OK zasilacz jest taki jak na początku postu czyli Codegen 300X 300W (nie pisałbym w tym poście o innym myślałem, że to logiczne ale sorrki). Siedzi tam tranzystor K2544, a układ scalony to AS2333F wygląda jak kontroler przetwornicy, (Dil 16), w pdf-ie widać na jego końcówkach napięcia odpowiadające napięciom zasilającym np. +3,3V; +5V; +12V Zasilacz na nowość nie wygląda, ale na forum nie spotkałem się jeszcze nigdzie z tym układzie scalonym AS2333F :arrow: alii Pytałem się o sprawdzenie zasilacza w poście Link Mam nadzieje, że będzie dla Ciebie stanowił pewną pomoc Ja sprawdzałem na H4 przez 5h (chodzi spoko przez kilka miesięcy i nie zapowiada się aby coś miało mu się stać), ale Tobie do tej bestii proponuje coś więcej niż jedną żarówkę 60W.Pozdrawiam
AS23xx Circuit
Secondary Side Housekeeping
SEMICONDUCTOR
Features
Description
o
Standard PC Power Good:
UV Detection on 4 rails
UV Detection of AC/Bulk supply
OV Detection on 4 rails
Open collector PG out
o
Programmable Fault output:
OV
OV plus UV
OV plus UV after start-up delay
o
OV Crow-Bar Driver
The AS23xx is a housekeeping circuit for monitoring the outputs of power
supplies. It directly senses all the output rails without the need for external dividers and detects undervoltage and overvoltage. It also provides an
additional undervoltage comparator which may be configured with any
arbitrary hysteresis to sense a divided down representation of the AC bulk
voltage. The housekeeping section provides all the features necessary to
allow external caps to set the common timing features of PC type power
supplies. In addition, negative rails may be sensed without the necessity
of a VEE connection, and negative sensing may be disabled without
affecting operation of the positive sense section. The 2.5 V series reference is available and can source up to 5 mA. This IC is available in 16
lead packages. Outputs include a POK (Power OK) and a fault signal.
o
Digital ON/OFF input
o
2.5 V Voltage Reference
o
Operates from 5 V or 12 V rail
The AS2333 includes sensing for ?12 V, 5 V, and 3.3 V. The AS2350
exchanges a -5 V sense capability for the 3.3 V input. The AS2316 monitors all supply voltages, but lacks CBD (Crow-Bar Driver).
Pin Configuration --
Top view
VCC
1
16
FAULT
VCC
1
16
CBD
+12V
2
15
VREF
+12V
2
15
FAULT
+5V
3
14
UVB
+5V
3
14
+3.3V
4
13
DELAY
+3.3V
4
-5V
5
12
POK
-12V
-12V
6
11
PGCAP
GND
7
10
AC
HYST
8
9
OFF
AS2316 SOIC
VCC
1
16 CBD
+12V
2
15 FAULT
VREF
+5V
3
14 VREF
13
UVB
+3.3V
4
13 UVB
5
12
DELAY
-12V
5
12 DELAY
GND
6
11
POK
GND
6
11 POK
HYST
7
10
PGCAP
HYST
7
10 PGCAP
OFF
8
9
AC
OFF
8
VCC
1
16
FAULT
+12V
2
15
+5V
3
+3.3V
AS2333 SOIC
VCC
1
16
CBD
VREF
+12V
2
15
FAULT
14
UVB
+5V
3
14
4
13
DELAY
+3.3V
4
-5V
5
12
POK
-12V
-12V
6
11
PGCAP
GND
7
10
HYST
8
9
9
AS2350 SOIC
AC
VCC
1
16 CBD
+12V
2
15 FAULT
VREF
+5V
3
14 VREF
13
UVB
-5V
4
13 UVB
5
12
DELAY
-12V
5
12 DELAY
GND
6
11
POK
GND
6
11 POK
AC
HYST
7
10
PGCAP
HYST
7
10 PGCAP
OFF
GND
8
9
AC
OFF
8
AS2316 PDIP
AS2333 PDIP
9
AC
AS2350 PDIP
Ordering Information
Model
Sense Voltage
Crow-Bar Driver
AS2316D, AS2316N
?12/?5/+3.3
No
AS2333D, AS2333N
?12/+5/+3.3
Yes
AS2350D, AS2350N
?12/?5
Yes
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95
AS23xx
Secondary Side Housekeeping Circuit
Functional Block Diagram
VREF
VCC
-
VCC
GND
nUV
UV
+
+12V
nRESET
-
+
nOV
OV
20 us
delay
-
+
+5V
nOV Latch
t
VCC
R
Latch
SQ
FAULT
nUV Latch
UV
R
Latch
QS
-
+
OV
nFAULT
VCC
CBD Latch powers up
in RESET state
SQ
Latch
R
-
+
+3.3V
UV
CBD
nRESET
-
500
nOV
OV
+
VCC
-
+
OV
1uA
nUV
Latch
nUV
+
-
+
-5V
-
+
-
Disable
+
VREF
+
OV
VCC
1uA
t
PGCAP
nPOK
20us delay
nUV
-
+
HYST
nOV
-
UV
VCC
VREF
-
-12V
AC
VCC
-
UV
UVB
VREF
VREF
+
-
Disable
+
-
VREF
POK
-
+
VREF
nAC WARNING
nFAULT
+
+
VCC
1uA
-
DELAY
HYST
VCC
OFF
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nRESET
nOFF WARNING
VREF
2.5V
96
+
- chip bias
VREF
Secondary Side Housekeeping Circuit
AS23xx
Pin Function Description (For AS2333/AS2350)
Pin Number Function
Description
1
VCC
Power input to the chip.
