TOUCHSTONE TSM9120

TSM9117-TSM9120
1.6V Nanopower Comparators with/without Internal References
FEATURES
DESCRIPTION
♦ Second-source for MAX9117-MAX9120
♦ Guaranteed to Operate Down to +1.6V
♦ Ultra-Low Supply Current
350nA - TSM9119/TSM9120
600nA - TSM9117/TSM9118
♦ Internal 1.252V ±1.75% Reference
♦ Input Voltage Range Extends 200mV Outside-the-Rails
♦ No Phase Reversal for Overdriven Inputs
♦ Push-pull and Open-Drain Output Versions Available
♦ Crowbar-Current-Free Switching
♦ Internal Hysteresis for Clean Switching
♦ 5-pin SC70 and 8-pin SOIC Packaging
The TSM9117–TSM9120 family of nanopower
comparators is electrically and form-factor identical to
the
MAX9117-MAX9120
family
of
analog
comparators. Ideally suited for all 2-cell batterymanagement/monitoring applications, these 5-pin
SC70 analog comparators guarantee +1.6V
operation, draw very little supply current, and have
robust input stages that can tolerate input voltages
beyond the power supply. The TSM9117 and the
TSM9118 draw 600nA of supply current and include
an on-board 1.252V ±1.75% reference. The
comparator-only TSM9119 and the TSM9120 draw a
supply current of 350nA.
APPLICATIONS
2-Cell Battery Monitoring/Management
Medical Instruments
Threshold Detectors/Discriminators
Sensing at Ground or Supply Line
Ultra-Low-Power Systems
Mobile Communications
Telemetry and Remote Systems
The TSM9117 and TSM9119’s push-push output
drivers were designed to drive 5mA loads from one
supply rail to the other supply rail. The TSM9118 and
the TSM9120’s open-drain output stages make it
easy to incorporate these comparators into systems
that operate on different supply voltages.
TYPICAL APPLICATION CIRCUIT
PART
The Touchstone Semiconductor logo is a registered
trademark of Touchstone Semiconductor, Incorporated.
TSM9117
TSM9118
TSM9119
TSM9120
INTERNAL
REFERENCE
Yes
Yes
No
No
OUTPUT
TYPE
Push-Pull
Open-Drain
Push-Pull
Open-Drain
SUPPLY
CURRENT (nA)
600
600
350
350
Page 1
© 2011 Touchstone Semiconductor, Inc. All rights reserved.
TSM9117-TSM9120
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VCC to VEE) ............................................ +6V
Voltage Inputs (IN+, IN-, REF) .... (VEE - 0.3V) to (VCC + 0.3V)
Output Voltage
TSM9117/9119 ........................ (VEE - 0.3V) to (VCC + 0.3V)
TSM9118/9120 ...................................... (VEE - 0.3V) to +6V
Current Into Input Pins ................................................ ±20mA
Output Current ............................................................ ±50mA
Output Short-Circuit Duration ............................................ 10s
Continuous Power Dissipation (TA = +70°C)
5-Pin SC70 (Derate 2.5mW/°C above +70°C) ........ 200mW
8-Pin SOIC (Derate 5.88mW/°C above +70°C) ...... 471mW
Operating Temperature Range ...................... -40°C to +85°C
Junction Temperature ................................................ +150°C
Storage Temperature Range ....................... -65°C to +150°C
Lead Temperature (soldering, 10s) ............................... +300°
Electrical and thermal 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 condition beyond those indicated in the operational sections
of the specifications is not implied. Exposure to any absolute maximum rating conditions for extended periods may affect device reliability and
lifetime.
PACKAGE/ORDERING INFORMATION
ORDER NUMBER
PART
CARRIER QUANTITY ORDER NUMBER
MARKING
TAA
Tape
& Reel
3000
TSM9118EXK+T
TAB
Tape
& Reel
3000
TSM9119EXK+T
TAC
Tape
& Reel
3000
TAD
Tape
& Reel
3000
TSM9117EXK+T
TSM9120EXK+T
PART
CARRIERQUANTITY
MARKING
TSM9117ESA+
Tube
97
TSM9117ESA+T
Tape
& Reel
2500
TSM9120ESA+
Tube
97
Tape
& Reel
2500
TS9117E
TS9120E
TSM9120ESA+T
Lead-free Program: Touchstone Semiconductor supplies only lead-free packaging.
