TA8044AF
2002-02-27
1
TOSHIBA BIPOLAR LINEAR INTEGRATED CIRCUIT SILICON MONOLITHIC
TA8044AF
3.3V / 5V DUAL-VOLTAGE REGULATOR WITH WATCHDOG TIMER
Designed specifically for use in 3.3V microcomputers, this IC
contains two constant-voltage power supplies for 3.3V and 5V
uses and various system reset functions.
This IC's Power Supply Output 1 provides an output voltage of
3.4V and contains an output transistor capable of producing
10mA of output current. With an external boost transistor
connected, this IC can supply a large output current. A 150mA
current limiter is included.
Power Supply Output 2 provides an output voltage of 5.0V which
can be turned on or off from the EN pin. This output uses an
external output transistor. Any desired current limiter value can
be set using an external adjusting resistor.
For a system reset, it has a low-voltage monitor / power-on reset /
watchdog timer at Power Supply Output 2.
FEATURES
l Power Supply Output 1
Output voltage
: 3.4V0.15V
Output current
: 10mA (built-in transistor) / 300 mA (when urrent boost transistor connected)
Current limiter
: 150mA
l Power Supply Output 2
Output voltage
: 5.0V (-0.18V to +0.15V)
Output current
: 600mA (External transistor)
Current limiter
: Variable using external adjusting resistor
l Reset functions
: Low-voltage monitor and power-on watchdog timer
l Low standby current
: 800A (Max)
l Wide operating temperature range : -40C to 125C
l Compact flat package SSOP-16pin : 16-pin SSOP
Weight: 0.14 g (typ.)
TA8044AF
2002-02-27
3
PIN DESCRIPTION
PIN No.
SYMBOL
DESCRIPTION
1 V
IN1
Power supply input pin for V
CC1
. It contains a 150mA (Typ.) current limiter.
2 V
S1
Current limiter pin for V
CC1
. A 120msense resistor is included between pin 1 and this pin.
3 OUT1
Power supply input pin for V
CC1
. When using an external current boost transistor, connect the
base of a PNP transistor to this pin. No external transistor is required when using the IC at a
load current of 10mA or less. In this case, connect the power supplies by shorting pins 1, 2, and
3.
4 V
CC1
Voltage detection / output pin for V
CC1
. When using a current boost transistor, connect the
collector of a PNP transistor to this pin. When used with a load current of 10mA or less, this pin
serves as an output pin for the 3.3V power supply.
5 COMP1
Phase compensating pin for V
CC
1. Connect a phase compensating capacitor between pin 4 and
this pin.
6 EN
On / off control pin for V
CC2
. The 5V output is turned on when EN is high and turned off when
EN is low. A 50k pull-down resistor is included in GND.
7 GND
Grounded
8
RESET
Power-on reset / watchdog timer reset output pin.
Generates a reset signal that is determined by C
T
and R
T
at the TC pin.
If no clock is fed to the CK input, this pin generates a reset pulse intermittently.
This is an NPN transistor collector output, with a 100k pull-up resistor built into V
CC2
.
9 TC
Time setup pin for the reset and watchdog timers. Connect resistor RT to V
CC2
and capacitor
C
T
to GND.
10 CK
Clock input pin for the watchdog timer. If used only as a power-on reset timer, pull up this input
to V
CC2
.
11 V
CC3
This pin contains a 7.5V Zener diode. To use this pin, short it to pin 13. When the V
CC2
voltage
becomes abnormal, the Zener diode suppresses the voltage.
12 COMP2
Phase compensating pin for V
CC2
. Connect a phase compensating capacitor between pin 13
and this pin.
13 V
CC2
Voltage detection pin for the 5V constant-voltage power supply, V
CC2
. It also supplies power to
the reset timer block.
14 OUT2
This pin is used to connect the base of an external PNP transistor. The output voltage is
controlled by an internal op-amp to maintain it stably at 5V. Since the recommended current of
I
OUT
is 5mA, an output current of up to 600mA can be flowed if HFE of the external transistor is
120 or more.
15 V
S2
Detection pin for the V
CC2
current limiter. A voltage drop occurring in the external resistor Rs
between pins 15 and 16 is monitored. The current limiter is actuated when the voltage drop
exceeds 0.3V.
