VIPER100ASP-E STMicroelectronics, VIPER100ASP-E Datasheet - Page 12

• Manufacturer Part Number: VIPER100ASP-E
• Description: IC SWIT PWM SMPS CM POWERSO10
• Manufacturer: STMicroelectronics
• Series: VIPER™r

Specifications of VIPER100ASP-E

• Output Isolation: Isolated
• Frequency Range: 90 ~ 200kHz
• Voltage - Input: 8 ~ 15 V
• Voltage - Output: 700V
• Power (watts): 82W
• Operating Temperature: 25°C ~ 125°C
• Package / Case: PowerSO-10 Exposed Bottom Pad
• Number Of Outputs: 1
• Output Voltage: 700 V
• Output Current: 3000 mA
• Mounting Style: SMD/SMT
• Switching Frequency: 90 KHz to 110 KHz
• Operating Supply Voltage: 0 V to 15 V
• Fall Time: 100 ns
• Rise Time: 50 ns
• Synchronous Pin: No
• Pwm Type: Current Mode PWM Controller
• Number Of Pwm Outputs: 1
• On/off Pin: No
• Adjustable Output: No
• Switching Freq: 90 TO 110kHz
• Operating Supply Voltage (max): 15V
• Mounting: Surface Mount
• Pin Count: 10
• Package Type: PowerSO
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6790-5; VIPER100ASP-E

5 Operation Description
5.3
12/31
As soon as the power goes below this limit, the auxiliary secondary voltage starts to increase
above the 13V regulation level, forcing the output voltage of the transconductance amplifier to
low state (V
switch is maintained in the Off state, resulting in missing cycles and zero duty cycle. As soon as
V
operates again. The above cycle repeats indefinitely, providing a burst mode of which the
effective duty cycle is much lower than the minimum one when in normal operation. The
equivalent switching frequency is also lower than the normal one, leading to a reduced
consumption on the input main supply lines. This mode of operation allows the VIPer100A-E/
ASP-E to meet the new German "Blue Angel" Norm with less than 1W total power consumption
for the system when working in stand-by mode. The output voltage remains regulated around
the normal level, with a low frequency ripple corresponding to the burst mode. The amplitude of
this ripple is low, because of the output capacitors and low output current drawn in such
conditions.The normal operation resumes automatically when the power gets back to higher
levels than P
High Voltage Start-up Current Source
An integrated high voltage current source provides a bias current from the DRAIN pin during
the start-up phase. This current is partially absorbed by internal control circuits which are
placed into a standby mode with reduced consumption and also provided to the external
capacitor connected to the V
threshold V
start-up current generator is switched off, and the converter should normally provide the
needed current on the V
(see Figure
In case there are abnormal conditions where the auxiliary winding is unable to provide the low
voltage supply current to the V
external capacitor discharges to the low threshold voltage V
device goes back to the inactive state where the internal circuits are in standby mode and the
start-up current source is activated. The converter enters a endless start-up cycle, with a start-
up duty cycle defined by the ratio of charging current towards discharging when the device tries
to start. This ratio is fixed by design to 2A to 15A, which gives a 12% start-up duty cycle while
the power dissipation at start-up is approximately 0.6W, for a 230Vrms input voltage.
This low value start-up duty cycle prevents the application of stress to the output rectifiers as
well as the transformer when a short circuit occurs.
The external capacitor C
converter to start up, when the device starts switching. This time t
parameters, among which transformer design, output capacitors, soft start feature, and
compensation network implemented on the COMP pin. The following formula can be used for
defining the minimum capacitor needed:
where:
I
values.
t
generally at full load.
DD
SS
DD
is the start up time of the converter when the device begins to switch. Worst case is
is the consumption current on the V
gets back to the regulation level and the V
C
VD D
DDon
COMP
11).
STBY
of the UVLO logic, the device becomes active mode and starts switching. The
--------------------
V
.
I
< V
DD
DD hyst
t
COMPth
SS
DD
VDD
pin through the auxiliary winding of the transformer, as shown on
). This situation leads to the shutdown mode where the power
DD
on the V
DD
pin. As soon as the voltage on this pin reaches the high voltage
pin (i.e. short circuit on the output of the converter), the
DD
DD
pin must be sized according to the time needed by the
pin when switching. Refer to specified I
COMPth
threshold is reached, the device
DDoff
of the UVLO logic, and the
SS
depends on many
VIPer100A-E/ASP-E
DD1
and I
DD
2