2
+12 V
Input for overvoltage and undervoltage for the +12 V rail.
3
+5 V
Input for overvoltage and undervoltage for the +5 V rail.
4
+3.3/-5 V
5
-12 V
Input for overvoltage and undervoltage for the +3.3 V rail or -5 V rail, depending on
product option.
Input for overvoltage and undervoltage for the -12 V rail. This function may be
disabled by tying this pin to a positive voltage above 2.4 V.
6
GND
Signal ground and silicon substrate.
7
HYST
Open collector output of the AC undervoltage comparator. A resistor between this pin
and AC will provide hysteresis to the AC undervoltage sensing.
8
OFF
Pulling this pin low will reset the FAULT latch and discharge the start-up timing
capacitors, UVB and PG CAP, allowing normal start-up for the system. Pulling this pin
high will send the FAULT signal high, prompting a system shutdown.
9
AC
Non-inverting input to the AC undervoltage sensing comparator. If the AC pin is
less than 2.5 V, POK goes low and UVB cap discharges.
10
PG CAP
A cap to ground provides a delay between undervoltage sensing becoming good
and the POK output going high. Cap discharges whenever an output or AC
undervoltage is detected.
11
POK
Open collector output of the undervoltage sensing comparators. This pin goes low
upon an undervoltage condition. Except for the delay set by the PG CAP, this pin
always reflects the actual state of the undervoltage sensing.
12
DELAY
13
UVB
14
15
VREF
FAULT
16
CBD
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A cap to ground will delay the FAULT signal when the OFF pin is used to shut down
the system. The POK will signal a power fail warning immediately, but the FAULT
shutdown of the power supply will be delayed.
A cap to ground provides start-up blanking of the undervoltage sensing portion of the
FAULT signal. This pin may also be grounded to prevent undervoltage conditions from
triggering the FAULT signal. This pin discharges the cap whenever AC goes low or
FAULT pin goes high.
2.5 V Voltage reference. This is a series regulator type reference.
Open collector output of the overvoltage and undervoltage comparators.
Crow-bar drive output of the overvoltage faults only.
97
AS23xx
Secondary Side Housekeeping Circuit
Pin Function Description (For AS2316)
Pin Number Function
1
Description
2
VCC
+12 V
Power input to the chip.
Input for overvoltage and undervoltage for the +12 V rail.
3
+5 V
Input for overvoltage and undervoltage for the +5 V rail.
4
+3.3
Input for overvoltage and undervoltage for the +3.3 V rail.
5
-5 V
Input for overvoltage and undervoltage for the -5 V rail.
6
-12 V
Input for overvoltage and undervoltage for the -12 V rail. This function may be
disabled by tying this pin to a positive voltage above 2.4 V.
7
GND
Signal ground and silicon substrate.
8
HYST
Open collector output of the AC undervoltage comparator. A resistor between this pin
and AC will provide hysteresis to the AC undervoltage sensing.
9
OFF
Pulling this pin low will reset the FAULT latch and discharge the start-up timing
capacitors, UVB and PG CAP, allowing normal start-up for the system. Pulling this pin
high will send the FAULT signal high, prompting a system shutdown.
10
AC
Non-inverting input to the AC undervoltage sensing comparator. If the AC pin is
less than 2.5 V, POK goes low and UVB cap discharges.
11
PG CAP
A cap to ground provides a delay between undervoltage sensing becoming good
and the POK output going high. Cap discharges whenever an output or AC
undervoltage is detected.
12
POK
Open collector output of the undervoltage sensing comparators. This pin goes low
upon an undervoltage condition. Except for the delay set by the PG CAP, this pin
always reflects the actual state of the undervoltage sensing.
13
DELAY
14
UVB
15
VREF
FAULT
16
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A cap to ground will delay the FAULT signal when the OFF pin is used to shut down
the system. The POK will signal a power fail warning immediately, but the FAULT
shutdown of the power supply will be delayed.
A cap to ground provides start-up blanking of the undervoltage sensing portion of the
FAULT signal. This pin may also be grounded to prevent undervoltage conditions from
triggering the FAULT signal. This pin discharges the cap whenever AC goes low or
FAULT pin goes high.
2.5 V Voltage reference. This is a series regulator type reference.
Open collector output of the overvoltage and undervoltage comparators.
