XC6121/XC6122
XC6123/XC6124
Series
■GENERAL
DESCRIPTION
ETR0209-009
Voltage Detector with Watchdog Function and ON/OFF Control (V
DF
=1.6V~5.0V)
The XC6121/XC6122/XC6123/XC6124 series are groups of high-precision, low current consumption voltage detectors with
watchdog functions incorporating CMOS process technology. The series consist of a reference voltage source, delay circuit,
comparator, and output driver. With the built-in delay circuit, the XC6121/XC6122/XC6123/XC6124 series’ ICs do not require
any external components to output signals with release delay time. The output type is V
DFL
low when detected. With the
XC6121/XC6122/XC6123/XC6124 series’ ICs, the EN/ENB pin can control ON and OFF of the watchdog functions. By setting
the EN/ENB pin to low or high level, the watchdog function can be OFF while the voltage detector remains operation. Since
the EN/ENB pin of the XC6122 and XC6124 series is internally pulled up to the V
IN
pin or pulled down to the V
SS
pin, the ICs
can be used with the EN/ENB pin left open, when the watchdog functions is used. The detect voltages are internally fixed
1.6V ~ 5.0V in increments of 100mV, using laser trimming technology. Six watchdog timeout period settings are available in a
range from 50ms to 1.6s. Five release delay time settings are available in a range from 3.13ms to 400ms.
■APPLICATIONS
●Microprocessor
watchdog monitoring
and reset circuits
●Memory
battery backup circuits
●System
power-on reset circuits
●Power
failure detection
■FEATURES
Detect Voltage Range
Hysteresis Width
Operating Voltage Range
Detect Voltage Temperature
Characteristics
: +100ppm/
O
C (TYP.)
Output Configuration
: N-channel open drain
Watchdog Pin
: Watchdog input
If watchdog input maintains ‘H’
or ‘L’ within the watchdog
timeout period, a reset signal is
output from the RESETB pin.
EN/ENB Pin
: When the EN/ENB pin voltage is
set to low or high level, the
watchdog function is forced off.
Release Delay Time
: 400ms, 200ms, 100ms, 50ms,
3.13ms (TYP.)
Watchdog Timeout Period
: 1.6s, 800ms, 400ms, 200ms,
100ms, 50ms (TYP.)
Package
: SOT-25, USP-6C
: 1.6V ~ 5.0V, +2%
(100mV increments)
: V
DFL
x 5% (TYP.)
: 1.0V ~ 6.0V
■TYPICAL
APPLICATION CIRCUIT
■TYPICAL
PERFORMANCE
CHARACTERISTICS
●Supply
Current vs. Input Voltage
ＸＣ６１２１½ＸＣ６１２４(V
DF
=２.７Ｖ）
14.0
Ta=85℃
(μA)
Supply Current: I
SS
12.0
10.0
8.0
6.0
4.0
2.0
0
0
1
2
3
4
Input Voltage: V
IN
(V)
5
6
Ta=25℃
Ta=-40℃
1/23
XC6121/XC6122/XC6123/XC6124
Series
■PIN
CONFIGURATION
SOT-25
(TOP VIEW)
USP-6C
(BOTTOM VIEW)
* The dissipation pad for the USP-6C package should be
solder-plated in recommended mount pattern and metal
masking so as to enhance mounting strength and heat
release. If the pad needs to be connected to other pins, it
should be connected to the V
SS
(No. 5) pin.
■PIN
ASSIGNMENT
PIN NUMBER
SOT-25
1
2
3
4
5
-
USP-6C
4
5
2
1
6
3
PIN NAME
R
ESETB
V
SS
EN/ENB
WD
V
IN
NC
FUNCTION
Reset Output
Ground
Watchdog ON/OFF Control
Watchdog
Power Input
No Connection
2/23
XC6121/XC6122/XC6123/XC6124
Series
■PRODUCT
CLASSIFICATION
●Selection
Guide
RESET OUTPUT
SERIES
XC6121
XC6122
XC6123
XC6124
V
DFL
(RESETB)
N-channel open drain
N-channel open drain
N-channel open drain
N-channel open drain
V
DFH
(RESET)
-
-
-
-
Available:
V
DFL
x 5% (TYP.)
HYSTERESIS
EN/ENB PIN FUNCTION
(EN/ENB INPUT LOGIC*,
PULL-UP OR DOWN RESISTOR)
EN with No Pull-Up Resistor
EN with Pull-Up Resistor
ENB with No Pull-Down Resistor
ENB with Pull-Down Resistor
* EN input logic: The watchdog function turns on when the EN pin becomes high level.
* ENB input logic: The watchdog function turns on when the ENB pin becomes low level.
●Ordering
Information
XC6121①②③④⑤⑥: N-channel Open Drain Output (RESETB), EN Pin: No Pull-Up Resistor
XC6122①②③④⑤⑥: N-channel Open Drain Output (RESETB), EN Pin: Pull-Up Resistor
XC6123①②③④⑤⑥: N-channel Open Drain Output (RESETB), ENB Pin: No Pull-Down Resistor
XC6124①②③④⑤⑥: N-channel Open Drain Output (RESETB), ENB Pin: Pull-Down Resistor
DESIGNATOR
DESCRIPTION
SYMBOL
A
C
①
Release Delay Time
D
E
F
2
3
②
Watchdog Timeout Period
4
5
7
6
③④
⑥
⑦
Detect Voltage
Packages
Device Orientation
16 ~ 50
M
E
R
L
: 3.13ms (TYP.)
: 50ms (TYP.)
: 100ms (TYP.)
: 200ms (TYP.)
: 400ms (TYP.)
: 50ms (TYP.)
: 100ms (TYP.)
: 200ms (TYP.)
: 400ms (TYP.)
: 800ms (TYP.)
: 1.6s (TYP.)
: Detect voltage
ex.) 4.5V:
③⇒4, ④⇒5
: SOT-25
: USP-6C
: Embossed tape, standard feed
: Embossed tape, reverse feed
DESCRIPTION
* Please set the release delay time shorter than or equal to the watchdog timeout period.
ex.) XC6121D327MR or XC6121D627MR
3/23
XC6121/XC6122/XC6123/XC6124
Series
■BLOCK
DIAGRAMS
●XC6121
Series
N-ch Open Drain Output
●XC6122
Series
N-ch Open Drain Output
4/23
XC6121/XC6122/XC6123/XC6124
Series
■BLOCK
DIAGRAMS (Continued)
●XC6123
Series
N-ch Open Drain Output
●XC6124
Series
N-ch Open Drain Output
5/23
