KA3505 Fairchild Semiconductor, KA3505 Datasheet - Page 4

• Manufacturer Part Number: KA3505
• Description: IC POWER SUPPLY SUPERVISOR 16DIP
• Manufacturer: Fairchild Semiconductor

Specifications of KA3505

• Applications: Power Supply, Supervisor
• Voltage - Supply: 15 V ~ 30 V
• Current - Supply: 5mA
• Operating Temperature: -25°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 16-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Input: -

KA3505
Pin Definitions
4
Pin No.
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
T
T
Name
PSON
PGO
GND
FPO
IS12
IS33
V
PSON
T
PROT
V33
V12
PGI
IS5
V5
RI
PG
CC
Over and Under Voltage Protection Input for the 3.3V. It directly senses the 3.3V
rail without any external divider.
Over and Under Voltage Protection Input for the 5V. It directly senses the 5V rail
without any external divider.
Over and Under Voltage Protection Input for the 12V. It directly senses the 12V
rail without any external divider.
Power Good Signal Generator Input. It should be supplied from a bulk
dependent voltage in order to detect power on and off state.
Supply voltage. Its recommended operating voltage is ranged from 15V to 30V.
Fault Protection Output (Open Collector Output). This pin indicates the fault
condition. When fault state occurs, the PGO signal goes Low.
Normal = ’Low", Fault = "High".
Remote on/off input. It does TTL operation and its threshold voltage is 1.4V. In
case of open circuit, the voltage at this pin is High (5.0V). If PSON = "Low", then
FPO = "Low". It means the main SMPS is working. When PSON = "High or
Open", then FPO = "High" and the main SMPS stops to work.
Timing pin for PSON delay. Ton/Toff=8ms/24ms (Typ.) with Cpson=0.1 F
externally. PSON On Delay Time (Ton) is measured as PSON input goes Low to
High. PSON Off Delay Time (Toff) can be measured reversely.
Power Good Output Signal (Open Collector).
PGO = "High" means "Power Good" for operation and PGO = "Low" means
"Power Fail".
Timing pin for PGO delay. TPG = 270ms (Typ.) with CPG = 2.2 F externally. The
high/low threshold voltages are 1.8V/0.6V and the voltage of pin10 would be
charged up to 2.9V for noise margin.
OCP current sense setting pin. The reference voltage at this pin is set to 1.25V
internally.You can fix the OCP reference current by using RI resistor.
Ground
Timing pin for under voltage protection and over current protection blank-out
time. Its threshold voltage is 1.8V and clamped at 2.9V after full charging. Target
of delay time is 38ms and it is realized through external capacitor (C=0.47 F).
Current sense input for +12V. This pin is connected to the current sensing
resistor or inductor. You can define OCP offset voltage for +12V by using RI
resistor externally. If you connected RI resistor of 62k at Pin11 to ground, the
reference current(Iref) should be 20 A. After that, you can make a constant OCP
offset voltage (V
In case the voltage drop (=I
than offset voltage, FPO becomes "High" after some delay time and the main
SMPS is turned-off. So the over current level is determined by following
equation. (I
Current sense input for +5V. You can make the +5V OCP function as previous
method in IS12 (Pin14).
Current sense input for +3.3V. You can also make the +3.3V OCP function as
previous method in IS12 (Pin14).
See application note for details.
O.12
OFFSET
= V
OFFSET
= R
Pin Function Description
O
/ R
O
.
12
S
)
5
R
S
Iref).
) of the sense resistor or inductor is larger