ALTAIR05T-800TR STMicroelectronics, ALTAIR05T-800TR Datasheet - Page 4

• Manufacturer Part Number: ALTAIR05T-800TR
• Description: Switching Converters, Regulators & Controllers 800V Off-line QR Switching Regulator
• Manufacturer: STMicroelectronics

Specifications of ALTAIR05T-800TR

• Input Voltage: 11.5 V to 23 V
• Switching Frequency: 166 KHz
• Operating Temperature Range: - 55 C to + 150 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-16
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Pin connection
2
Note:
Table 1.
4/28
1, 2
N.
3
4
5
SOURCE
Name
GND
IREF
Vcc
Pin connection
Figure 2.
The copper area for heat dissipation has to be designed under the drain pins
Pin functions
Power section source and input to the PWM comparator. The current flowing in the MOSFET
is sensed through a resistor connected between the pin and GND. The resulting voltage is
compared with an internal reference (0.75V max.) to determine MOSFET’s turn-off. The pin
is equipped with 250 ns blanking time after the gate-drive output goes high for improved
noise immunity. If a second comparison level located at 1V is exceeded the IC is stopped and
restarted after Vcc has dropped below 5V.
Supply Voltage of the device. An electrolytic capacitor, connected between this pin and
ground, is initially charged by the internal high-voltage start-up generator; when the device is
running the same generator keeps it charged in case the voltage supplied by the auxiliary
winding is not sufficient. This feature is disabled in case a protection is tripped. Sometimes a
small bypass capacitor (0.1 µF typ.) to GND might be useful to get a clean bias voltage for
the signal part of the IC.
Ground. Current return for both the signal part of the IC and the gate drive. All of the ground
connections of the bias components should be tied to a trace going to this pin and kept
separate from any pulsed current return.
CC regulation loop reference voltage. An external capacitor has to be connected between
this pin and GND. An internal circuit develops a voltage on this capacitor that is used as the
reference for the MOSFET’s peak drain current during CC regulation. The voltage is
automatically adjusted to keep the average output current constant.
Pin connection (top view)
SOURCE
SOURCE
SOURCE
SOURCE
ZCD/FB
ZCD/FB
Doc ID 17957 Rev 1
COMP
COMP
CDC
CDC
IREF
IREF
GND
GND
Vcc
Vcc
1
1
1
2
2
2
3
3
3
4
4
4
5
5
5
6
6
6
7
7
7
8
8
8
Function
16
16
16
15
15
15
14
14
14
13
13
13
12
12
12
11
11
11
10
10
10
9
9
9
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
DRAIN
N.C.
N.C.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
ALTAIR05T-800