TOUCHSTONE TS3002

TS3002
A 1V/1µA Easy-to-Use Silicon Oscillator/Timer
FEATURES
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DESCRIPTION
Ultra Low Supply Current: 1µA at 25kHz
Supply Voltage Operation: 0.9V to 1.8V
Programmable Frequency Range:
o 5.2kHz ≤ FOUT ≤ 90kHz (BOOST = GND)
o 5.2kHz ≤ FOUT ≤ 290kHz (BOOST = VDD)
FOUT Period Drift: 0.044%/°C
PWMOUT Duty Cycle Range: 12% to 90%
Single Resistor and Capacitor Set Output
Frequency
Output Driver Resistance: 160Ω
The TS3002 is the industry’s first and only singlesupply CMOS oscillator fully specified to operate at
1V while consuming a 1µA supply current at an
output frequency of 25kHz. This oscillator is compact,
easy-to-use, and versatile. Optimized for ultra-long
life, battery-powered applications, the TS3002 is
Touchstone’s first oscillator in the “NanoWatt
Analog™” high-performance analog integrated
circuits portfolio. The TS3002 can operate from
single-supply voltages from 0.9V to 1.8V.
Requiring only a resistor and a capacitor to set the
output frequency, the TS3002 represents a 66%
reduction in pcb area and a factor-of-10 reduction in
power consumption over other CMOS-based
integrated circuit oscillators. When compared against
industry-standard 555-timer-based products, the
TS3002 offers up to 93% reduction in pcb area and
four orders of magnitude lower power consumption.
APPLICATIONS
Portable and Battery-Powered Equipment
Low-Parts-Count Nanopower Oscillator
Compact Nanopower Replacement for Crystal and
Ceramic Oscillators
Nanopower Pulse-width Modulation Control
Nanopower Pulse-position Modulation Control
Nanopower Clock Generation
Nanopower Sequential Timing
The TS3002 is fully specified over the -40°C to +85°C
temperature range and is available in a low-profile, 8pin 2x2mm TDFN package with an exposed backside paddle.
TYPICAL APPLICATION CIRCUIT
Supply Current Distribution
Percent of Units - %
35%
30%
25%
20%
15%
10%
5%
0%
0.97
0.99
1.01
1.03
Supply Current - µA
The Touchstone Semiconductor logo is a registered
trademark of Touchstone Semiconductor, Incorporated.
Page 1
© 2012 Touchstone Semiconductor, Inc. All rights reserved.
TS3002
ABSOLUTE MAXIMUM RATINGS
VDD to GND.................................................................. -0.3V to +2V
VCNTRL to GND.............................................................. -0.3V to +2V
RSET to GND .............................................................. -0.3V to +2V
CSET to GND .............................................................. -0.3V to +2V
FOUT, PWMOUT to GND............................................ -0.3V to +2V
Short Circuit Duration FOUT, PWMOUT to GND or VDD
................................................................................ Continuous
Continuous Power Dissipation (TA = +70°C)
8-Pin TDFN (Derate at 23.8mW/°C above +70°C) ....... 1951mW
Operating Temperature Range ................................ -40°C to +85°C
Storage Temperature Range ................................. -65°C to +150°C
Lead Temperature (Soldering, 10s) ..................................... +300°C
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
MARKING
TS3002ITD822TP
Tape
& Reel
-----
Tape
& Reel
3000
AAH
TS3002ITD822T
Lead-free Program: Touchstone Semiconductor supplies only lead-free packaging.
Consult Touchstone Semiconductor for products specified with wider operating temperature ranges.
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TS3002
ELECTRICAL CHARACTERISTICS
VDD = 1V, VCNTRL = VDD, VBOOST = 0V, RSET = 4.32MΩ, CSET = 7.9pF, RLOAD(FOUT) = Open Circuit, CLOAD(FOUT) = 0pF, CLOAD(PWM) = 0pF unless
otherwise noted. Values are at TA = 25°C unless otherwise noted. See Note 1.
