Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

LT1619 Datasheet(PDF) 7 Page - Linear Technology

Part # LT1619
Description  Low Voltage Current Mode PWM Controller
Download  20 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  LINER [Linear Technology]
Direct Link  http://www.linear.com
Logo LINER - Linear Technology

LT1619 Datasheet(HTML) 7 Page - Linear Technology

Back Button LT1619 Datasheet HTML 3Page - Linear Technology LT1619 Datasheet HTML 4Page - Linear Technology LT1619 Datasheet HTML 5Page - Linear Technology LT1619 Datasheet HTML 6Page - Linear Technology LT1619 Datasheet HTML 7Page - Linear Technology LT1619 Datasheet HTML 8Page - Linear Technology LT1619 Datasheet HTML 9Page - Linear Technology LT1619 Datasheet HTML 10Page - Linear Technology LT1619 Datasheet HTML 11Page - Linear Technology Next Button
Zoom Inzoom in Zoom Outzoom out
 7 / 20 page
background image
7
LT1619
1619fa
OPERATIO
Inductor
The value of the inductor is usually selected so that the
peak-to-peak ripple current is less than 30% of the maxi-
mum inductor current. The inductor should be able to
handle the maximum inductor current at full load without
saturation. Powder iron cores are not suitable for high
frequency switch mode power supply applications be-
cause of their high core losses. Ferrite cores have very low
core losses and are the material of choice for high fre-
quency DC/DC converters.
Power MOSFET Driver
The LT1619 is capable of driving a low side N-channel
power MOSFET with up to 60nC of total gate charge (Qg).
An external driver is recommended for MOSFETs with
greater than 80nC of total gate charge. The peak gate drive
current varies from 0.5A with VDRV = 2.5V to 1.2A with
VDRV = 10V. The MOSFET driver is capable of charging the
gate of the power MOSFET to within 350mV of the upper
gate drive supply rail (DRV). It can also pull the gate of the
MOSFET to within 100mV of ground during turnoff. The
upper supply rail of the gate drive is brought out as a device
pin (DRV) for design flexibility. In a boost converter
design, the DRV pin can be tied to the converter output if
the minimum input voltage is insufficient to fully enhance
the power MOSFET. During start-up, the MOSFET is driven
with a gate voltage starting from VIN – VD (VD is the
forward voltage of the rectifying diode). As the output
voltage rises, the gate drive also increases until steady
state is reached. If the steady-state converter output
voltage exceeds the maximum allowable gate source
voltage and the input voltage is sufficient to enhance the
MOSFET, the DRV pin is tied to the input supply. For a
SEPIC converter, the DRV pin can be tied to the input or
diode OR’ed from the input and the output (Figure 4).
Figure 4. SEPIC Converter with Diode OR’ed Gate Drive Supply
or less than the number specified in Table 1 are accept-
able. The maximum duty cycle is essentially unaffected by
synchronization.
The device will go into shutdown mode if the S/S pin
voltage stays below the shutdown threshold of 0.45V for
more than 33
µs. This shutdown delay is reset whenever
the S/S pin voltage rises above the shutdown threshold.
Applying a logic low signal at the S/S pin causes the gate
drive output to go low. Although all circuits in the LT1619
are disabled, the pull-down circuit in the MOSFET buffer is
still biased on. It is capable of shunting any leakage or
transient current at the GATE pin to ground, eliminating
the need for an external bleed resistor. The LT1619 con-
sumes 15
µA in shutdown.
The LT1619 is guaranteed to start with a minimum VIN of
1.85V. Comparator A2 senses the input voltage and gen-
erates an undervoltage lockout (UVLO) signal if VIN falls
below this minimum. While in undervoltage lockout, VC is
pulled low and the LT1619 stops switching. The supply
current drawn by the device falls to 140
µA.
Table 1. Maximum Allowable Rise Time of Synchronization
Pulse. Rise Time Can Be Slower if Clock Amplitude is Higher
SYNCHRONIZATION
MAXIMUM ALLOWABLE
AMPLITUDE (V)
RISE TIME (ns)
1.2
120
1.5
220
2.0
350
2.5
470
3.0
530
DRV
VIN
VOUT
RS
1619 F03
LT1619
GND
+
APPLICATIO S I FOR ATIO


Similar Part No. - LT1619

ManufacturerPart #DatasheetDescription
logo
Linear Technology
LT1619 LINER-LT1619 Datasheet
671Kb / 28P
   Single PoE PSE Controller High Capacitance Legacy Device Detection
LT1619 LINER-LT1619_15 Datasheet
267Kb / 20P
   Low Voltage Current Mode PWM Controller
More results

Similar Description - LT1619

ManufacturerPart #DatasheetDescription
logo
Linear Technology
LT1619 LINER-LT1619_15 Datasheet
267Kb / 20P
   Low Voltage Current Mode PWM Controller
logo
Supertex, Inc
HV9112 SUTEX-HV9112_07 Datasheet
705Kb / 8P
   High-Voltage Current-Mode PWM Controller
logo
Microchip Technology
HV9120 MICROCHIP-HV9120 Datasheet
476Kb / 18P
   High-Voltage, Current-Mode, PWM Controller
07/14/15
logo
Supertex, Inc
HV9120NG-G SUTEX-HV9120NG-G Datasheet
960Kb / 11P
   High-Voltage, Current-Mode PWM Controller
HV9120 SUTEX-HV9120 Datasheet
325Kb / 7P
   High-Voltage Current-Mode PWM Controller
HV9110 SUTEX-HV9110_07 Datasheet
706Kb / 8P
   High-Voltage Current-Mode PWM Controller
HV9123NG-G SUTEX-HV9123NG-G Datasheet
951Kb / 11P
   High-Voltage, Current-Mode PWM Controller
HV9110 SUTEX-HV9110 Datasheet
324Kb / 7P
   High-Voltage Current-Mode PWM Controller
HV9123 SUTEX-HV9123_14 Datasheet
649Kb / 11P
   High-Voltage,Current-Mode PWM Controller
logo
Anpec Electronics Corop...
APW38HC42 ANPEC-APW38HC42 Datasheet
136Kb / 11P
   CMOS Current-Mode PWM Voltage Controller
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20


Datasheet Download

Go To PDF Page


Link URL




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

About Alldatasheet   |   Advertisement   |   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