Consult Touchstone Semiconductor for products specified with wider operating temperature ranges.
Page 2
TSM9117_20DS r1p0
RTFDS
TSM9117-TSM9120
ELECTRICAL CHARACTERISTICS: TSM9117 & TSM9118
VCC = +5V, VEE = 0V, VIN+ = VREF, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.
See Note 1.
PARAMETER
SYMBOL
Supply Voltage Range
VCC
Supply Current
ICC
IN+ Voltage Range
VIN+
Input Offset Voltage
VOS
Input-Referred Hysteresis
VHB
Input Bias Current
Power-Supply Rejection Ratio
Output-Voltage Swing High
Output-Voltage Swing Low
Output Leakage Current
IB
PSRR
VCC - VOH
VOL
ILEAK
Output Short-Circuit Current
ISC
High-to-Low Propagation Delay
(Note 4)
tPD-
Low-to-High Propagation Delay
(Note 4)
tPD+
Rise Time
Fall Time
tRISE
tFALL
Power-Up Time
tON
Reference Voltage
VREF
CONDITIONS
Inferred from the
PSRR test
VCC = 1.6V
TA = +25°C
TA = TMIN to TMAX
TA = +25°C
TA = +25°C
VCC = 5V
TA = TMIN to TMAX
Inferred from the output swing test
TA = +25°C
(Note 2)
TA = TMIN to TMAX
(Note 3)
TA = +25°C
TA = TMIN to TMAX
VCC = 1.6V to 5.5V, TA = +25°C
VCC = 1.8V to 5.5V, TA = TMIN to TMAX
TA = +25°C
TSM9117, VCC = 5V,
ISOURCE = 5mA
TA = TMIN to TMAX
VCC = 1.6V,
TA = +25°C
TSM9117,
ISOURCE = 1mA
VCC = 1.8V,
TA = TMIN to TMAX
TA = +25°C
VCC = 5V, ISINK = 5mA
TA = TMIN to TMAX
VCC = 1.6V,
TA = +25°C
ISINK = 1mA
VCC = 1.8V,
TA = TMIN to TMAX
TSM9118 only, VO = 5.5V
VCC = 5V
Sourcing, VO = VEE
VCC = 1.6V
VCC = 5V
Sinking, VO = VCC
VCC = 1.6V
VCC = 1.6V
VCC = 5V
VCC = 1.6V
TSM9117 only
VCC = 5V
VCC = 1.6V,
RPULLUP = 100kΩ
TSM9118 only
VCC = 5V,
RPULLUP = 100kΩ
TSM9117 only, CL = 15pF
CL = 15pF
∆VREF/ ∆VCC
Reference Load Regulation
∆VREF/ ∆IOUT ∆IOUT = 10nA
TSM9117_20DS r1p0
TYP
0.6
0.68
VEE - 0.2
1
4
0.15
0.1
190
100
MAX
5.5
5.5
1
1.30
1.60
VCC + 0.2
5
10
BW = 10Hz to 100kHz
BW = 10Hz to 100kHz, CREF = 1nF
VCC = 1.6V to 5.5V
V
μA
V
mV
mV
mV/V
mV/V
200
mV
nA
300
190
400
500
100
200
mV
300
0.002
35
3
35
3
16
14
15
40
1
μA
mA
µs
µs
16
45
1.6
0.2
1.230
1.196
1.252
100
TCVREF
UNITS
1
2
1
1
400
500
µs
µs
1.2
TA = +25°C
TA = TMIN to TMAX
Reference Voltage
Temperature Coefficient
Reference Output Voltage
Noise
Reference Line Regulation
en
MIN
1.6
1.8
1.1
0.2
0.25
±1
ms
1.274
1.308
V
ppm/°C
mVRMS
mV/V
mV/nA
Page 3
RTFDS
TSM9117-TSM9120
ELECTRICAL CHARACTERISTICS: TSM9119 & TSM9120
VCC = +5V, VEE = 0V, VCM = 0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.
See Note 1.