PARAMETER
Supply Voltage
SYMBOL
VDD
CONDITIONS
MIN
0.9
TYP
1
1
-40°C ≤ TA ≤ 85°C
2.1
VCNTRL = 0.15 x VDD
Supply Current
FOUT Period
-40°C ≤ TA ≤ 85°C
IDD
2.16
VBOOST = VDD
-40°C ≤ TA ≤ 85°C
VBOOST = VDD, VCNTRL = 0.15 x VDD
-40°C ≤ TA ≤ 85°C
-40°C ≤ TA ≤ 85°C
tFOUT
VBOOST = VDD
FOUT Period Line
Regulation
FOUT Period
Temperature Coefficient
PWMOUT Duty Cycle
ΔtFOUT/V
ΔtFOUT/ΔT
DC(PWMOUT)
3.6
1V ≤ VDD ≤ 1.8V
-40°C ≤ TA ≤ 85°C
37
34.7
36
33
40.6
39.5
MAX
1.8
1.5
2.8
3.7
5.4
3.2
4.8
5.3
7.3
44
45.6
43
48
UNITS
V
µA
µs
1.3
VBOOST = VDD
VBOOST = VDD
VCNTRL = 0.03 x VDD
VCNTRL = 0.15 x VDD
VCNTRL = 0.27 x VDD
VCNTRL = 0.03 x VDD
VCNTRL = 0.15 x VDD
VCNTRL = 0.27 x VDD
%/V
-1.6
VBOOST = VDD
4.5
44
83
4.5
47
86
0.044
0.086
8.9
49.3
90.5
8.5
50.4
91.2
%/°C
13
54
97
12.5
54
96
%
FOUT, PWMOUT
Rise Time
FOUT, PWMOUT
Fall Time
FOUT Jitter
tRISE
See Note 2, CL = 15pF
8.6
ns
tFALL
See Note 2, CL = 15pF
7.9
ns
See Note 3
0.08
%
RSET Pin Voltage
V(RSET)
0.3
25
V
45
80
nA
131
77
77
10
mV
mV
mV
mV
nA
CNTRL Output Current
ICNTRL
PWMOUT Enable
PWMOUT Disable
BOOST Enable
BOOST Disable
BOOST Input Current
High Level Output
Voltage, FOUT and
PWMOUT
Low-level Output
Voltage, FOUT and
PWMOUT
VPWM_EN
VPWM_DIS
VIH
VIL
IBOOST
(VDD - VCNTRL ), 0.9V < VDD < 1.8V
(VDD - VCNTRL ), 0.9V < VDD < 1.8V
(VDD – VBOOST ), 0.9V < VDD < 1.8V
0.9V < VDD < 1.8V
VDD - VOH
IOH = 1mA
160
mV
VOL
IOL = 1mA
140
mV
-40°C ≤ TA ≤ 85°C
375
Note 1: All devices are 100% production tested at TA = +25°C and are guaranteed by characterization for TA = TMIN to TMAX, as specified.
Note 2: Output rise and fall times are measured between the 10% and 90% of the V DD power-supply voltage levels. The specification is based
on lab bench characterization and is not tested in production.
Note 3: Timing jitter is the ratio of the peak-to-peak variation of the period to the mean of the period. The specification is based on lab bench
characterization and is not tested in production.
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TS3002
TYPICAL PERFORMANCE CHARACTERISTICS
VDD = 1V, VCNTRL = VDD, VBOOST = 0V, RSET = 4.32MΩ, CSET = 7.9pF, RLOAD(FOUT) = Open Circuit, CLOAD(FOUT) = 5pF, unless otherwise noted.
Values are at TA = 25°C unless otherwise noted.
Supply Current vs FOUT Period
Supply Current vs FOUT Period
2.5
8.5
BOOST = VDD
SUPPLY CURRENT - µA
SUPPLY CURRENT - µA
BOOST = GND
2
1.5
1
0.5
7.1
5.7
4.3
2.9
1.5
0
40
80
120
160
200
0
160
Supply Current vs CLOAD(FOUT)
Supply Current vs CLOAD(FOUT)
200
3.2
BOOST = VDD
SUPPLY CURRENT - µA
1.8
1.6
1.4
1.2
1
3
2.8
2.6
2.4
2.2
0
10
20
30
2
40
0
10
CLOAD- pF
41.2
120
PERIOD - µs
BOOST = GND
SUPPLY CURRENT - µA
80
PERIOD - µs
2
0.8
40
20
30
40
CLOAD- pF
FOUT Period vs Supply Voltage
FOUT Period vs Supply Voltage
40
BOOST = VDD
BOOST = GND
39.8
PERIOD - µs
PERIOD - µs
41
40.8
40.6
39.6
39.4
39.2
39
40.4
38.8
0.9 1.05
1.2
1.35
1.5
1.65
SUPPLY VOLTAGE - Volt
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1.8
0.9 1.05
1.2
1.35
1.5
1.65
1.8
SUPPLY VOLTAGE - Volt
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TS3002
TYPICAL PERFORMANCE CHARACTERISTICS
VDD = 1V, VCNTRL = VDD, VBOOST = 0V, RSET = 4.32MΩ, CSET = 7.9pF, RLOAD(FOUT) = Open Circuit, CLOAD(FOUT) = 5pF, unless otherwise noted.
