SI9121DY-3-T1 VISHAY [Vishay Siliconix], SI9121DY-3-T1 Datasheet - Page 3

• Manufacturer Part Number: SI9121DY-3-T1
• Description: High-Voltage, Non-Isolated Buck-Boost Converter for ISDN Digital Phones
• Manufacturer: VISHAY [Vishay Siliconix]

Notes
a.
b.
c.
d.
Document Number: 71112
S-40708—Rev. C, 19-Apr-04
SPECIFICATIONS
Supply
Supply Current
(Internally Regulater)
Supply Current
(External V
V
Start-Up Current
Thermal Shutdown
Thermal Shutdown Temperature
Thermal Hysteresis
Efficiency
Efficiency
Efficiency
DETAILED BLOCK DIAGRAM
OUT
BYPASS
Refer to PROCESS OPTION FLOWCHART for additional information.
Room = 25_C, Full = as determined by the operating temperature suffix.
The algebraic convention whereby the most negative value is a minimum and the most positive a maximum.
Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing.
V
V
supply Current
GND
V
NEG
OUT
CC
Parameter
CC
Applied)
5
6
7
3
2
R1*
R2*
+
−
a
(All Voltages Are With Respect To V
V
1.25 V
−
+
REF
GM
Symbol
I
8.5 V
START
T
T
Reference
I
I
GND
I
OUT
OTP
CC
HYS
Circuit
−
+
Bias/
+
−
Test Conditions (Internally Regulated)
Low Side
Error Amp
400 mA Output V
400-mA Output, V
Unless Otherwise Specified
V
3.5 V
1.5 V
CC
−
+
to V
V
0.6-V Hysteresis
NEG
NEG
0.6 V
0.67 V
V
GND to V
−
OUT
+
−
−
+
V
= −10 to −60 V
NEG
NEG
+10 V; V
CC
*R1 and R2 are internal voltage setting resistors used to set
output voltage to fixed 3.3 V or 5 V.
to V
= 0 V
= 48 V
= −48 V
NEG
NEG
−
+
+
−
NEG
p
PWM
OCL
>−20 V
H
L
NEG
Duty Cycle
50% Max.
+3.3 V
OSC
Unless Otherwise Specified)
+5 V
Soft Start
Hiccup Discharge Mode
V
CC
R
S
Temp
10 mA
Room
Room
Full
Full
Full
Full
Q
b
OTP
Min
c
Vishay Siliconix
−40 to 85_C
2 mA
Limits
Typ
170
1.2
1.5
0.2
25
77
73
5
d
−V
V
IN
NEG
Max
1.5
2.0
0.3
30
Si9121
www.vishay.com
4
8
1
c
CS
COMP
L
Unit
X
mA
_C
_C
%
%
3