PARAMETER
SYMBOL
Supply Voltage Range
VCC
Supply Current
ICC
Input Common-Mode Voltage
Range
VCM
Input Offset Voltage
VOS
Input-Referred Hysteresis
VHB
Input Bias Current
IB
Input Offset Current
IOS
Power-Supply Rejection Ratio
PSRR
Common-Mode Rejection Ratio
CMRR
Output-Voltage Swing High
VCC - VOH
Output-Voltage Swing Low
VOL
Output Leakage Current
ILEAK
Output Short-Circuit Current
ISC
High-to-Low Propagation Delay
(Note 4)
tPD-
Low-to-High Propagation Delay
(Note 4)
tPD+
Rise Time
Fall Time
tRISE
tFALL
Power-Up Time
tON
CONDITIONS
Inferred from the
PSRR test
VCC = 1.6V
VCC = 5V
TA = +25°C
TA = TMIN to TMAX
TA = +25°C
TA = +25°C
TA = TMIN to TMAX
Inferred from the CMRR test
TA = +25°C
-0.2V ≤ VCM ≤ (VCC+0.2V)
(Note 2)
TA = TMIN to TMAX
-0.2V ≤ VCM ≤ (VCC+0.2V) (Note 3)
TA = +25°C
TA = TMIN to TMAX
VCC = 1.6V to 5.5V, TA = +25°C
VCC = 1.8V to 5.5V, TA = TMIN to TMAX
(VEE - 0.2V) ≤ VCM ≤ (VCC + 0.2V)
TA = +25°C
TSM9119 only, VCC = 5V,
ISOURCE = 5mA
TA = TMIN to TMAX
VCC = 1.6V,
TA = +25°C
TSM9119 only,
ISOURCE = 1mA
VCC = 1.8V,
TA = TMIN to TMAX
TA = +25°C
VCC = 5V, ISINK = 5mA
TA = TMIN to TMAX
VCC = 1.6V,
TA = +25°C
ISINK = 1mA
VCC = 1.8V,
TA = TMIN to TMAX
TSM9120 only, VO = 5.5V
VCC = 5V
Sourcing, VO = VEE
VCC = 1.6V
VCC = 5V
Sinking, VO = VCC
VCC = 1.6V
VCC = 1.6V
VCC = 5V
VCC = 1.6V
TSM9119 only
VCC = 5V
VCC = 1.6V,
RPULLUP = 100kΩ
TSM9120 only
VCC = 5V,
RPULLUP = 100kΩ
TSM9119 only, CL = 15pF
CL = 15pF
MIN
1.6
1.8
TYP
0.35
0.45
VEE - 0.2
1
4
0.15
75
0.1
0.5
190
100
MAX
5.5
5.5
0.80
0.80
1.20
UNITS
VCC + 0.2
V
5
10
mV
V
μA
mV
1
2
1
1
3
400
500
200
nA
pA
mV/V
mV/V
mV/V
mV
300
190
400
500
100
200
mV
300
0.001
35
3
35
3
16
14
15
40
16
1
μA
mA
µs
µs
45
1.6
0.2
µs
µs
1.2
ms
Note 1: All specifications are 100% tested at TA = +25°C. Specification limits over temperature (TA = TMIN to TMAX) are guaranteed by
design, not production tested.
Note 2: VOS is defined as the center of the hysteresis band at the input.
Note 3: The hysteresis-related trip points are defined by the edges of the hysteresis band, measured with respect to the center of the
hysteresis band (i.e., VOS) (See Figure 2).
Note 4: Specified with an input overdrive (VOVERDRIVE) of 100mV, and load capacitance of CL = 15pF. VOVERDRIVE is defined above and
beyond the offset voltage and hysteresis of the comparator input. For the TSM9117/TSM9118, reference voltage error should
also be added.