Values are at TA = 25°C unless otherwise noted.
FOUT Period vs Temperature
FOUT Period vs Temperature
43
41.5
BOOST = VDD
41
42
40.5
PERIOD - µs
PERIOD - µs
BOOST = GND
42.5
41.5
41
40.5
40
40
39.5
39
38.5
39.5
-40
38
-15
10
35
60
85
-40
10
35
60
TEMPERATURE - ºC
TEMPERATURE - ºC
Supply Current vs Temperature
Supply Current vs Temperature
1.5
85
3.2
BOOST = GND
BOOST = VDD
SUPPLY CURRENT - µA
SUPPLY CURRENT - µA
-15
1.36
1.22
1.08
0.94
0.8
2.88
2.56
2.24
1.92
1.6
-40
-15
10
35
60
85
-40
-15
TEMPERATURE - ºC
35
60
85
TEMPERATURE - ºC
Start-up Time vs Supply Voltage
1.8
10
Period vs RSET
200
1.66
PERIOD - µs
START-UP TIME - ms
BOOST = GND
160
1.52
1.38
120
80
40
1.24
1.1
0
0.9
1.2
1.5
SUPPLY VOLTAGE - Volt
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1.8
0
4
8
12
16
20
RSET - MΩ
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TS3002
TYPICAL PERFORMANCE CHARACTERISTICS
VDD = 1V, VCNTRL = VDD, VBOOST = 0V, RSET = 4.32MΩ, CSET = 7.9pF, RLOAD(FOUT) = Open Circuit, CLOAD(FOUT) = 5pF, unless otherwise noted.
Values are at TA = 25°C unless otherwise noted.
Period vs RSET
Period vs CSET
200
100
BOOST = VDD
BOOST = GND
160
PERIOD - µs
PERIOD - µs
80
120
80
60
40
40
0
20
0
4
8
12
16
20
4
RSET - MΩ
8
12
16
20
CSET - pF
FOUT and PWMOUT Transient Response
VDD = 1V, VCNTRL = 0.035 x VDD, BOOST = VDD, CLOAD = 22pF
Period vs CSET
100
BOOST = VDD
FOUT
60
PWMOUT
PERIOD - µs
80
40
20
0
0
4
8
12
16
20
5µs/DIV
CSET - pF
5µs/DIV
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FOUT Transient Response
VDD = 1.5V, BOOST = VDD, CLOAD = 47pF
FOUT
FOUT
FOUT Transient Response
VDD = 1V, BOOST = VDD, CLOAD = 47pF
5µs/DIV
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TS3002
PIN FUNCTIONS
PIN
NAME
1
FOUT
2
BOOST
3
PWMOUT
4
CNTRL
5
CSET
6
GND
7
RSET
8
VDD
EP
-----
TS3002DS r1p0
FUNCTION
Fixed Frequency Output. A push-pull output stage with an output
resistance of 160Ω, the FOUT pin swings from GND to VDD. For
lowest power operation, capacitive loads should be minimized
and resistive loads should be maximized.
BOOST Input. A digital switch input, BOOST controls the
propagation delay of the primary timing comparator in the
TS3002’s master oscillator subcircuit. Connecting the BOOST pin
to GND sets the maximum programmable oscillator frequency to
~90kHz.Connecting the BOOST pin to VDD reduces the
comparator’s propagation delay and increases the maximum
programmable master oscillator’s frequency to 290kHz.
Pulse-width Modulated Output. A push-pull output stage with an
output resistance of 160Ω, the PWMOUT pin is wired anti-phase
with respect to FOUT and swings from GND to VDD. For lowest
power operation, capacitive loads should be minimized and
resistive loads should be maximized.
