ALTAIR05T-800 Datasheet, PDF (1/28 Pages) STMicroelectronics – Off-line all-primary-sensing switching regulator

ALTAIR05T-800
Off-line all-primary-sensing switching regulator
Features
■ Constant voltage and constant current output
regulation (CV/CC) with no optocoupler
■ Tight regulation also in presence of heavy load
transients
■ 800 V avalanche rugged internal power section
■ Quasi-resonant (QR) operation
■ Low standby power consumption
■ Automatic self-supply
■ Input voltage feedforward for mains-
independent cc regulation
■ Output cable drop compensation
■ SO16 package
Figure 1. Block diagram
SO16N
Applications
■ AC-DC chargers for mobile phones and other
hand-held equipments
■ Compact SMPS that requires a precise current
and/or voltage regulation
Description
ALTAIR05T-800 is a high-voltage all-primary
sensing switcher intended for operating directly
from the rectified mains with minimum external
parts. It combines a high-performance low-
voltage PWM controller chip and an 800 V
avalanche-rugged power section in the same
package.
+Vout
+Vin
Vcc
Rzcd
CDC
Rcdc
ZCD/FB
Rfb
Is tart -up
PROTECTION &
FEEDFORWARD
LOGIC
Prot
IFF
Iout
Vc
ESTIMATE
3.3 V
DEMAG
LOGIC
S/H -
+
2.5 V
R
S
Q
R
Internal supply bus
Vref
SU PPL Y
& UV LO
BLANKING
TIME
Vc
-
+
Iref
+
-
UVLO
STARTER
TURN-ON
LOGIC
LEB
S
Q
R
1V
-
IFF
+
RFF
Intern.
supp ly
bus
S UVLO
Q
R
Prot
DRAIN
COMP
IREF
Rcomp
Cref
Ccomp
GND
SOURCE
Rsense
October 2010
Doc ID 17957 Rev 1
1/28
www.st.com
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