|
|
PDF TC18C43 Data sheet ( Hoja de datos )
| Número de pieza | TC18C43 | |
| Descripción | BiCMOS CURRENT MODE PWM CONTROLLERS | |
| Fabricantes | TelCom | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de TC18C43 (archivo pdf) en la parte inferior de esta página. Total 7 Páginas | ||
|
No Preview Available !
1TC18C43
TC28C43
TC38C43
BiCMOS CURRENT MODE PWM CONTROLLERS
FEATURES
GENERAL DESCRIPTION
2
s Low Power BiCMOS Design
s Tough CMOSTM Construction
s Low Supply Current ............. 1.0mA Typ @ 100kHz
s Wide Supply Voltage Operation .............. 8V to 15V
s Latch-Up Immunity ................... 500mA on Outputs
s Input Will Withstand Negative Inputs to – 5 Volts
s High Output Drive .................................... 0.7A Peak
(1.2A on 14-Pin and 16-Pin Versions)
s 2 kV ESD Protection
s Current Mode Control
s Fast Rise/Fall Time (Max) ........... 60nsec @ 1000pF
s High Frequency Operation ..........................500kHz
s Clock Ramp Reset Current ................. 2.5mA ±10%
s Low Propagation Delay Current Amp
to Output ............................................ 140nsec Typ.
s Pin Compatible with UC3843
ORDERING INFORMATION
Part No.
TC18C43MJA
TC18C43MJD
TC28C43EOE
TC28C43EPA
TC28C43EPD
Package
Temperature
8-Pin CerDIP
14-Pin CerDIP
– 55°C to +125°C
– 55°C to +125°C
16-Pin SOIC (Wide) – 40°C to +85°C
8-Pin Plastic DIP – 40°C to +85°C
14-Pin Plastic DIP – 40°C to +85°C
The TC38C43 is a current mode BiCMOS PWM control
IC. With a low 1.0 mA supply current along with high drive
current (0.7A peak) it provides a low cost solution for a PWM
that operates to 500 kHz and directly drives MOSFETs up to
HEX 3 size.
Performance of the oscillator and current sense ampli-
fier have been greatly improved over previous bipolar ver-
sions. Voltage and temperature stability have been im-
proved by a factor of 3. Noise immunity (PSRR) has also
been improved.
The TC38C43 is pin compatible with the earlier bipolar
version so that designers can easily update older designs.
Improvements have been added, though. For example,
clock ramp reset current is specified at 2.5mA (±10%) for
accurate dead time control. A few component values must
be changed (RT & CT) to use the TC38C43 in existing bipolar
designs.
The 14-pin DIP and 16-pin SOIC versions have sepa-
rate and internally isolated grounds, and are rated for higher
output current (1.2A). These separate grounds allow for
‘bootstrap’ operation of the PWM to further improve effi-
ciency.
FUNCTIONAL BLOCK DIAGRAM
3
4
5
TC38C43COE
TC38C43CPA
TC38C43CPD
16-Pin SOIC (Wide)
8-Pin Plastic DIP
14-Pin Plastic DIP
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN CONFIGURATIONS
8-Pin Plastic DIP
16-Pin SOIC (Wide)
CMPTR 1
VFB
ISENSE
RT / CT
2
3
4
TC18CMJA
TC28CEPA
TC38CCPA
8 VREF
7 VIN
6 OUTPUT
5 GND
14-Pin Plastic DIP
CMPTR 1
NC 2
14 VREF
13 NC
NC
NC
CMPTR
VFB
ISENSE
RT / CT
NC
NC
VFB 3
NC 4
ISENSE 5
NC 6
RT / CT 7
TC18CMJD
TC28CEPD
TC38CCPD
12 VIN
11 VDD
10 OUTPUT
9 GND
8 POWER
GND
1
2
3
4
5
6
7
8
TC28CCOE
TC38CEOE
16 NC
15 VREF
14 VIN
13 VDD
12 OUTPUT
11 GND
10 POWER
GND
9 NC
ANALOG
GND 9
VIN
12
VREF
VREF
14
RT/CT
7
OSC
2.5V 1.4V
UNDER VOLTAGE UV GOOD
SECTION
CLK
11 VDD
10 OUTPUT
8 POWER
GROUND
0.4V
SENSE
5
–
+
PWM COMPARATOR
+
SQ
–
CLK
R
ERROR AMP
2.5V +
VFB 3
–
COMP
1
2R
LIMIT BUFFER
+ 1.4V
–
R
PIN NUMBERS FOR
14-PIN DIP
6
7
8
TELCOM SEMICONDUCTOR, INC.