PWMOUT Enable and Duty Cycle Control Input. An analog input
pin, the VCNTRL pin voltage enables the TS3002’s PWM engine
and controls the duty cycle at PWMOUT from 12%
(VCNTRL = 0.03 x VDD) to 90% (VCNTRL = 0.27 x VDD). Enabling the
PWM engine increases the TS3002’s nominal operating supply
current. To disable the TS3002’s PWM engine, CNTRL shall be
connected to VDD.
FOUT Programming Capacitor Input. A 7.9pF capacitor
connected from this pin to GND in junction with a 4.32MΩ resistor
at the RSET pin sets the TS3002’s internal oscillator’s output
period to ~40µs (25kHz). The maximum capacitance value is
22pF.
Ground – Connect this pin to the system’s analog ground plane.
FOUT Programming Resistor Input. A 4.32MΩ resistor connected
from this pin to GND sets the TS3002’s internal oscillator’s output
period to 40μs (25kHz). For optimal performance, the
composition of the RSET resistor shall be consistent with
tolerances of 1% or lower. The RSET pin voltage is 0.3V at a 1V
supply.
Power Supply Voltage Input. While the TS3002 is fully specified
at 1V, the supply voltage range is 0.9V ≤ VDD ≤ 1.8V. It is always
considered good engineering practice to bypass the V DD pin with
a 0.1μF ceramic decoupling capacitor in close proximity to the
TS3002.
Exposed paddle is electrically connected to GND.
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TS3002
BLOCK DIAGRAM
THEORY OF OPERATION
The TS3002 is a user-programmable oscillator where
the period of the square wave at its FOUT terminal is
generated by an external resistor and capacitor pair.
The output frequency is given by:
FOUT (kHz) =
1
tFOUT ( s)
1E
k RSET MΩ x CSET (pF)
Table 1: FOUT vs RSET, CSET = 7.9pF
RSET (MΩ)
1
2.49
4.32
6.81
9.76
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FOUT (kHz)
106
43
25
16
11
where the scalar k is approximately 1.19. With an
RSET = 4.32MΩ and a CSET = 7.9pF, the output
frequency is approximately 25kHz with a 50% duty
cycle. As design aids, Tables 1 lists TS3002’s typical
FOUT for various standard values for RSET with CSET
= 7.9pF and Table 2 lists typical FOUT for various
standard values for CSET with RSET = 4.32MΩ.
The TS3002 also provides a separate PWM output
signal at its PWMOUT terminal that is anti-phase with
respect to FOUT. In addition, applying a voltage at
Table 2: FOUT vs CSET, RSET = 4.32MΩ
CSET (pF)
5
7.9
10
15
20
FOUT (kHz)
39
25
19
13
10
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TS3002
the CNTRL both enables the TS3002’s internal PWM
engine as well as adjusting the duty cycle from 12%
to 90%. A dc control voltage equal to 0.03 x VDD
applied to the CNTRL pin enables the PWM engine
to set the duty cycle to 12%. A dc control voltage
equal to 0.27 x VDD increases the duty cycle to 90%
and connecting CNTRL to VDD disables the PWM
engine altogether. Configured for nominal operation
(PWM engine OFF, BOOST pin to GND), the supply
current of the TS3002 is 1µA; enabling the PWM
engine increases the TS3002 operating supply
current as shown in the electrical specification table.
The BOOST pin controls the propagation delay of the
TS3002’s internal comparators. When BOOST is
connected to GND, the TS3002’s maximum
programmable operating frequency is ~90kHz.
Connecting the BOOST pin to VDD reduces the
propagation delay of the internal oscillators, thereby
extending the high end maximum operating
frequency to 290kHz.
APPLICATIONS INFORMATION
Minimizing Power Consumption
To keep the TS3002’s power consumption low,
resistive loads at the FOUT and PWMOUT terminals
increase dc power consumption and therefore should
be as large as possible. Capacitive loads at the
FOUT and PWMOUT terminals increase the
TS3002’s transient power consumption and, as well,
should be as small as possible.
One challenge to minimizing the TS3002’s transient
power consumption is the probe capacitance of
oscilloscopes and frequency counter instruments.
Most instruments exhibit an input capacitance of
15pF or more. Unless buffered, the increase in
transient load current can be as much as 400nA.
