SGS Thomson Microelectronics TEA5170 Datasheet
SWITCH MO DE POWER SUPPLY SECONDARY C IRCUIT
.
INTERNAL PWM SIGNAL GENERATOR
.
POWER SU PPLY WIDE RANG E 4.5V – 14.5V
.
SOFT START
.
REFERENCE VOLTAGE 2V ± 5%
.
WIDE FREQUENCY RANGE 250kHz
.
MINIMUM OUTPUT PULSE WIDTH 500nS
.
MAXIMUM PRESET DUTY CYCLE
.
SYNCHRONIZATION WINDOW
.
OUTPUT SWI TCH
.
UNDERVOLTAGE LOCKOUT
.
FREQUENCY RANGE WITH SYNCHR ONIZATION 64kHz
DESCRIPTION
The TEA5170 is designed to work in the secondary
part of an off-line SMPS, sending pulses to the
slaved TEA2260/61 which are located on the primary side of the main transformer. An accurate
regulated voltage is obtained by duty cycle control.
The TEA5170 can be externally synchronized by
higher or lower frequency signal, then it could be
used in applications like TV set ones. For more
details, refer to application note AN408/0591.
TEA5170
DIP8
(Plastic Package)
ORDER CODE : TEA5170
PIN CONNECTIONS
SOFT-START CAPACITOR
SUPPLY VOLTAGE
POWER OUTPUT
GROUND
September 1993
CSF
V
CC
P
GND
1
2
3
4
8
7
6
5
OSCILLATOR RESISTOR
RT
OSCILLATOR CAPACITOR
CT
VOLTAGE ERROR AMPLIFIER OUTPUT
E
OUTOUT
VOLTAGE ERROR AMPLIFIER
E
INVERTING INPUT
5170-01.EPS
1/9
TEA5170
BLOCK DIAG RAM
7
Ct
OSCILLATOR
Rt
8
LOGIC
(SYNCHRO)
Comparator
POWER OUTPUT
STAGE
2.7V
Csf
1
SOF T ST ART AN D
DUTY CYCLE LIMITING
PWM
LOGIC
Error Amplifier
E-
5
x -1
2V
PWM
VMonitor
CC
642 3
Eout GND
V
CC
P
out
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
CC
T
T
stg
Supply Voltage 15 V
Operating Junction Temperature 150 °C
j
Storage Temperature Range – 40, + 150 °C
THERMAL D ATA
Symbol Parameter Value Unit
R
th (j-a)
Junction-ambient Thermal Resistance 90 °C/W
5170-02.EPS
5170-01.TBL
5170-02.TBL
RECOMMAN DED OPE R ATING CO NDIT IO NS
Symbol Parameter Min. Typ. Max. Unit
V
CC
RT Timing Resistor 47 180 kΩ
CT Timing Capacitor 0.12 1.8 nF
Fosc Oscillator Frequency 12 250 kHz
Fsy Synchro Frequency 12 64 kHz
T
amb
VRT Voltage on Pin RT (8) 7 Volt
VCT Current on Pin CT (1) 100 µA
I
SOURCE
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Power Supply Voltage 5 14 V
Operating Ambient Temperature – 20 70 °C
Output Current 30 60 mA
5170-03.TBL
TEA5170
ELECTRICAL CHARACTERISTICS (TA = 25oC, VCC = 12V, unless otherwise specified)
Symbol Parameter Test Conditions Min. Typ. Max. Unit
OSCILLATOR
TA Free Period RT = 100kΩ ± 0%
CT = 1.2nF ± 0%, Vcc = 12V
TB RT = 100kΩ ± 0%
CT = 560pF ± 0%, Vcc = 12V
∆F
OSC
(T)
∆F
OSC
(VCC)
Frequency drift due to ambient
temperature variation from 0oC to 70oC
F
(70oC) − F
OSC
70
o
C x F
OSC
OSC
(25oC)
Frequency drift due to VCC variation
from 5V to 12V
(12V) − F
F
OSC
7V x F
OSC
OSC
(12V)
ERROR VOLTAGE AMPLIFIER (V
(0oC)
(5V)
CC
= 12V)
RT = 100kΩ ± 0%
CT = 1.2nF ± 0%, Vcc = 12V
RT = 100kΩ ± 0%
CT = 1.2nF ± 0%
Ibias Input Bias Current Ein = 2V 0 0.2 1 µA
Gvol Voltage Gain 80 dB
GB Gain Bandwidth 2 MHz
Slew Rate 2V/µs
INTERNAL VOLTAGE REFERENCE
V
REF
∆V
(VCC) Line Regulation
REF
∆V
REF
T
ON MIN
T
ONMIN A
T
ONMIN B
Voltage Reference Using the voltage error
amplifier as a follower
(T) V
drift with temperature
REF
V
(70oC) − V
REF
70
o
C
V
REF
REF
(12V) − V
7V
(0oC)
REF
(5V)
VCC = 5V to 12V – 3 0.4 3 mV/V
TA = 0°C to 70°C 0.2 mV/°
Minimum Duty Cycle Ct = 1.2nF ± 0%
Rt = 100kΩ ± 0%
Minimum Duty Cycle Ct = 560pf ± 0%
Rt = 100kΩ ± 0%
POWER OUTPUT STAGE
V
POUTH
V
POUTL
I
SINK
I
SOURCE
Output High Level I
Output Low Level I
Sink Current V
Source Current V
= 1mA 6.3 6.9 7.5 V
load
= – 1mA 0.5 0.8 1.1 V
load
= 3V 30 60 190 mA
POUT
= 3V 30 110 190 mA
POUT
SYNCHRONISATION
F
trig Max
V
trig
T
trigp
Wtrig +
Wtrig –
Maximum Synchro Frequency 64 kHz
Synchro Triggering Threshold 2.7 3 V
Synchro Triggering Pulse Width at VRT = 2.7Volt (fig 5) 800 nS
T
− T
trig+
O
Positive Triggering Window
Negative Triggering Window
T
O
T
− T
O
T
O
CT = 1.2nF ± 0%
RT = 100kΩ ± 0%
−
trig
CT = 1.2nF ± 0%
RT = 100kΩ ± 0%
SOFT START
I
csf
Donmax Maximum Duty Cycle V
*Csf Load Current V
= 1V 2.5 3.7 6 µA
csf
> 2.5V, VCC = 12V
cs
CT = 1.2nf ± 0%
RT = 100kΩ ± 0%
*Csf is a high impedance capacitor
60.40 65.60 70.80 µS
29.18 31.70 34.22 µS
0.01 %/°C
0.07 %/V
1.9 2 2.1 V
1.77 2.53 3.29 µs
1.04 1.49 1.94 µs
25 35 40 %
92942%
60 78 95 %
5170-04.TBL
3/9
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