TC38C43-7 10/21/96
4-93
Free Datasheet http://www.datasheet4u.com/
1 page  
BiCMOS CURRENT MODE
PWM CONTROLLERS
1TC18C43
TC28C43
TC38C43
Dead Time
The value of RT has an effect on the discharge rate but
the primary consideration is the value of CT. The time
required to discharge the capacitor is approximately 1000
CT.
UNDERVOLTAGE LOCKOUT RANGE
VIN
TCx8C43
VON = 8.4V
VOFF = 7.6V
IS
1mA
TCx8C43
170µA
8.4 V
7.6V
VDD
Undervoltage Lockout Range
The TCx8C43 PWM Controller is used where wide
ranges of input voltage is not required. The range from
starting Vin voltage threshold to under voltage threshold is
approximately 9.5% of the starting voltage. The typical start-
up voltage is 8.4V and dropout voltage is 7.6V. This range
is used most in DC-to-DC converter applications.
Duty Cycle Limit
The TCx8C43 PWM Controller has a duty cycle limit
maximum of 99%. The oscillator is running at the same
frequency as the output.
CURRENT SENSE CIRCUIT
R
RS C
ISENSE
5
0.4V
–+
PWM
COMPARATOR
+
–
GND
9
2R
ERROR AMP
R
LIMIT BUFFER
+ 1.4V
–
Current is sensed through voltage drop across resistor
RS. A small RC filter may be required to suppress switching
transient. This voltage enters PWM Controller at ISENSE,
pin 5. A voltage of 0.4 V is added before this is fed into PWM
Comparator (+) input. The PWM Comparator (–) input
senses the voltage feedback error amp output with a limit
buffer that limits this voltage to 1.4V maximum. This limit
buffer limits the peak current across RS to a maximum of
0.95V. In normal operation, the error amplifier controls the
current limit threshold.
SHUTDOWN METHODS
2
3
TCx38C43
TCx38C43
14
VREF
5k
SHUTDOWN
ISENSE
5.1k 5
1
CMPTR
ANALOG
9 GND
4
SHUTDOWN
TO CURRENT
SENSE RESISTOR
5
Shutdown can be accomplished by either pulling ISENSE
above 1 volt or pulling CMPTR, pin 1 to GND. This will set the
PWM latch so that the output will remain low until the next
clock pulse after the shutdown condition is removed.
BENCH TEST OPERATIONAL SIMULATION
6
The timing ramp (RT/CT) is buffered by the emitter
fullpower and fed back to the ISENSE input. This ramp
simulates the dI/dT current ramp which would flow through
the primary of the transformer. The output voltage of the
power supply is simulated by feeding some of the reference
voltage into VFB. The combination of the two levels deter-
mined the operating characteristics of the current mode
controller.
7
PEAK CURRENT (IS) FORMULA:
0.95V
IS = RS
TELCOM SEMICONDUCTOR, INC.
8
4-97
Free Datasheet http://www.datasheet4u.com/
5 Page | ||
| Páginas | Total 7 Páginas | |
| PDF Descargar | [ Datasheet TC18C43.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| TC18C43 | BiCMOS CURRENT MODE PWM CONTROLLERS | TelCom |
| TC18C46 | CMOS CURRENT MODE PWM CONTROLLER | TelCom |
| TC18C46 | (TC18C46 / TC18C47) CMOS CURRENT MODE PWM CONTROLLER |  Teledyne |
| TC18C47 | (TC18C46 / TC18C47) CMOS CURRENT MODE PWM CONTROLLER | Teledyne |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |