TA1307P
TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic
TA1307P
Integrated Circuit For Standby Power-Supply Control
TA1307P is a switching power-supply IC used as a standby
power-supply control such as small power-supply.
This IC, Slight power-supply can do that a MOSFET is
controlled in intermittent, and this IC is optimum IC as objects
for power-supply control, such as color TV, monitor, VCR, DVD,
FAX, printer, etc.
Main Characteristics
·
·
·
Burst mode PWM pulse output
The over current protection circuits to power MOSFET for a
drive are built in.
UVLO (Under Voltage Lock Out), OVLO (Over Voltage Lock
Out) with Latch, OVLO on/off function
OCL (Over Current Limmiter),
Select SW for IC active/IC not active are built in.
·
·
The starting current until UVLO is canceled about 100 µA.
Wide range input voltage: (85 V to 264 V).
Weight: 0.5 g (typ.)
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TA1307P
Stand Power Supply Application Circuit Example
(voltage detection by 2nd side)
Pulse out
GND2
GND1
8
7
6
OCL
5
Pulse output
Band
gap
UVLO
7 V/5 V
UVLO
12 V Latch
OSC establish
OSC
Output stop
0.2 V
3 V (pulse output stop)
/2.5 V (pulse output start)
Standby ON/OFF
V
out
Standby SW
FB
V
cc
1
0.01
mF
20
mF
2
3
0.01
mF
4
Hi: Standby OFF mode
…IC not active
Pin2 (OSC establish)
Low: Standby ON mode (OVLO off) …IC active
Outside resistance use
±2%
Open: Standby ON mode (OVLO on) …IC active
3 V (fix)
=
Upper limit DC for FB comparator
FB IN
2.5 V (fix)
=
Lower limit DC for FB comparator
PULSE
Output
expansion
OSC Wave
PULSE
Output
FB IN
(V
out
)
Figure 1
Movement Explain
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TA1307P
With outputting burst switching control pulse from IC, burst enegize of the TRANS is carried out.
Voltage stabilized also at the time of a light load can be supplied.
It is the optimum IC for constituting the power-supply system for minute electric-power supply.
By this IC, the burst time of switching control pulse is decided by level of output ripple of a power-supply system.
As for the terminal 4 which is carrying out the monitor of the power-supply output-voltage value, another side is
connected to the comparator.
The standard voltage value of this comparator has hysterisis, 2.5 V and 3 V fixation. (inside IC)
Since output DC voltage of a power supply is stabilized, power-supply output voltage is detected and it feedbacks
for the terminal 4 (FB IN terminal).
When the voltage value of a terminal 4 tends to become more than 3 V, switching control pulse of a terminal 7
(pulse out) is stopped.
If pulse is stooped, in order not to control power-supply TRANS, it will stop supplying energy supplied to the output
of a power supply, and the output DC voltage of a power-supply will descend.
If output DC voltage tends to become less than (V/2.5), switching control pulse of a terminal 7 (pulse out) will be
outputted.
Power-supply TRANS is made to drive and PULSE supplies energy to a power-supply output.
Then, output DC voltage rises.
Burst electric supply is realized by repeating the above-mentioned operation.
V
out
V
cc
I
C
R2
I
F
V
F
FB
4
I
z
V
z
=
3.9 V
R1
Is
R3
FB comparater
V
ref
2.5 V/3 V
Figure 2
Ripple Voltage Establish
(example)
Hereafter, calculation using ripple level as an example
Voltage of V
out
and the terminal 2 is set output DC voltage to V
ref
.
V
out
=
V
z
+
V
F
+
1/CTR
´
R2/R1
´
V
ref
*CTR
=
I
C
/I
F
*I
Z
=
I
F
+
I
S
, R3 is set up.