To minimize capacitive loading, the technique shown
in Figure 1 can be used. In this circuit, the principle of
series-connected capacitors can be used to reduce
Figure 1: Using an External Capacitor in Series with
Probes Reduces Effective Capacitive Load.
TS3002DS r1p0
the effective capacitive load at the TS3002’s FOUT
and PWMOUT terminals.
To determine the optimal value for CEXT once the
probe capacitance is known by simply solving for
CEXT using the following expression:
CE
T
1
=
1
CLOAD(EFF)
1
CPROBE
For example, if the instrument’s input probe
capacitance is 15pF and the desired effective load
capacitance at either or both FOUT and PWMOUT
terminals is to be ≤5pF, then the value of CEXT should
be ≤7.5pF.
TS3002 Start-up Time
As the TS3002 is powered up, its FOUT terminal
(and PWMOUT terminal, if enabled) is active once
the applied VDD is higher than 0.9 volt. Once the
applied VDD is higher than 0.9 volt, the master
oscillator achieves steady-state operation within
1.2ms.
Current- and Voltage-Controlled Oscillators
The TS3002 can be configured into a CurrentControlled Oscillator as shown in Figure 2. With a
current source sourcing a current of 223nA to 262nA,
FOUT can generate an output signal with a frequency
range of 5.2kHz to 90kHz. In a similar manner, a
Figure 2: Configuring the TS3002 into a
Current-Controlled Oscillator.
Voltage-Controlled Oscillator can be configured as
shown in Figure 3. In this case, a voltage source
sourcing a voltage of 290mV to 341mV can generate
an FOUT output signal frequency range of 5.2kHz to
90kHz as well. It is recommended to use resistor
values with a 1% tolerance.
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RTFDS
TS3002
Using Standard Resistors to Increase FOUT
Resolution
Figure 3: Configuring the TS3002 into a VoltageControlled Oscillator.
Using a Potentiometer to Trim the TS3002’s
Output Frequency
The TS3002 can be configured to provide a 0.1%
resolution on the output frequency as shown in
Figure 5. To do so, R1 can be set to approximately
10% of the value selected for R2. In addition, R2 and
R1 should be chosen with a 0.1% and 1% tolerance,
respectively. Since R2 is 90% of the total resistance,
it has the largest impact on the resolution of the
output frequency. With R1 = 91kΩ and R2 = 910kΩ,
the output frequency is 90kHz and with R1 = 400kΩ
and R2 = 4MΩ, the output frequency is 23kHz.
By using a fixed resistor and a potentiometer, the
output frequency of the TS3002 can be trimmed as
shown in Figure 4. By selecting a fixed resistor R1
with a tolerance of 0.1% and a potentiometer P1 with
a 5% tolerance, the output frequency can be trimmed
to provide a ±2% trimming range. As shown in Figure
5, R1+P1 and C2 set the output frequency to
25.052kHz when P1 = 0Ω and with P1 =200kΩ, the
resulting output frequency is 24.024kHz.
Figure 5: Setting the TS3002’s Output
Frequency to 0.1% Resolution using
Standard Resistors.
Figure 4: Using a Fixed Resistor and a
Potentiometer to Trim the TS3002’s
Output Frequency.
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TS3002
PACKAGE OUTLINE DRAWING
8-Pin TDFN22 Package Outline Drawing
(N.B., Drawings are not to scale)
BOTTOM VIEW
SIDE VIEW
NOTE:
All dimensions are in mm.
Compliant with JEDEC MO-229
Information furnished by Touchstone Semiconductor is believed to be accurate and reliable. However, Touchstone Semiconductor does not
assume any responsibility for its use nor for any infringements of patents or other rights of third parties that may result from its use, and all
information provided by Touchstone Semiconductor and its suppliers is provided on an AS IS basis, WITHOUT WARRANTY OF ANY KIND.
Touchstone Semiconductor reserves the right to change product specifications and product descriptions at any time without any advance
notice. No license is granted by implication or otherwise under any patent or patent rights of Touchstone Semiconductor. Touchstone
Semiconductor assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using Touchstone Semiconductor components. To minimize the risk associated with customer products and applications,
customers should provide adequate design and operating safeguards. Trademarks and registered trademarks are the property of their
respective owners.
Touchstone Semiconductor, Inc.
630 Alder Drive, Milpitas, CA 95035
+1 (408) 215 - 1220 ▪ www.touchstonesemi.com
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