SI9102DN02-T1 VISHAY [Vishay Siliconix], SI9102DN02-T1 Datasheet - Page 5

• Manufacturer Part Number: SI9102DN02-T1
• Description: 3-W High-Voltage Switchmode Regulator
• Manufacturer: VISHAY [Vishay Siliconix]

PIN CONFIGURATIONS
DETAIL DESCRIPTION
Pre-Regulator/Start-Up Section
Due to the low quiescent current requirement of the Si9102
control circuitry, bias power can be supplied from the unreg-
ulated input power source, from an external regulated low-
voltage supply, or from an auxiliary "bootstrap" winding on
the output inductor or transformer.
When power is first applied during start-up, + V
constant current. The magnitude of this current is determined
by a high-voltage depletion MOSFET device which is con-
nected between + V
vides initial power to the IC by charging an external bypass
capacitance connected to the V
is disabled when V
exceed the 9.4 V threshold, then V
nominal value of 9.4 V by the pre-regulator circuit.
Document Number: 70001
S-70497-Rev. H, 19-Mar-07
4
5
6
7
8
CC
IN
1
2
3
4
5
6
7
exceeds 9.4 V. If V
3
9
and V
10
PLCC-20
2
Top View
PDIP-14
Top View
11
1
CC
CC
. This start-up circuitry pro-
12
20
pin. The constant current
CC
19
13
14
13
12
11
10
9
8
will be regulated to a
CC
18
17
16
15
14
is not forced to
IN
will draw a
As the supply voltage rises toward the normal operating con-
ditions, an internal undervoltage (UV) lockout circuit keeps
the output MOSFET disabled until V
voltage lockout threshold (typically 8.8 V). This guarantees
that the control logic will be functioning properly and that suf-
ficient gate drive voltage is available before the MOSFET
turns on. The design of the IC is such that the undervoltage
lockout threshold will not exceed the pre-regulator turn-off
voltage. Power dissipation can be minimized by providing an
external power source to V
source is always disabled.
Note: During start-up or when V
start-up circuit is capable of sourcing up to 20 mA. This may
lead to a high level of power dissipation in the IC (for a 48 V
input, approximately 1 W). Excessive start-up time caused
by external loading of the V
damage. Figure 4 gives the typical pre-regulator current at
start-up as a function of input voltage.
Si9102DN02-T1
PIN DESCRIPTION
*Pins 1, 4, 6, 13, 15, and 19 = N/C
ORDERING INFORMATION
Part Number
Si9102DN02
Si9102DJ02
(With Tape
Standard
and Reel)
DISCHARGE
SHUTDOWN
OSC OUT
Function
SOURCE
OSC IN
RESET
DRAIN
COMP
BIAS
+ V
V
- V
V
FB
REF
CC
IN
IN
Si9102DN02-T1-E3
Si9102DN02-E3
Si9102DJ02-E3
Lead (Pb)-free
Part Number
(With Tape
and Reel)
14-Pin DIP
CC
CC
10
11
12
13
14
7
8
1
2
3
4
5
6
9
such that the constant current
supply can result in device
CC
Vishay Siliconix
Temperature
- 40 to 85 °C
CC
drops below 9.4 V the
Pin
Range
exceeds the under-
20-Pin PLCC*
www.vishay.com
Si9102
10
11
12
14
16
17
18
20
2
3
5
7
8
9
Package
PLCC-20
PDIP-14
5