GRUNDIG Cinemo 40 LCD television Power supply circuit – L6598 – VIPer22 - LCD television repair and service
Category: LCD Television Repair and service
Contents of this article
- L6598 Smps driver ic
- VIPer22
- Power supply Schematic diagram
GRUNDIG Cinemo 40
L6598 High voltage resonant controller
Description
The L6598 device is manufactured with the BCD offline technology, able to ensure voltage ratings up to 600 V, making it perfectly suited for AC/DC adapters and wherever a resonant topology can be beneficial. The device is intended to drive two power MOSFETs, in the classical half bridge topology. A dedicated timing section allows the designer to set soft-start time, soft-start and minimum frequency. An error amplifier, together with the two enable inputs, are made available. In addition, the integrated bootstrap diode and the Zener clamping on low voltage supply, reduces to a minimum the external parts needed in the applications.
The L6598 device is manufactured with the BCD offline technology, able to ensure voltage ratings up to 600 V, making it perfectly suited for AC/DC adapters and wherever a resonant topology can be beneficial. The device is intended to drive two power MOSFETs, in the classical half bridge topology. A dedicated timing section allows the designer to set soft-start time, soft-start and minimum frequency. An error amplifier, together with the two enable inputs, are made available. In addition, the integrated bootstrap diode and the Zener clamping on low voltage supply, reduces to a minimum the external parts needed in the applications.
# High voltage rail up to 600 V
# dV/dt immunity ±50 V/ns in full temperature range
# Driver current capability: 250 mA source 450 mA sink
# Switching times 80/40 ns rise/fall with 1 nF load
# CMOS shutdown input
# Undervoltage lockout
# Soft-start frequency shifting timing
# dV/dt immunity ±50 V/ns in full temperature range
# Driver current capability: 250 mA source 450 mA sink
# Switching times 80/40 ns rise/fall with 1 nF load
# CMOS shutdown input
# Undervoltage lockout
# Soft-start frequency shifting timing
PIN CONFIGARATION AND FUNCTION
Pin
no.
|
Name
|
Function
|
1
|
CSS
|
Soft-start
timing capacitor
|
2
|
R fstart
|
Soft-start
frequency setting - low impedance voltage source -see also Cf
|
3
|
C f
|
Oscillator
frequency setting - see also Rfmin, Rfstart
|
4
|
R fmin
|
Minimum
oscillation frequency setting - low impedance voltage source - see also Cf
|
5
|
O Pout
|
Sense
op amp output - low impedance
|
6
|
O Pon-
|
Sense
op amp inverting input -high impedance
|
7
|
O Pon+
|
Sense
op amp non inverting input - high impedance
|
8
|
EN1
|
Half
bridge latched enable
|
9
|
EN2
|
Half
bridge unlatched enable
|
10
|
GND
|
Ground
|
11
|
LVG
|
Low
side driver output
|
12
|
V s
|
Supply
voltage with internal Zener clamp
|
13
|
N.C.
|
Not
connected
|
14
|
OUT
|
High
side driver reference
|
15
|
HVG
|
High
side driver output
|
16
|
V boot
|
Bootstrapped
supply voltage
|
VIPer22A Low power OFF-line SMPS switcher
Description
The VIPer22A-E combines a dedicated current mode PWM controller with a high voltage power MOSFET on the same silicon chip.
The VIPer22A-E combines a dedicated current mode PWM controller with a high voltage power MOSFET on the same silicon chip.
Typical applications cover off line power
supplies for battery charger adapters, standby power supplies for TV or
monitors, auxiliary supplies for motor control, etc. The internal control
circuit offers the following benefits: Large input voltage range on the VDD pin
accommodates changes in auxiliary supply voltage. This feature is well adapted
to battery charger adapter configurations. Automatic burst mode in low load
condition. Overvoltage protection in HICCUP mode.
# Fixed 60 kHz switching frequency
# 9 V to 38 V wide range VDD voltage
# Current mode control
# Auxiliary undervoltage lockout with hysteresis
# High voltage start-up current source
# Overtemperature, overcurrent and overvoltage
# protection with auto-restart
# 9 V to 38 V wide range VDD voltage
# Current mode control
# Auxiliary undervoltage lockout with hysteresis
# High voltage start-up current source
# Overtemperature, overcurrent and overvoltage
# protection with auto-restart
PIN CONFIGRATION AND FUNCTION
Pin
Name
|
Pin
function
|
V DD
|
Power
supply of the control circuits. Also provides a charging current during start
up
thanks to a high voltage current source connected to the drain. For this purpose, an hysteresis comparator monitors the VDD voltage and provides two thresholds: - V DDon: Voltage value (typically 14.5 V) at which the device starts switching and turns off the start up current source. - V DDoff: Voltage value (typically 8 V) at which the device stops switching and turns on the start up current source. |
SOURCE
|
Power
MOSFET source and circuit ground reference.
|
DRAIN
|
Power
MOSFET drain. Also used by the internal high voltage current source during
start up phase for charging the external VDD capacitor. |
FB
|
Feedback
input. The useful voltage range extends from 0 V to 1 V, and defines the
peak drain MOSFET current. The current limitation, which corresponds to the maximum drain current, is obtained for a FB pin shorted to the SOURCE pin. |