Ex. ) When the current limiter need to be actuated at a load current of 600mA
Rs = 0.3V / 600mA = 0.5
16 V
IN2
Power supply input pin.
An internal 6V constant voltage is connected to this pin for supplying power to the V
CC1 / 2
current limiters, voltage regulating circuit for V
CC1
, reference voltage source, and the EN input
circuit.
TA8044AF
2002-02-27
6
ELECTRICAL CHARACTERISTICS
Vin = 6 to 16V, I
LOAD-1
= 10mA, I
LOAD-2
= 10mA,
Ta = -40~125C unless otherwise specified
CHARACTERISTIC SYMBOL
PIN
TEST
CIR-
CUIT
TEST CONDITION
MIN
TYP.
MAX
UNIT
Ta
=
-40~105C 3.28
3.4
3.52
V
REG
-1 V
CC
-1
Ta
=
-40~125C 3.25
3.4
3.55
Ta
=
-40~105C 4.85
5.0
5.15
Output Voltage
V
REG
-2 V
CC
-2
Ta
=
-40~125C 4.82
5.0
5.15
V
Input Stability
V
LINE
V
CC
-1 / 2
V
IN
= 6~40V
0.1 0.5 %
V
LOAD
-1 V
CC
-1
I
LOAD
= 1~200mA
0.2 1.0
Load Stability
V
LOAD-2
V
CC
-2
I
LOAD
= 1~300mA
0.2 1.0
%
Temperature Coefficient
V
CC
-1 / 2
0.01 %
/
C
Input Current
I
IN
EN
V
IN
=5V
0.1 0.2 mA
V
IH
2
Input Voltage
V
IL
EN
0.8
V
Output Voltage
V
OL
RESET
I
OL
= 2mA
0.3 V
Output Leakage Current
I
LEAK
RESET
V
IN
= V
CC2
5 A
Input Current
I
IN
TC
V
IN
= 0~3.5V
-3
3 A
V
IH
4
Threshold Voltage
V
IL
TC
2
V
Input Current
I
IN
CK
V
IN
= 5V
0.18 0.35 mA
V
IH
2
Input Voltage
V
IL
CK
0.5
V
Current Limiter
I
LIMIT
V
CC
-1
150 mA
Current Limiter Detection
VLIMIT
V
CC
-2
0.3 V
Standby Current
I
ST
*1
V
IN
= 14V , EN = " L "
400 800 A
Current Consumption
I
CC
*1
V
IN
= 14V , EN = " H "
3 5 mA
V
TH1
3.0
3.15
3.3
V
TH1
V
CC
-1
V
CC
-1-V
TH1
0.2
0.25
0.3
V
TH2
4.5
4.7
4.87
Reset Detection Voltage
V
TH2
V
CC
-2
V
CC
-2-V
TH2
0.25 0.30 0.35
V
Power-on Reset
T
POR
RESET
1.3
C
T
R
T
1.6
C
T
R
T
1.9
C
T
R
T
Watchdog Timer
T
WD
RESET
0.9
C
T
R
T
1.1
C
T
R
T
1.3
C
T
R
T
Reset Timer
T
RST
RESET
0.3
C
T
0.7
C
T
1.5
C
T
ms
Clock Pulse Width
T
W
CK
3
s
Note1: The unit for C
T
is F, the unit for R
T
is k.
*1 See EXAMPLE OF APPLICATION CIRCUIT(1)
Note2: The specification values of power-on reset, watchdog timer and reset timer above are intended to guarantee
the IC itself. Note that the fluctuations of C
T
and R
T
values should be taken into consideration for practical
use of the IC.
TA8044AF
2002-02-27
10
TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor
devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical
stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of
safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of
such TOSHIBA products could cause loss of human life, bodily injury or damage to property.
In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as
set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and
conditions set forth in the "Handling Guide for Semiconductor Devices," or "TOSHIBA Semiconductor Reliability
Handbook" etc..
The information contained herein is presented only as a guide for the applications of our products. No
responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other
rights of the third parties which may result from its use. No license is granted by implication or otherwise under
any intellectual property or other rights of TOSHIBA CORPORATION or others.
The information contained herein is subject to change without notice.
000707EAA_S
RESTRICTIONS ON PRODUCT USE
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