circuit boards and enable the design of smaller electronic products.
The GS8706 interfaces directly to CMOS and TTL logics.
Power Supply Bypassing and Board Layout
GS8706 operates from a single 1.6V to 5.5V supply or dual ±0.8V to ±2.75V supplies. For best performance, a 0.1μF ceramic
capacitor should be placed close to the VDD pin in single supply operation. For dual supply operation, both VDD and VSS
supplies should be bypassed to ground with separate 0.1μF ceramic capacitors.
Low Supply Current
The low supply current (typical 2.4uA per channel) of GS8706 will help to maximize battery life. They are ideal for battery
powered systems.
Operating Voltage
GS8706 operates under wide input supply voltage (1.6V to 5.5V). In addition, all temperature specifications apply from -40 oC
to +85 oC. Most behavior remains unchanged throughout the full operating voltage range. These guarantees ensure operation
throughout the single Li-Ion battery lifetime
Rail-to-Rail Input
The input common-mode range of GS8706 extends 100mV beyond the supply rails (VSS-0.1V to VDD+0.1V). This is achieved
by using complementary input stage. For normal operation, inputs should be limited to this range.
Internal Hysteresis
Because of noise or undesired parasitic feedback, high-speed comparators oscillate in the linear region. Oscillation tends to
occur when the voltage on one input is at or equal to the voltage on the other input. The GS806 family eliminates this undesired
oscillation by integrating an internal hysteresis of 4mV.
The hysteresis in a comparator creates two trip points: one for the rising input voltage and one for the falling input voltage (Figure
2). The difference between two trip points is the hysteresis, while the average of two trip points is the offset voltage. When the
comparator’s input voltages are equal, the hysteresis effectively causes one comparator input voltage to move quickly past the
other, thus taking the input out of the region where oscillation occurs.
Figure 2. Comparator’s hysteresis and offset
External Hysteresis
Greater flexibility in selecting hysteresis is achieved by using external resistors. Hysteresis reduces output chattering when one
input is slowly moving past the other.
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GS8706
Non-Inverting Comparator with Hysteresis
Figure 3. Non-Inverting Comparator with Hysteresis
A non-inverting comparator with hysteresis requires a two-resistor network, as shown in Figure 3 and a voltage reference (VR) at
the inverting input.
VTH
RG RF
VR
RF
VTL
RG RF
R
VR G VDD
RF
RF
VHYS
RG
VDD
RF
Inverting Comparator with Hysteresis
VDD
RF
RG1
+
VOUT
RG2
VIN
-
Figure 4. Inverting Comparator with Hysteresis
The inverting comparator with hysteresis requires a three-resistor network that is referenced to the comparator supply voltage
(VDD), as shown in Figure 4.
VTH
RG2
VDD
RG1 || RF RG2
VTL
RG2 || RF
VDD
RG2 || RF RG1
VHYS
RG1 || RG2
VDD
RG1 || RG2 RF
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GS8706
Typical Application Circuits
Line Receiver
A Line Receiver using GS8706 is shown in Figure 5. Resistors RG1 and RG2 set the bias point at the comparator's inverting
input. RIN should be same as RG1||RG2 to get a better match. GS8706 detects the voltage of the Coax Line, and outputs logic
high or logic low quickly with no glitch.
Figure 5. Line Receiver
IR Receiver
GS8706 is an ideal candidate to be used as an infrared receiver shown in Figure 6. The infrared photo diode creates a current
relative to the amount of infrared light present. The current creates a voltage across RIN. When this voltage level cross the
voltage applied by the voltage divider to the inverting input, the output transitions. Optional RF provides additional hysteresis for
noise immunity.
Figure 6. IR Receiver
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GS8706
Oscillator
A oscillator using GS8706 is shown in Figure 7. Resistors RG1 and RG2 set the bias point at the comparator's inverting input.
The period of oscillator is set by the time constant of RC and CIN. The maximum frequency is limited by the large signal
propagation delay of the comparator. GS8706 is low propagation delay guarantees the high frequency oscillation.
If RG1=RG2= RF, then the frequency of the oscillator is:
f OSC
1
2 ln 2 RC CIN
Figure 7. Oscillator
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GS8706
Package Information
SOT23-6
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GS870
06
SC
C70-6
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ptember 2021-REV_V
V1
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13
GS8706
MSOP-8
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GS8706
SOP-8
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