|
|
PDF NCP1254 Data sheet ( Hoja de datos )
| Número de pieza | NCP1254 | |
| Descripción | Current-Mode PWM Controller | |
| Fabricantes | ON Semiconductor | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de NCP1254 (archivo pdf) en la parte inferior de esta página. Total 25 Páginas | ||
|
No Preview Available !
NCP1254
Product Preview
Current-Mode PWM
Controller for Off-line
Power Supplies featuring
Peak Power Excursion
The NCP1254 is a highly integrated PWM controller capable of
delivering a rugged and high performance offline power supply in a
TSOP−6 package. With a supply range up to 35 V, the controller hosts
a jittered 65−kHz switching circuitry operated in peak current mode
control. When the power on the secondary side starts to decrease, the
controller automatically folds back its switching frequency down to a
minimum level of 26 kHz. As the power further goes down, the part
enters skip cycle while freezing the peak current setpoint.
To help building rugged converters, the controller features several
key protective features: a non−dissipative Over Power Protection for a
constant maximum output current regardless of the input voltage, two
latched over voltage protection inputs − either through a dedicated pin
or via the Vcc input and a dual−level auto−recovery/latched overload/
short−circuit timer.
The controller architecture is designed to authorize a transient peak
power excursion when the current setpoint hits the limit. At this point,
the switching frequency is increased from 65 kHz to 130 kHz until the
peak event disappears. The timer duration is then modulated as the
converter crosses a peak power excursion mode (long) or undergoes a
short circuit (short).
Features
• 65−kHz Fixed−frequency Current−mode Control Operation with
130−kHz Excursion
• Internal and Adjustable Over Power Protection (OPP) Circuit
• Frequency Foldback down to 26 kHz and Skip−cycle in Light Load
Conditions
• Adjustable Slope Compensation
• Internally Fixed 4−ms Soft−start
• Fixed Timer−based Auto−recovery Overload/Short−circuit Protection
• 100% to 25% Timer Reduction from Overload to Short−circuit Fault
• Double Vcc Hiccup for a Reduced Average Power in Fault Mode
• Frequency Jittering in Normal and Frequency Foldback Modes
• Latched OVP Input for Improved Robustness and Latched OVP on Vcc
• Up to 35−V Vcc Maximum Rating
• Extremely Low No−load Standby Power
• This is a Pb−Free Device
Typical Applications
• Converters requiring peak−power capability such as printers power
supplies, ac−dc adapters for game stations.
This document contains information on a product under development. ON Semiconductor
reserves the right to change or discontinue this product without notice.
http://onsemi.com
1
TSOP−6
CASE 318G
STYLE 13
MARKING DIAGRAM
54xAYWG
G
1
54 = Specific Device Code
x = A or B
A = Assembly Location
Y = Year
W = Work Week
G = Pb−Free Package
(Note: Microdot may be in either location)
PIN CONNECTIONS
GND 1
6 DRV
FB 2
OPP/Latch 3
5 VCC
4 CS
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 2 of this data sheet.
© Semiconductor Components Industries, LLC, 2013
March, 2013 − Rev. P1
1
Publication Order Number:
NCP1254/D
1 page  
NCP1254
Table 4. ELECTRICAL CHARACTERISTICS
(For typical values TJ = 25°C, for min/max values TJ = −40°C to +125°C, Max TJ = 150°C, Vcc = 12 V unless otherwise noted)
Symbol
Rating
Pin Min
Typ Max
Unit
DRIVE OUTPUT
VDRVlow
DRV pin level at VCC close to VCC(min)
with a 33−kW resistor to GND
68 − − V
VDRVhigh
DRV pin level at VCC = VOVP − 0.2 V – DRV unloaded
CURRENT COMPARATOR
6 10 12 14 V
IIB
VLimit1
VLimit2
Input Bias Current @ 0.8 V input level on pin 4
Maximum internal current setpoint – Tj = 25°C – pin 3 grounded
Maximum internal current setpoint –
Tj from −40° to 125°C – pin 3 grounded
4 0.02 mA
4 0.744 0.8 0.856
V
4 0.72 0.8 0.88 V
VfoldI
VfreezeI
TDEL
TLEB
TSS
Default internal voltage set point for frequency foldback
trip point ≈59% of Vlimit
Internal peak current setpoint freeze (≈31% of Vlimit)
Propagation delay from current detection to gate off−state
Leading Edge Blanking Duration
Internal soft−start duration activated upon startup, auto−recovery
4
4
4
4
−
475 mV
250 mV
100 150 ns
300 ns
4 ms
IOPPo
Setpoint decrease for pin 3 biased to –250 mV (Note 3)
4
31.3
%
IOOPv
IOOPv
Voltage setpoint for pin 3 biased to −250 mV (Note 3), Tj = 25°C
Voltage setpoint for pin 3 biased to −250 mV (Note 3),
Tj from −40° to 125°C
4 0.51 0.55
0.6
4 0.5 0.55 0.62
V
V
IOPPs
Setpoint decrease for pin 3 grounded
40
%
INTERNAL OSCILLATOR
fOSC,nom
Oscillation frequency, VFB < VFbtrans, pin 3 grounded
VFBtrans
Feedback voltage above which Fsw increases
fOSC,max
Maximum oscillation frequency for VFB above VFBmax
VFBmax
Feedback voltage above which Fsw is constant
Dmax
Maximum duty ratio
fjitter Frequency jittering in percentage of fOSC
fswing
Swing frequency over the whole frequency range
FEEDBACK SECTION
− 61 65 71 kHz
− 3.2
V
− 120 130 140 kHz
− 3.8 4.1 4.2
V
− 76 80 84 %
− ±5
%
− 240 Hz
Rup
Internal pull−up resistor
2 15 kW
Req
Equivalent ac resistor from FB to gnd
2 13 kW
Iratio
Pin 2 to current setpoint division ratio
−4
VfreezeF
Feedback voltage below which the peak current is frozen
2
1
V
FREQUENCY FOLDBACK
VfoldF
Frequency foldback level on the feedback pin –
≈59% of maximum peak current
−
1.9
V
Ftrans
Vfold,end
Vskip
Skip
hysteresis
Transition frequency below which skip−cycle occurs
End of frequency foldback feedback level, Fsw = Fmin
Skip−cycle level voltage on the feedback pin
Hysteresis on the skip comparator (Note 2)
− 22 26 30 kHz
1.5 V
− 400 mV
− 30 mV
2. Guaranteed by design
3. See characterization table for linearity over negative bias voltage – we recommend keeping the level on pin 3 below −300 mV.
4. A 1−MW resistor is connected from pin 4 to the ground for the measurement.
http://onsemi.com
5
5 Page 
NCP1254
TYPICAL CHARACTERISTICS
158 33.7
148
138
128
118
108
98
88
−50 −25 0 25 50 75 100
JUNCTION TEMPERATURE (°C)
Figure 27.
125
33.2
32.7
32.2
31.7
31.2
30.7
−50 −25 0 25 50 75 100
JUNCTION TEMPERATURE (°C)
Figure 28.
125
http://onsemi.com
11
11 Page | ||
| Páginas | Total 25 Páginas | |
| PDF Descargar | [ Datasheet NCP1254.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| NCP1250 | Current-Mode PWM Controller | ON Semiconductor |
| NCP1251 | Current-Mode PWM Controller | ON Semiconductor |
| NCP1252 | Current Mode PWM Controller | ON Semiconductor |
| NCP1253 | Current-Mode PWM Controller | ON Semiconductor |
| 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 |