Page 4
TSM9117_20DS r1p0
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
TSM9117/9118 Supply Current vs
TSM9119/9120 Supply Current
Supply Voltage and Temperature
vs Supply Voltage and Temperature
1
1.25
0.9
TA = +85°C
1.05
SUPPLY CURENT - µA
SUPPLY CURENT - µA
1.15
0.95
0.85
0.75
TA = +25°C
0.65
0.55
TA = -40°C
TA = +85°C
0.8
0.7
0.6
0.5
TA = +25°C
0.4
TA = -40°C
0.3
0.45
0.2
1.5
2.5
3.5
4.5
5.5
1.5
4.5
5.5
SUPPLY VOLTAGE - Volt
TSM9117/9118 Supply Current vs Temperature
1.1
TSM9119/9120 Supply Current vs Temperature
1
0.9
SUPPLY CURENT - µA
SUPPLY CURENT - µA
3.5
SUPPLY VOLTAGE - Volt
1
VCC =+5V
0.9
0.8
VCC =+3V
0.7
0.6
VCC =+1.8V
0.5
0.8
VCC =+5V
0.7
0.6
VCC =+3V
0.5
0.4
VCC =+1.8V
0.3
0.4
0.2
-40
-15
35
10
60
-40
85
-15
10
35
60
TEMPERATURE - °C
TEMPERATURE - °C
TSM9117/9118 Supply Current
vs Output Transition Frequency
TSM9119/9120 Supply Current
vs Output Transition Frequency
35
35
30
30
SUPPLY CURRENT - µA
SUPPLY CURRENT - µA
2.5
25
VCC =+5V
20
15
VCC =+3V
10
VCC =+1.8V
5
0
85
25
VCC =+5V
20
15
VCC =+3V
10
VCC =+1.8V
5
0
1
10
100
1k
10k
OUTPUT TRANSITION FREQUENCY - Hz
TSM9117_20DS r1p0
1
10
100
1k
10k
OUTPUT TRANSITION FREQUENCY- Hz
Page 5
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
Output Voltage Low
vs. Sink Current and Temperature
Output Voltage Low vs. Sink Current
600
700
TA = +25°C
600
500
VCC =+3V
400
400
VOL - mV
VOL - mV
500
VCC =+1.8V
300
300
TA = +85°C
200
VCC =+5V
200
TA = +25°C
TA = -40°C
100
100
0
0
2
0
4
6
8
10
0
SINK CURRENT- mA
8
10
0.6
0.6
0.5
VCC =+1.8V
VCC =+3V
TA = +25°C
VCC – VOH - V
0.5
VCC – VOH - V
6
TSM9117/9119 Output Voltage High
vs Source Current and Temperature
0.7
0.4
0.3
VCC =+5V
0.2
0.4
0.3
TA = +85°C
0.2
TA = -40°C
0.1
0.1
0
0
0
2
4
6
8
0
10
2
4
6
8
10
SOURCE CURRENT- mA
SOURCE CURRENT- mA
Short-Circuit Sink Current vs Temperature
TSM9117/9119 Short-Circuit Source Current
vs Temperature
50
40
45
35
VCC =+5V
SOURCE CURRENT- mA
SINK CURRENT- mA
4
SINK CURRENT- mA
TSM9117/9119 Output Voltage High
vs Source Current
30
25
20
VCC =+3V
15
10
VCC =+1.8V
5
VCC =+5V
40
35
30
25
VCC =+3V
20
15
10
VCC =+1.8V
5
0
0
-40
-15
10
35
TEMPERATURE - °C
Page 6
2
60
85
-40
-15
10
35
60
85
TEMPERATURE - °C
TSM9117_20DS r1p0
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
Offset Voltage vs Temperature
Hysteresis Voltage vs Temperature
2.8
6
VCC =+1.8V
5.5
2.6
VHB - mV
VOS - mV
5
VCC =+3V
2.4
4.5
4
VCC =+5V
2.2
3.5
2
3
-40
-15
10
35
60
85
-40
-15
35
10
60
TEMPERATURE - °C
TEMPERATURE - °C
TSM9117/9118 Reference Voltage
vs Temperature
TSM9117/9118 Reference Voltage
vs Supply Voltage
1.260
85
1.254
1.256
REFERENCE VOLTAGE - V
REFERENCE VOLTAGE - V
1.258
VCC =+1.8V
1.254
1.252
1.250
VCC =+3V
1.248
VCC =+5V
1.246
1.244
1.242
1.253
1.252
1.251
1.250
1.249
1.240
-40
-15
10
35
60
85
1.5
4.5
5.5
TSM9117/9118 Reference Voltage
vs Reference Sink Current
1.260
1.260
1.258
1.258
REFERENCE VOLTAGE - V
REFERENCE VOLTAGE - V
TSM9117/9118 Reference Voltage
vs Reference Source Current
1.256
VCC =+1.8V
1.252
1.250
1.248
VCC =+3V, 5V
1.246
3.5
SUPPLY VOLTAGE - Volt
TEMPERATURE - °C
1.254
2.5
1.244
1.242
VCC =+1.8V
1.256
1.254
VCC =+3V, 5V
1.252
1.250
1.248
1.246
1.244
1.242
1.240
1.240
0
2
4
6
8
SOURCE CURRENT- nA
TSM9117_20DS r1p0
10
0
2
4
6
8
10
SINK CURRENT- nA
Page 7
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
Propagation Delay (tPD-) vs Temperature
28
TSM9117/9119 Propagation Delay (tPD+) vs Temperature
60
26
VCC =+5V
50
24
22
tPD+ - µs
tPD- - µs
18
VCC =+3V
16
VCC =+3V
40
VCC =+5V
20
14
30
VCC =+1.8V
20
12
10
VCC =+1.8V
10
8
6
0
-40
-15
10
35
60
-40
85
TEMPERATURE - °C
60
85
160
160
140
VCC =+1.8V
140
120
100
VCC =+3V
80
VCC =+5V
60
VCC =+1.8V
120
tPD+ - µs
tPD- - µs
35
TSM9117/9119 Propagation Delay (tPD+) vs Capacitive Load
180
180
100
80
60
40
40
20
20
VCC =+5V
VCC =+3V
0
0
0.01
0.1
1
10
100
1000
0.01
0.1
1
10
100
1000
CAPACITIVE LOAD - nF
CAPACITIVE LOAD - nF
TSM9117/9119 Propagation Delay (tPD+)
vs Input Overdrive
Propagation Delay (tPD-) vs Input Overdrive
80
70
70
60
60
VCC =+5V
50
VCC =+3V
tPD+ - µs
VCC =+5V
50
tPD- - µs
10
TEMPERATURE - °C
Propagation Delay (tPD-) vs Capacitive Load
200
40
VCC =+3V
30
40
30
VCC =+1.8V
20
20
10
VCC =+1.8V
10
0
0
0
10
20
30
40
INPUT OVERDRIVE - mV
Page 8
-15
50
0
10
20
30
40
50
INPUT OVERDRIVE - mV
TSM9117_20DS r1p0
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
TSM9118/9120 Propagation Delay (tPD-) vs Pullup Resistance
TSM9118/9120 Propagation Delay (tPD+) vs Pullup Resistance
15
200
14
180
160
VCC =+5V
13
140
tPD+ - µs
tPD- - µs
12
11
10
VCC =+3V
9
VCC =+5V
120
100
VCC =+3V
80
60
8
VCC =+1.8V
40
7
20
VCC =+1.8V
6
10
100
0
1k
10k
10
100
1k
100k
RPULLUP - kΩ
Propagation Delay (tPD-) at VCC = +5V
TSM9117/9119
Propagation Delay (tPD+) at VCC = +5V
OUTPUT
OUTPUT
INPUT
INPUT
RPULLUP - kΩ
Propagation Delay (tPD-) at VCC = +3V
TSM9117/9119
Propagation Delay (tPD+) at VCC = +3V
OUTPUT
OUTPUT
INPUT
20µs/DIV
INPUT
20µs/DIV
20µs/DIV
TSM9117_20DS r1p0
20µs/DIV
Page 9
RTFDS
TSM9117-TSM9120
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = +5V; VEE = 0V; CL = 15pF; VOVERDRIVE = 100mV; TA = +25°C, unless otherwise noted.