For example, R1
=
10 kW, R2
=
R3
=
1 kW, CTR
=
about 1, V
z
=
3.9 V, V
F
=
0.7 V
V
ref
(minimum)
=
2.5 V fixation and V
ref
(maximum)
=
3 V fixation.
Calculation
V
out
(minimum)
=
4.85 V
V
out
(maximum)
=
4.9 V.
Ripple in an output is 0.05 V.
Internal oscillation circuit for obtaining output PULSE is built in.
Oscillation frequency of output PULSE can be set up by outside attachment resistance to a terminal 2.
Duty about 50% of output PULSE has been obtained.
Oscillation frequency is calculation from f
=
i/2 CV (Hz), I
=
1 (V) /R/10, and it will be set to 25 kHz, if 20 kW is
attached to a terminal 2 outside.
Terminal voltage and R are outside attachment resistance in 1 (V).
10 is a current ratio, sets current of a terminal 2 to 1/10, and makes it the charge/discharge current of a internal
50 pF capacitor. C
=
50 (pF) (built-in capacitor value) V
=
2 (V) (oscillation amplitude)
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TA1307P
In addition, there is a function below as a PROTECT circuits.
A terminal 5 (OCL) detects the overcurrent of MOSFET connected to the terminal 7 (pulse out), and output Pulse
is made to compulsion low at the time of an overcurrent.
Output pulse will be made to compulsion low, if it flows into a terminal 7 (pulse out) and there is always 40 mA or
more of current.
Output pulse will be made to compulsion low, if the supply voltage of a terminal 1 (V
CC
) becomes more than
12 V.(OVLO)
Circuit operation start of the UVLO function is carried out more than by 7 V, and it carries out a circuit operation
stop less than 5 V.
Pin Connection
(top view)
V
CC
OSC establish
Standby SW
FB IN
1
2
3
4
8
7
6
5
GND2
Pulse OUT
GND1
OCL
Pin2 (OSC establish)
Outside resistance use
±2%
Maximum Ratings
(Ta
=
25°C)
Characteristics
Supply Voltage
Maximum Input Voltage
Minimun Input Voltage
Power Dissipation
Operating Temperature
Storage Temperature
(Note 1)
Symbol
V
CC
max
V
IN
max
V
IN
min
P
D
max
T
opr
T
stg
Rating
14
V
CC
+
0.3
GND
-
0.3
817
-25~85
-55~150
Unit
V
V
V
mW
°C
°C
Note 1: Derated above Ta
=
25°C in the proportion of 6.5 mW/°C
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TA1307P
817
(mW)
Power dissipation
P
D
425
0
25
85
150
Ta (
°C
)
Figure 3
Recommended Operating Condition
Characteristics
Power Supply Voltage
Pin
No.
1
Min
7.5
P
D
-
Ta Curve
Typ.
¾
Max
11.5
Unit
V
Electrical Characteristics
DC Characteristics
(There is no designation V
cc
=
9 V, Ta
=
25°C)
(reference:
a measurement circuit is figure 4)
Characteristics
Power Current (9 V)
Symbol
I1Load
Pin
No.
1
Test Condition
Load of 100 pF is connected with Pin7.
SW1
=
ON, SW2
=
b, SW3
=
a
Pin3
=
Low voltage input
(standby ON mode)
SW1
=
ON, SW2
=
b, SW3
=
b
Power Current (9 V)
I1off
1
Pin3 = Hi voltage input
(standby OFF mode)
SW1
=
Open, SW2
=
a, SW3
=
b
V3th L
Pin3 Threshold Voltage
V3th H
3
(Note 3)
(Note 2)
¾
0.9
0.7
0.7
0.5
¾
V
0.05
0.09
0.13
mA
Min
0.8
Typ.
1.2
Max
1.6
Unit
mA
Power Current (9 V)
I1on
1
0.39
0.55
0.72
mA
Note 2: V3 th L is threshold voltage “Standby ON (IC active) mode”
Note 3: V3 th H is threshold voltage “Standby OFF (IC not active) mode”
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