YOBON YB1921TB-F

YB1921
3-Pin Microprocessor Reset Monitor
Features
Introduction
The YB1921 is a cost-effective system
supervisor Integrated Circuit (IC) designed to monitor
VCC in digital and mixed signal systems and provide a
warning signal when the system power supply is out
of working range, and a reset signal to the host
processor when necessary. No external components
are required.
z
Precision VCC Monitor for 2.8V, 3.0V, 3.3V,
and 5.0V Supplies
z
140msec Guaranteed Minimum RESET
Output Duration
z
RESET Output Guaranteed to VCC=1.0V
z
Low 18μA Supply Current
The reset output is driven active within 20μsec
z
VCC Transient Immunity
of VCC falling through the reset voltage threshold.
Reset is maintained active for a minimum of 140msec
after VCC rises above the reset threshold. The YB1921
has an active-low RESET output. The output of the
YB1921 is guaranteed valid down to VCC=1V.
z
Small SOT-23 Package
z
No External Components
z
Wide Operating Temperature: 0°C to 85°C
The YB1921 is optimized to reject fast transient
glitches on the VCC line. Low supply current of 18μA
(VCC=3.3V) makes these devices suitable for battery
powered applications.
Applications
z
Computers
z
Embedded systems
z
Battery powered equipment
z
Critical µP power supply monitoring
Application Diagram
YB1921
www.yobon.com.tw
1
YB1921
3-Pin Microprocessor Reset Monitor
Absolute Maximum Ratings (1)
Parameter
Value
Symbol
Unit
Value
Input Voltage
VCC
5.5
V
RESET
-0.3 to (Vcc+0.3)
V
—
20
mA
Output Current
IOUT
20
mA
Power Dissipation
PD
Internally Limited (3)
—
Output Short Circuit Duration
—
Infinite
—
Thermal Resistance, Junction-to-Ambient
ΘJA
230
°C/W
Operating Temperature Range
TA
0~85
°C
Lead Temperature (Soldering, 10 sec.)
—
260
°C
Junction Temperature
TJ
0 to+125
°C
Storage Temperature
TS
-60 to+150
°C
Output Voltage
Input Current
Recommended Operating Conditions (2)
Parameter
Value
Symbol
Unit
Min
Type.
Max
Power Supply Voltage
VCC
2.0
—
5.5
V
Junction Temperature
TJ
0
—
+125
°C
YB1921
www.yobon.com.tw
2
YB1921
3-Pin Microprocessor Reset Monitor
Electrical Characteristics
Vcc=5V for L/M/J; 3.3V for T/S; 3.0V for R, TA = 25°C, unless otherwise specified.
Parameter
Symbol
Condition
Min
Typ
Max
Unit
Input Voltage
VCC
—
2.0
—
5.5
V
Supply Current
ICC
—
—
18
25
μA
4.54
4.63
4.72
4.29
4.38
4.47
VTH
YB1921L-4.63V
YB1921M-4.38V
YB1921J-4.00V
YB1921T-3.08V
YB1921S-2.93V
YB1921R-2.63V
3.92
4.00
4.08
3.02
3.08
3.14
2.87
2.93
2.99
2.58
2.63
2.68
—
—
—
30
—
ppm/°C
—
—
—
20
—
μsec
Reset Active Timeout Period
—
—
—
240
—
msec
RESET Output Voltage Low
VOL
ISINK = 3mA
—
—
0.4
V
RESET Output Voltage High
VOH
ISOURCE = 800μA
0.8VCC
—
—
V
Reset Threshold
Reset Threshold Temperature
Coefficient (4)
VCC to Reset Delay VCC = VTH to
(VTH – 100mV)
V
Note 1: Exceeding the absolute maximum rating may damage the device.
Note 2: The device is not guaranteed to function outside its operating rating.
Note 3: The maximum allowable power dissipation at any TA (ambient temperature) is calculated using: PD (MAX) =
(TJ (MAX) – TA)/ΘJA. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the
regulator will go into thermal shutdown. See “Thermal Consideration” section for details
Note 4: RESET threshold temperature coefficient is the worst case voltage change divided by the total temperature
range.
YB1921
www.yobon.com.tw
3
YB1921
3-Pin Microprocessor Reset Monitor
Pin Description
Pin Configuration
VCC
3
S809La
2
1
RESET
Pin No.
Symbol
1
GND
RESET
2
GND
3
Vcc
Description
Ground
RESET output remains low while Vcc is
below the reset voltage threshold and
for 240msec(typ) after Vcc rises above
reset threshold
Supply Voltage (typ.)
Ordering/Marking Information
Package
Reset Vcc
Part Number
Marking
4.63
YB1921LB-F
S809La
•
4.38
YB1921MB-F
S809Ma
•
And underlined 9 is for year 2008
4.00
YB1921JB-F
S809Ja
•
2009, and underlined 8 for 2010. The naming
3.08
YB1921TB-F
S809Ta
•
2.93
YB1921SB-F
S809Sa
•
2.63
YB1921RB-F
S809Ra
•
threshold (V)
Marking Information
Starting with 0, a bar underlined 0 is for
production year 2006, on top of 9 is for year 2007.
The next character is marked on top of 8 for
pattern continues with consecutive characters for
SOT-23
later years.
The last character is the week code. (A-Z: 1-26,
a-z: 27-52)
A dot on top right corner is for lead-free process.
Ordering Information
YB1921
www.yobon.com.tw
4
YB1921
3-Pin Microprocessor Reset Monitor
Dimension
Outline Drawing For SOT-23
C
J
H
B
D
A
E
G
F
K
L
INCHES
SYMBOL
YB1921
MILLIMETERS
MIN
MAX
MIN
MAX
A
0.110
0.120
2.80
3.04
B
0.047
0.055
1.20
1.40
C
0.083
0.104
2.10
2.64
D
0.035
0.040
0.89
1.03
E
0.070
0.080
1.78
2.05
F
0.018
0.024
0.45
0.60
G
0.015
0.020
0.37
0.51
H
0.0005
0.004
0.013
0.10
J
0.034
0.040
0.887
1.02
K
0.003
0.007
0.085
0.18
L
—
0.027
—
0.69
www.yobon.com.tw
5