TSM9117/9119
Propagation Delay (tPD+) at VCC = +1.8V
OUTPUT
OUTPUT
INPUT
INPUT
Propagation Delay (tPD-) at VCC = +1.8V
TSM9117/9119
10kHz Transient Response at VCC = +1.8V
TSM9117/9119
1kHz Transient Response at VCC = +5V
OUTPUT
OUTPUT
INPUT
20µs/DIV
INPUT
20µs/DIV
20µs/DIV
200µs/DIV
OUTPUT
INPUT
Power-Up/Power-Down Transient Response
0.2s/DIV
Page 10
TSM9117_20DS r1p0
RTFDS
TSM9117-TSM9120
PIN FUNCTIONS
TSM9117/TSM9118
SC70
SO
1
6
2
4
3
3
TSM9119/TSM9120
SC70
SO
1
6
2
4
3
3
NAME
OUT
VEE
IN+
4
2
—
—
REF
5
—
—
7
—
1, 5, 8
5
4
—
7
2
1, 5, 8
VCC
INNC
FUNCTION
Comparator Output
Negative Supply Voltage
Comparator Noninverting Input
1.252V Reference Output and
Comparator Inverting Input
Positive Supply Voltage
Comparator Inverting Input
No Connection. Not internally connected.
BLOCK DIAGRAMS
DESCRIPTION OF OPERATION
Guaranteed to operate from +1.6V supplies, the
TSM9117 and the TSM9118 comparators only draw
600nA supply current, feature a robust input stage
that can tolerate input voltages 200mV beyond the
power supply rails, and include an on-board +1.252V
±1.75% voltage reference. The comparator-only
TSM9119 and the TSM9120 have the same attributes
and only draw a supply current of 350nA. To insure
clean output switching behavior, all four analog
comparators feature 4mV internal hysteresis. The
TSM9117 and the TSM9119’s push-pull output
drivers were designed to minimize supply-current
surges while driving ±5mA loads with rail-to-rail
output swings. The open-drain output stage
TSM9118 and TSM9120 can be connected to supply
voltages above VCC to an absolute maximum of 6V
above VEE. Where wired-OR logic connections are
TSM9117_20DS r1p0
needed, their open-drain output stages make it easy
to use these analog comparators.
Input Stage Circuitry
The robust design of the analog comparators’ input
stage can accommodate any differential input voltage
from VEE - 0.2V to VCC + 0.2V. Input bias currents are
typically ±0.15nA so long as the applied input voltage
remains between the supply rails. ESD protection
diodes - connected internally to the supply rails protect comparator inputs against overvoltage
conditions. However, if the applied input voltage
exceeds either or both supply rails, an increase in
input current can occur when these ESD protection
diodes start to conduct.
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TSM9117-TSM9120
Output Stage Circuitry
Many conventional analog comparators can draw
orders of magnitude higher supply current when
switching. Because of this behavior, additional
power supply bypass capacitance may be required
to provide additional charge storage during
switching. The design of the TSM9117–TSM9120’s
rail-to-rail output stage implements a technique that
virtually eliminates supply-current surges when
output transitions occur. As shown on Page 5 of the
Typical Operating Characteristics, the supply-current
change as a function of output transition frequency
exhibited by this analog comparator family is very
small. Material benefits of this attribute to batterypower applications is the increase in operating time
and in reducing the size of power-supply filter
capacitors.
voltage reference is typically 200kΩ, preventing the
reference from driving large loads. The reference is
Figure 1: TSM9117 & TSM9118 Internal VREF
Output Equivalent Circuit
TSM9117/9118’s Internal +1.252V VREF
The TSM9117 and the TSM9118’s internal +1.252V
voltage reference exhibits a typical temperature
coefficient of 100ppm/°C over the full -40°C to
+85°C temperature range. An equivalent circuit for
the reference section is illustrated in Figure 1. Since
the output impedance of the voltage reference
typically 200kΩ, its output can be bypassed with a
low-leakage capacitor and is stable for any
capacitive load. An external buffer – such as the
TS1001 – can be used to buffer the voltage
reference output for higher output current drive or to
reduce reference output impedance.
APPLICATIONS INFORMATION
Low-Voltage, Low-Power Operation
Designed specifically for low-power applications, the
TSM9117–TSM9120 comparators are an excellent
choice. Under nominal conditions, approximate
operating times for this analog comparator family is
illustrated in Table 1 for a number of battery types
and their charge capacities.
