TS3809/3810 Series Microprocessor Reset Circuit

TS3809/3810 Series
Taiwan Semiconductor
Microprocessor Reset Circuit
GENERAL DESCRIPTION
FEATURES
The TS3809/3810 series are used for microprocessor
●
High Accurate ±2%
(µP) supervisory circuits to monitor the power supplies
●
Precision monitoring of +3V, +3.3V, and +5V
external
●
Fully specified over temperature
components and adjustments when used with +5V,
●
Available in three output configurations
+3.3V, +3.0V, +2.5V powered circuits.
●
Push-Pull RESET low output (TS3809)
These circuits perform a single function: they assert a
●
Push-Pull (RESET) high output (TS3810)
reset signal whenever the VCC supply voltage declines
●
200ms typ. Power-on reset pulse width
below a preset threshold, keeping it asserted for at least
●
25µs supply current
200ms after VCC has risen above the reset threshold.
●
Guaranteed reset valid to VCC=+1V
Reset thresholds suitable for operation with a variety of
●
Power supply transient immunity
supply voltages are available. TS3809/3810 series have
APPLICATION
in µP and digital systems. They provide excellent circuit
reliability
and
low
cost
by
eliminating
Power supply voltage
push pull outputs. TS3809 series has an active low
RESET output, while the TS3810 has an active high
RESET output The reset comparator is designed to
●
Battery-operated systems and controllers
●
Intelligent instruments
●
Critical µP and µC power monitoring
ignore fast transients on VCC, and the outputs are
●
Portable / Battery powered equipment
guaranteed to be in the correct logic state for VCC down
●
Automotive
to 1.0V. Low supply current makes TS3809/3810 series
ideal for use in portable equipment.
SOT-23
Pin Definition
TS3809
TS3810
1. GND
1. GND
2. RESET
2. (RESET)
3. VCC
3. VCC
TYPICAL APPLICATIN CIRCUIT
Document Number: DS_P0000206
1
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
LIMIT
UNIT
VCC
GND - 0.3 to GND +6.5
V
VRESET
GND - 0.3 to VCC +0.3
V
Input Current, VCC
ICC
20
mA
Output Current, RESET, (RESET)
IO
5
mA
Power Dissipation
PD
(TJ-TA)/RθJA
mW
TJ.OPR
-40 ~ +125
o
TSTG
-65 ~ +150
o
TLEAD
10
s
SYMBOL
MAXIMUM
UNIT
RθJC
110
ºC/W
RθJA
250
ºC/W
Terminal Voltage (with respect to GND)
RESET & (RESET) push-pull
Operating Junction Temperature Range
Storage Temperature Range
o
Lead Soldering Temperature (260 C)
C
C
THERMAL PERFORMANCE
PARAMETER
Thermal Resistance from Junction to Case
Thermal Resistance from Junction to Ambient
(Note 1)
ELECTRICAL CHARACTERISTICS (VCC = 5V, TA = 25°C unless otherwise noted)
PARAMETER
CONDITIONS
o
o
SYMBOL
MIN
TYP
MAX
UNIT
Input Supply Voltage
TA=-40 C~+85 C
VCC
1.0
--
6
V
Supply Current
VCC=VTH + 1V
ICC
--
25
35
µA
TS3809/3810CXA
4.54
4.63
4.71
TS3809/3810CXB
4.29
4.38
4.46
TS3809/3810CXC
3.92
4.00
4.08
3.02
3.08
3.15
TS3809/3810CXE
2.87
2.93
