Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

ISL8845AMBZ Datasheet(PDF) 10 Page - Intersil Corporation

Part # ISL8845AMBZ
Description  High Performance Industry Standard Single-Ended Current Mode PWM Controller
Download  15 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  INTERSIL [Intersil Corporation]
Direct Link  http://www.intersil.com/cda/home
Logo INTERSIL - Intersil Corporation

ISL8845AMBZ Datasheet(HTML) 10 Page - Intersil Corporation

Back Button ISL8845AMBZ Datasheet HTML 6Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 7Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 8Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 9Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 10Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 11Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 12Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 13Page - Intersil Corporation ISL8845AMBZ Datasheet HTML 14Page - Intersil Corporation Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 15 page
background image
10
FN6320.3
April 18, 2007
Pin Descriptions
RTCT - This is the oscillator timing control pin. The
operational frequency and maximum duty cycle are set by
connecting a resistor, RT, between VREF and this pin and a
timing capacitor, CT, from this pin to GND. The oscillator
produces a sawtooth waveform with a programmable
frequency range up to 2.0MHz. The charge time, tC, the
discharge time, tD, the switching frequency, f, and the
maximum duty cycle, Dmax, can be approximated from the
following equations:
The formulae have increased error at higher frequencies due
to propagation delays. Figure 4 may be used as a guideline
in selecting the capacitor and resistor values required for a
given frequency.
COMP - COMP is the output of the error amplifier and the
input of the PWM comparator. The control loop frequency
compensation network is connected between the COMP and
FB pins.
FB - The output voltage feedback is connected to the
inverting input of the error amplifier through this pin. The
non-inverting input of the error amplifier is internally tied to a
reference voltage.
CS - This is the current sense input to the PWM comparator.
The range of the input signal is nominally 0V to 1.0V and has
an internal offset of 100mV.
GND - GND is the power and small signal reference ground
for all functions.
OUT - This is the drive output to the power switching device.
It is a high current output capable of driving the gate of a
power MOSFET with peak currents of
1.0A. This GATE
output is actively held low when VDD is below the UVLO
threshold.
VDD - VDD is the power connection for the device. The total
supply current will depend on the load applied to OUT. Total
IDD current is the sum of the operating current and the
average output current. Knowing the operating frequency, f,
and the MOSFET gate charge, Qg, the average output
current can be calculated from:
To optimize noise immunity, bypass VDD to GND with a
ceramic capacitor as close to the VDD and GND pins as
possible.
VREF - The 5.00V reference voltage output. +1.0/-1.5%
tolerance over line, load and operating temperature. Bypass
to GND with a 0.1
μF to 3.3μF capacitor to filter this output as
needed.
Functional Description
Features
The ISL884xA current mode PWM makes an ideal choice for
low-cost flyback and forward topology applications. With its
greatly improved performance over industry standard parts,
it is the obvious choice for new designs or existing designs
which require updating.
Oscillator
The ISL884xA has a sawtooth oscillator with a
programmable frequency range to 2MHz, which can be
programmed with a resistor from VREF and a capacitor to
GND on the RTCT pin. (Please refer to
Figure 4 for the
resistor and capacitance required for a given frequency.)
FIGURE 3. EA REFERENCE vs TEMPERATURE
FIGURE 4. RESISTANCE FOR CT CAPACITOR VALUES GIVEN
Typical Performance Curves (Continued)
-60 -40
-20
0
20
40
60
80
100 120 140
0.996
0.997
0.998
1.000
1.001
TEMPERATURE (°C)
1
10
100
1
10
100
103
RT (k
Ω)
100pF
220pF
330pF
470pF
1.0nF
2.2nF
3.3nF
4.7nF
6.8nF
t
C
0.533 RT CT
⋅⋅
(EQ. 1)
t
D
RT
CT In
0.008 RT
3.83
0.008 RT
1.71
---------------------------------------------⎠
⋅⋅
(EQ. 2)
f
1t
C
t
D
+
()
=
(EQ. 3)
Dt
C f
=
(EQ. 4)
I
OUT
Qg
f
×
=
(EQ. 5)
ISL8840A, ISL8841A, ISL8842A, ISL8843A, ISL8844A, ISL8845A


Similar Part No. - ISL8845AMBZ

ManufacturerPart #DatasheetDescription
logo
Intersil Corporation
ISL8845AMBZ INTERSIL-ISL8845AMBZ Datasheet
309Kb / 15P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
April 18, 2007
logo
Renesas Technology Corp
ISL8845AMBZ RENESAS-ISL8845AMBZ Datasheet
716Kb / 15P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
More results

Similar Description - ISL8845AMBZ

ManufacturerPart #DatasheetDescription
logo
Intersil Corporation
ISL8840AABZ INTERSIL-ISL8840AABZ Datasheet
309Kb / 15P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
April 18, 2007
logo
Renesas Technology Corp
ISL8840A RENESAS-ISL8840A Datasheet
716Kb / 15P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
logo
Intersil Corporation
ISL8840AMZ INTERSIL-ISL8840AMZ Datasheet
229Kb / 10P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
December 1, 2011
ISL8840AMBEPZ INTERSIL-ISL8840AMBEPZ Datasheet
231Kb / 10P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
ISL78840ASRH INTERSIL-ISL78840ASRH_10 Datasheet
766Kb / 15P
   High Performance Industry Standard Single-Ended Current Mode PWM Controller
ISL8843 INTERSIL-ISL8843 Datasheet
305Kb / 12P
   Industry Standard Single-Ended Current Mode PWM Controller
ISL8843 INTERSIL-ISL8843 Datasheet
341Kb / 13P
   Industry Standard Single-Ended Current Mode PWM Controller
September 14, 2015
logo
Renesas Technology Corp
ISL8843 RENESAS-ISL8843 Datasheet
639Kb / 13P
   Industry Standard Single-Ended Current Mode PWM Controller
logo
Intersil Corporation
ISL8843 INTERSIL-ISL8843_06 Datasheet
313Kb / 12P
   Industry Standard Single-Ended Current Mode PWM Controller
ISL78840ASEH INTERSIL-ISL78840ASEH Datasheet
810Kb / 15P
   Radiation Hardened, High Performance Industry Standard Single-Ended Current Mode PWM Controller
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com