Internal Hysteresis
As a result of circuit noise or unintended parasitic
feedback, many analog comparators often break into
oscillation within their linear region of operation
especially when the applied differential input voltage
approaches 0V (zero volt). Externally-introduced
hysteresis is a well-established technique to
stabilizing analog comparator behavior and requires
external components. As shown in Figure 2, adding
comparator hysteresis creates two trip points: VTHR
(for the rising input voltage) and VTHF (for the falling
input voltage). The hysteresis band (VHB) is defined
as the voltage difference between the two trip points.
When a comparator’s input voltages are equal,
Table 1: Battery Applications using the TSM9117- TSM9120
2000
TSM9117/TSM9118
OPERATING TIME
(hrs)
6
2.5 x 10
TSM9119/TSM9120
OPERATING TIME
(hrs)
6
5 x 10
1.8
750
937,500
1.875 x 10
3.5
2.7
1000
1.25 x 10
6
2.5 x 10
6
2.4
1.8
1000
1.25 x 10
6
2.5 x 10
6
BATTERY TYPE
RECHARGEABLE
VFRESH
(V)
VEND-OF-LIFE (V)
CAPACITY, AA
SIZE (mA-h)
Alkaline (2 Cells)
Nickel-Cadmium
(2 Cells)
Lithium-Ion (1 Cell)
Nickel-MetalHydride (2 Cells)
No
3.0
1.8
Yes
2.4
Yes
Yes
Page 12
6
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TSM9117-TSM9120
hysteresis effectively forces one comparator input to
move quickly past the other input, moving the input
out of the region where oscillation occurs. out of the
region where oscillation occurs. Figure 2 illustrates
the case in which an IN- input is a fixed voltage and
an IN+ is varied. If the input signals were reversed,
the figure would be the same with an inverted
output. To save cost and external pcb area, an
internal 4mV hysteresis circuit was added to the
TSM9117–TSM9120.
1) Setting R2. As the leakage current at the IN
pin is less than 2nA, the current through R2
should be at least 0.2μA to minimize offset
voltage errors caused by the input leakage
current. The current through R2 at the trip
point is (VREF - VOUT)/R2.
In solving for R2, there are two formulas –
one each for the two possible output states:
R2 = VREF/IR2
or
R2 = (VCC - VREF)/IR2
From the results of the two formulae, the
smaller of the two resulting resistor values is
chosen. For example, when using the
TSM9117 (VREF = 1.252V) at a VCC = 3.3V
and if IR2 = 0.2μA is chosen, then the
formulae above produce two resistor values:
6.26MΩ and 10.24MΩ - the 6.2MΩ standard
value for R2 is selected.
Figure 2: TSM9117-TSM9120 Threshold Hysteresis
Band
Adding Hysteresis to the TSM9117/TSM9119
The TSM9117/TSM9119 exhibit an internal
hysteresis band (VHYSB) of 4mV. Additional
hysteresis can be generated with three external
resistors using positive feedback as shown in Figure
3. Unfortunately, this method also reduces the
2) Next, the desired hysteresis band (VHYSB) is
set. In this example, VHYSB is set to 100mV.
3) Resistor R1 is calculated according to the
following equation:
R1 = R2 x (VHYSB/VCC)
and substituting the values selected in 1)
and 2) above yields:
R1 = 6.2MΩ x (100mV/3.3V) = 187.88kΩ.
The 187kΩ standard value for R1 is chosen.
4) The trip point for VIN rising (VTHR) is chosen
such that VTHR > VREF x (R1 + R2)/R2 (VTHF
is the trip point for VIN falling). This is the
threshold voltage at which the comparator
switches its output from low to high as VIN
rises above the trip point. In this example,
VTHR is set to 3V.
5) With the VTHR from Step 4 above, resistor R3
is then computed as follows:
`
Figure 3: Using Three Resistors Introduces Additional
Hysteresis in the TSM9117 & TSM9119.
hysteresis response time. Use the
procedure to calculate resistor values.
TSM9117_20DS r1p0
following
R3 = 1/[VTHR/(VREF x R1) - (1/R1) - (1/R2)]
R3 = 1/[3V/(1.252V x 187kΩ)
- (1/187kΩ) - (1/6.2MΩ)] = 136.9kΩ
Page 13
RTFDS
TSM9117-TSM9120
where the smaller of the two resulting
resistor values is the best starting value.