3.00
TS3809/3810CXF
2.57
2.63
2.69
TS3809/3810CXG
2.20
2.25
2.30
Reset Threshold
Reset Threshold
TS3809/3810CXD
VTH
V
o
TA=0~+85ºC
VTHT
--
50
--
ppm/ C
Set-up Time
VCC = 0 ~ (VTH - 100mV)
TSET
1
--
--
µs
VCC to Reset Delay
VCC = VTH ~ (VTH - 100mV)
TRD
--
20
--
µs
TDELAY
140
200
260
ms
VOL
--
--
0.3
V
VOH
0.8 VCC
--
--
V
VOL
--
--
0.3
V
Temperature Coefficient
Reset Active Timeout
Period
TA=0~+85ºC
1.8V<VCC<VTH(MAX),
RESET Output (TS3809)
ISINK =1.2mA
Voltage Low
1.2V<VCC<1.8V,
ISINK =50µA
RESET Output (TS3809)
VCC > VTH(MAX),
Voltage High
ISOURCE =500µA
(RESET) Output (TS3810)
Voltage Low
VCC > VTH(MAX), ISINK =1.2mA
Document Number: DS_P0000206
2
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
ELECTRICAL CHARACTERISTICS (VCC = 5V, TA = 25°C unless otherwise noted)
PARAMETER
CONDITIONS
(RESET) Output (TS3810)
1.8V<VCC<VTH(MAX),
Voltage High
ISOURCE =500µA
1.2V<VCC<1.8V,
SYMBOL
MIN
TYP
MAX
UNIT
VOH
0.8 VCC
--
--
V
VHVS
--
40
--
mV
ISOURCE =150µA
Hysteresis at VCC
Input Voltage
Note :
1. RθJA is measured the PCB copper area of approximately 1in2 (Multi-layer). Needs to connect to VSS pin.
Document Number: DS_P0000206
3
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
ORDERING INFORMATION
RESET VOLTAGE
PART NO.
PACKAGE
PACKING
4.63V
TS3809CXA RFG
SOT-23
3,000pcs / 7” Reel
4.38V
TS3809CXB RFG
SOT-23
3,000pcs / 7” Reel
4.00V
TS3809CXC RFG
SOT-23
3,000pcs / 7” Reel
3.08V
TS3809CXD RFG
SOT-23
3,000pcs / 7” Reel
2.93V
TS3809CXE RFG
SOT-23
3,000pcs / 7” Reel
2.63V
TS3809CXF RFG
SOT-23
3,000pcs / 7” Reel
2.25V
TS3809CXG RFG
SOT-23
3,000pcs / 7” Reel
4.63V
TS3810CXA RFG
SOT-23
3,000pcs / 7” Reel
4.38V
TS3810CXB RFG
SOT-23
3,000pcs / 7” Reel
4.00V
TS3810CXC RFG
SOT-23
3,000pcs / 7” Reel
3.08V
TS3810CXD RFG
SOT-23
3,000pcs / 7” Reel
2.93V
TS3810CXE RFG
SOT-23
3,000pcs / 7” Reel
2.63V
TS3810CXF RFG
SOT-23
3,000pcs / 7” Reel
2.25V
TS3810CXG RFG
SOT-23
3,000pcs / 7” Reel
Note:
1. Compliant to RoHS Directive 2011/65/EU and in accordance to WEEE 2002/96/EC.
2. Halogen-free according to IEC 61249-2-21 definition.
BLOCK DIAGRAM
Document Number: DS_P0000206
4
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
CHARACTERISTICS CURVES
(TC = 25°C unless otherwise noted)
Figure 1. Threshold Voltage vs. Temperature
Figure 2. TDELAY vs. Temperature
Figure 3. Supply Current vs. Temperature
Figure 4. Supply Current vs. Threshold Voltage
Figure 5. Power-Down TDELAY vs. Temperature
Figure 6. Output Voltage vs. Output Current
Document Number: DS_P0000206
5
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
APPLICATION INFORMATION
Negative-Going VCC transients in addition to issuing a reset to the µP during power-up, power-down, and brownout
conditions, the TS3809/3810 are relatively immune to short-duration negative-going VCC transients (glitches).
The TS3809/3810 does not generate a reset pulse. The graph was generated using a negative going pulse applied
to VCC, starting 0.5V above the actual reset threshold and ending below it by the magnitude indicated (reset
comparator overdrive). The graph indicates the maximum pulse width a negative going VCC transient can have
without causing a reset pulse. As the magnitude of the transient increases (goes farther below the reset threshold),
the maximum allowable pulse width decreases. Typically, a VCC transient that goes 100mV below the reset
threshold and lasts 20µS or less will not cause a reset pulse. A 0.1µF bypass capacitor mounted as close as
possible to the VCC pin provides additional transient immunity.
FUNCTION DESCRIPTION
A microprocessor’s reset input starts the µP in a known state. The TS3809/3810 assert reset to prevent codeexecution errors during power-up, power-down, or brownout conditions. They assert a reset signal whenever the
VCC supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after VCC has risen
above the reset threshold. The TS3809/3810 have a push-pull output stage.
ENSURING A VALID RESET OUTPUT DOWN TO VCC=0
RESET is guaranteed to be a logic low for VCC > 1.0V. Once VCC exceeds the reset threshold, an internal timer
keeps RESET low for the reset timeout period; after this interval, RESET goes high. If a brownout condition occurs
(VCC dips below the reset threshold), RESET goes low. Any time VCC goes below the reset threshold, the internal
timer resets to zero, and RESET goes low. The internal timer starts after VCC returns above the reset threshold, and
RESET remains low for the reset timeout period. When VCC falls below 1V, the TS3809/3810 reset output no longer
sinks current - it becomes an open circuit. Therefore, high impedance CMOS logic input connected to reset can
drift to undetermined voltages. This present no problem in most applications since most µP and other circuitry is
inoperative with VCC below 1V.However, in applications where reset must be valid down to 0V, adding a pull down
resistor to reset causes and stray leakage currents to flow to ground, holding reset low (Figure 2.) R1’s value is not
critical; 100K is large enough not to load reset and small enough to pull RESET to ground. For the TS3809/3810 if
reset is required to remain valid for VCC <1V.
BENEFITS OF HIGHLY ACCURATE RESET THRESHOLD
Most µP supervisor ICs has reset threshold voltages between 5% and 10% below the value of nominal supply
voltages. This ensures a reset will not occur within 5% of the nominal supply, but will occur when the supply is 10%
below nominal. When using ICs rated at only the nominal supply ±5%, this leaves a zone of uncertainty where the
supply is between 5% and 10% low, and where the reset many or may not be asserted.
TIMMING DIAGRAM
Document Number: DS_P0000206
6
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
PACKAGE OUTLINE DIMENSIONS (Unit: Millimeters)
SOT-23
SUGGESTED PAD LAYOUT (Unit: Millimeters)
MARKING DIAGRAM
PART NO.
IDENTIFICATION CODE
PART NO.
IDENTIFICATION CODE
TS3809CXA
CA
TS3810CXA
CH
TS3809CXB
CB
TS3810CXB
CI
TS3809CXC
CC
TS3810CXC
CJ
TS3809CXD
CD
TS3810CXD
CK
TS3809CXE
CE
TS3810CXE
CL
TS3809CXF
CF
TS3810CXF
CM
TS3809CXG
CG
TS3810CXG
CN
Document Number: DS_P0000206
7
Version: E15
TS3809/3810 Series
Taiwan Semiconductor
Notice
Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf,
assumes no responsibility or liability for any errors or inaccuracies.
Information contained herein is intended to provide a product description only. No license, express or implied, to
any intellectual property rights is granted by this document. Except as provided in TSC’s terms and conditions of
sale for such products, TSC assumes no liability whatsoever, and disclaims any express or implied warranty,
relating to sale and/or use of TSC products including liability or warranties relating to fitness for a particular purpose,
merchantability, or infringement of any patent, copyright, or other intellectual property right.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications.
Customers using or selling these products for use in such applications do so at their own risk and agree to fully
indemnify TSC for any damages resulting from such improper use or sale.
Document Number: DS_P0000206
8
Version: E15