®
RT9833
Micro-Power Voltage Detectors with Manual Reset
General Description
The RT9833 is a micro-power voltage detector with
deglitched manual reset input supervising the power supply
voltage level for microprocessors (μP) or digital systems.
It provides internally fixed threshold levels with 0.1V per
step ranging from 1V to 5V, which covers most digital
applications. It features low supply current of 3μA. The
RT9833 performs supervisory function by sending out a
reset signal whenever the V
DD
voltage falls below a preset
threshold level. This reset signal will last the whole period
before V
DD
recovering. Once V
DD
recovered upcrossing
the threshold level, the reset signal will be released after
a certain delay time. To pull reset signal low manually,
just pull the manual reset input (MR) below the specified
V
IL
level. The RT9833 is available in
the SC-82
package.
Features
Internally Fixed Threshold 1V to 5V in 0.1V Step
High Accuracy
±
1.5%
Low Supply Current 3μA
μ
No External Components Required
Quick Reset within 20μs
μ
Built-in Recovery Delay : 0ms, 55ms, 220ms, 450ms
Options
800ns Glitch Immunity of Manual Reset Input
Low Functional Supply Voltage 0.9V
N-Channel Open-Drain Output
Small SC-82 Package
RoHS Compliant and Halogen Free
Applications
Computers
Controllers
Intelligent Instruments
Critical
μP
and
μC
Power Monitoring
Portable/Battery-Powered Equipment
Ordering Information
RT9833 -
Package Type
Y : SC-82
Lead Plating System
G : Green (Halogen Free and Pb Free)
Threshold Voltage
12 : 1.2V
13 : 1.3V
:
49 : 4.9V
50 : 5.0V
Reset Active Timeout Period
A = 0ms
(RESET)
B = 55ms
(RESET)
C = 220ms
(RESET)
D = 450ms
(RESET)
E = 0ms
(RESET)
F = 55ms
(RESET)
G = 220ms
(RESET)
H = 450ms
(RESET)
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Note :
Richtek products are :
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
Simplified Application Circuit
VDD
µp
RESET/
RESET
RT9833
VDD
MR
RESET/ GND
RESET
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9833-00 May 2013
www.richtek.com
1
RT9833
Pin Configurations
(TOP VIEW)
VDD
4
MR
3
2
GND
RESET/
RESET
SC-82
Functional Pin Description
Pin No.
1
2
3
4
Pin Name
GND
RESET
RESET
MR
VDD
Ground.
Active Low Open Drain Reset Output.
Active High Open Drain Reset Output.
Manual Reset.
Power.
Pin Function
Function Block Diagram
VDD
MR
RESET/
RESET
VSET
Threshold
Voltage Setting
CMP
Timer
N MOS
GND
POR
Power On Reset
Operation
When VDD is lower than threshold voltage set by VSET
circuit, the RESET output becomes high. If VDD remains
higher than the threshold voltage with a hysteresis voltage,
Timer will be active. After a specific delay time, the RESET
output becomes low. There is an internal pull-high resistor
connected to the MR pin. MR resets the RT9833 only
when it is pulled low. When MR releases and waits for a
delay time, output returns to its normal state related to
VDD. It is an open drain output type of Reset IC.
Timer
The Timer provides four kinds of delay time options
including 0ms, 55ms, 220ms, and 450ms.
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
VSET
The VSET generates a fixed threshold voltage.
CMP
Voltage Comparator which compares the voltage difference
between threshold voltage and VDD.
POR
Power on reset. It will set all digital logic to the right state
when power on.
www.richtek.com
2
DS9833-00 May 2013
RT9833
Absolute Maximum Ratings
(Note 1)
Terminal Voltage (with Respect to GND)
VDD -------------------------------------------------------------------------------------------------------------------
−0.3V
to 6V
All Other Inputs ----------------------------------------------------------------------------------------------------
−0.3V
to (V
DD
+ 0 .3V)
Input Current, I
VDD
------------------------------------------------------------------------------------------------- 20mA
Power Dissipation, P
D
@ T
A
= 25°C
SC-82 ---------------------------------------------------------------------------------------------------------------- 0.29W
Package Thermal Resistance (Note 2)
SC-82,
θ
JA
----------------------------------------------------------------------------------------------------------- 345.6°C/W
Lead Temperature (Soldering, 10sec.) ------------------------------------------------------------------------ 260°C
Storage Temperature Range ------------------------------------------------------------------------------------
−65°C
to 125°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) -------------------------------------------------------------------------------------- 2kV
Recommended Operating Conditions
(Note 4)
Junction Temperature Range ------------------------------------------------------------------------------------
−40°C
to 125°C
Ambient Temperature Range ------------------------------------------------------------------------------------
−40°C
to 85°C
Electrical Characteristics
(V
DD
= 3V, unless otherwise specified)
Parameter
Operating V
DD
(V
OUT
) Range
Supply Current
Reset Threshold
MR Input Threshold
MR Glitch Rejection
Threshold Voltage Accuracy
V
DD
Drop to Reset Delay
RT9833A/E
MR Active
Timeout Period
RT9833B/F
RT9833C/G
RT9833D/H
MR Input Voltage Logic-High
Threshold
Logic-Low
RT9833A/E
Reset Active
Time Out Period
RT9833B/F
RT9833C/G
RT9833D/H
RESET Output Voltage Low
Hysteresis Width
Symbol
V
DD
I
DD
V
TH
V
IL
V
IH
ΔV
TH
t
RD
Test Conditions
V
TH
= 3V, V
DD
= 4.5V, T
A
= 27°C
T
A
= 27°C
T
A
= 27°C, V
TH
> 1.2V
T
A
= 27°C, V
TH
> 1.2V
T
A
= 27°C
Drop = V
TH
−125mV
Min
0.9
--
--
--
0.7V
DD
--
−1.5
--
--
35
143
292
0.75 x
V
DD
--
--
Typ
--
3
1.2 to 5
--
--
800
--
20
0
55
220
450
--
--
0
55
220
450
--
0.01V
TH
Max
6
8
--
0.25V
DD
--
--
1.5
--
--
75
297
608
V
DD
0.25 x
V
DD
--
75
297
608
0.4
--
Unit
V
μA
V
V
ns
%
μs
t
MR
ms
V
MR_H
V
MR_L
V
DD
> V
TH(MAX)
V
DD
> V
TH(MAX)
V
t
RP
V
DD
≥
1.02×V
TH
35
143
292
--
--
ms
V
OL
V
HYS
3 = V
DD
< V
TH
I
SINK
> 3.5mA
V
V
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9833-00 May 2013
www.richtek.com
3
RT9833
Note 1.
Stresses beyond those listed
“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 conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2.
θ
JA
is measured at T
A
= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
Note 3.
Devices are ESD sensitive. Handling precaution is recommended.
Note 4.
The device is not guaranteed to function outside its operating conditions.
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
4
DS9833-00 May 2013
RT9833
Typical Application Circuit
VDD
µp
RESET/
RESET
RT9833
4 VDD
MR
3
100k
Pull Up
1
2 RESET/
GND
RESET
Copyright
©
2013 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9833-00 May 2013
www.richtek.com
5