In this example, a 137kΩ, 1% standard
value resistor is selected for R3.
6)
2) As before, the desired hysteresis band
(VHYSB) is set to 100mV.
The last step is to verify the trip voltages
and hysteresis band using the standard
resistance values:
3) Next, resistor R1 is then computed
according to the following equation:
For VIN rising:
VTHR = VREF x R1 [(1/R1) + (1/R2) + (1/R3)]
= 3V
and, for VIN falling:
VTHF = VTHR - (R1 x VCC/R2) = 2.9V
and Hysteresis Band = VTHR – VTHF = 100mV
Adding Hysteresis to the TSM9118/TSM9120
The TSM9118/TSM9120 have a 4mV internal
hysteresis band. Both products have open-drain
outputs and require an external pullup resistor to VCC
as shown in Figure 4. Additional hysteresis can be
R1 = (R2 + R4) x (VHYSB/VCC)
4) The trip point for VIN rising (VTHR) is chosen
(again, remember that VTHF is the trip point
for VIN falling). This is the threshold voltage
at which the comparator switches its output
from low to high as VIN rises above the trip
point.
5) With the VTHR from Step 4 above, resistor R3
is computed as follows:
R3 = 1/[VTHR/(VREF x R1) - (1/R1) - (1/R2)]
6) As before, the last step is to verify the trip
voltages and hysteresis band with the
standard resistor values used in the circuit:
For VIN rising:
VTHR = VREF x R1 x (1/R1+1/R2+1/R3)
and, for VIN falling:
VTHF = VREF x R1 x [1/R1+1/R3+1/(R2+R4)]
-[R1/(R2+R4)] x VCC
and Hysteresis Band is given by VTHR - VTHF
Figure 4: Using Four Resistors Introduces Additional
Hysteresis in the TSM9118 & TSM9120.
generated using positive feedback; however,
formulae differ slightly from those of
TSM9117/TSM9119. The procedure to calculate
resistor values for the TSM9118/TSM9120 is
follows:
1) As in the previous section, resistor R2 is
chosen according to the formulae:
the
the
the
as
PC Board Layout and Power-Supply Bypassing
While power-supply bypass capacitors are not
typically required, it is good engineering practice to
use 0.1µF bypass capacitors close to the device’s
power supply pins when the power supply
impedance is high, the power supply leads are long,
or there is excessive noise on the power supply
traces. To reduce stray capacitance, it is also good
engineering practice to make signal trace lengths as
short as possible. Also recommended are a ground
plane and surface mount resistors and capacitors.
R2 = VREF/0.2µA
or
R2 = (VCC - VREF)/0.2μA - R4
Page 14
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TSM9117-TSM9120
A Zero-Crossing Detector
To configure a zero-crossing detector using a
TSM9119 is illustrated in Figure 5. In this example,
the TSM9119’s inverting input is connected to
ground and its noninverting input is connected to a
100mVP-P signal source. The TSM9119’s output
changes state as the signal at the noninverting input
crosses 0V.
A Logic-Level Translator
Logic-level translation between two different voltage
systems is easy using the TSM9120 as shown in
Figure 6. This application circuit converts 5V logic to
Figure 6: A 5V-to-3V Logic Level Translator
Figure 5: A Simple Zero-Crossing Detector
TSM9117_20DS r1p0
3V logic levels. In this case, the TSM9120 is
powered by a +5V system and the external pullup
resistor for the TSM9120’s open-drain output is
connected to a +3V system. This configuration
allows the full 5V logic swing without creating
overvoltage on the 3V logic inputs. For 3V to 5V
logic-level translations, simply interchange the +3V
supply voltage connection on the comparator’s VCC
and the +5V supply voltage to the external pullup
resistor
Page 15
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TSM9117-TSM9120
PACKAGE OUTLINE DRAWING
5-Pin SC70 Package Outline Drawing
(N.B., Drawings are not to scale)
Page 16
TSM9117_20DS r1p0
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TSM9117-TSM9120
PACKAGE OUTLINE DRAWING
8-Pin SOIC Package Outline Drawing
(N.B., Drawings are not to scale)
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Page 17
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