98
Secondary Side Housekeeping Circuit
AS23xx
Absolute Maximum Ratings
Parameter
Symbol
Continuous Power Dissipation at 25°C
Junction Temperature
Unit
VCC
PD
Supply Voltage
Rating
20
V
1000
mW
150
°C
0 to 105
°C
TJ
?
Operating Temperature Range
Storage Temperature Range
TSTG
TL
Lead Temperature, Soldering 10 Seconds
-65 to 150
°C
300
°C
Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a
stress rating only and functional operation of the device at these or any other conditions above indicated in the operational sections
of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Recommended Conditions
Parameter
Typical Thermal Resistance
?JA
?JC
Symbol
Rating
Unit
Package
VCC
5 - 12
V
16L SOIC
65°C/W
45°C/W
10.0 mW/°C
16L PDIP
80°C/W
35°C/W
12.5 mW/°C
Supply Voltage
Typical Derating
Electrical Characteristics
Electrical Characteristics are guaranteed over full junction temperature range (0 to 105°C). Ambient temperature must be derated
based on power dissipation and package thermal characteristics. Unless otherwise specified, the conditions of test are VCC = 12
V; +3.3 V = 3.3 V; +5 V = 5 V; +12 V = 12 V; -12 V = -12 V; -5 V = -5 V; OFF = low.
Parameter
Symbol
Test Condition
ICC
VCC Min.
Min.
no faults
Typ.
Max.
Unit
Bias
Supply Current
Min. VCC for operation
8
12
mA
4.2
VREF = 2.5 V, no faults
V
Undervoltage, Overvoltage
+3.3 V (Not available on AS2350)
+3.3 V Undervoltage
UV
2.87
2.95
3.03
V
+3.3 V Overvoltage
OV
3.76
3.86
3.96
V
+3.3 V Input Current
IB
-0.1
0
0.1
mA
V+3.3 = +3.3 V, V+5 = +5.0 V
+5 V
+5 V Undervoltage
UV
4.40
4.50
4.60
V
+5 V Overvoltage
OV
5.74
5.89
6.04
V
+5 V Input Current
IB
1.6
2.5
mA
V+5 = +5.0 V, V+3.3 = +3.3 V
+12 V
+12 V Undervoltage
UV
10.25
10.50
10.60
V
+12 V Overvoltage
OV
14.53
14.90
15.27
V
+12 V Input Current
IB
0.8
1.5
mA
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V+12 = +12.0 V
99
AS23xx
Secondary Side Housekeeping Circuit
Electrical Characteristics
(cont'd)
Electrical Characteristics are guaranteed over full junction temperature range (0 to 105°C). Ambient temperature must be derated
based on power dissipation and package thermal characteristics. Unless otherwise specified, the conditions of test are VCC = 12
V; +3.3 V = 3.3 V; +5 V = 5 V; +12 V = 12 V; -12 V = -12 V; -5 V = -5 V.
Parameter
Symbol
Test Condition
Min.
Typ.
Max.
Unit
-5 V (Not available on AS2333)
-5 V Undervoltage
UV
-3.80
-4.00
-4.20
V
-5 V Overvoltage
OV
-6.00
-6.25
-6.55
V
-5 V Input Current
IB
VD
-80
-150
uA
2.3
2.4
V
-9.20
-9.55
-9.80
V
-14.55
-15.04
-15.60
V
-100
-200
uA
2.0
2.2
V
2.520
2.540
V
-0.5
-1
uA
0.01
1
-5 V Disable Voltage
V-5 = -5.0 V
Minimum voltage to disable
-12 V
-12 V Undervoltage
UV
-12 V Overvoltage
OV
-12 V Input Current
IB
VD
Minimum voltage to disable
AC Undervoltage
UV
TJ = 25°C
AC Input Current
HYST High State Leakage
IB
IL
VHYST = 5 V; AC & gt; 2.5 V
HYST Output Current
IOL
VHYST = 0.3 V; AC & lt; 2.5 V
HYST Low Voltage
VOL
IHYST = 1 mA; AC & lt; 2.5 V
IL
IOL
VPOK = 12 V; no faults
-12 V Disable Voltage
V-12 = -12.0 V
AC/HYST
2.460
1
3
uA
mA
0.3
V
Outputs
POK High State Leakage
POK Output Current
FAULT High State Leakage
FAULT Output Current
IL
VOL
VPOK = 0.4 V; VCC = 7 V undervoltage
condition
100
5
VFAULT = 12 V; OFF = High
200
10
0.01
uA
mA
1
uA
VFAULT = 0.4 V; no faults
VCC = 12 V
VCC = 5 V
3
1.3
10
4
mA
mA
mA
CBD (Crow-Bar Drive)
Minimum Output Current
IOH
overvoltage condition
-25
-35
CBD Output High Voltage
VOH
ICBD = 0 mA; T = 25°C
ICBD = 0 mA; T = 105°C; overvoltage
condition
2.0
1.4
2.5
3.0
3.3
V
V
CBD Pulldown Resistance
ROUT
ICBD = 1 mA; no faults
300
500
1000
1000
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100
Secondary Side Housekeeping Circuit
Electrical Characteristics
AS23xx
(cont'd)
Electrical Characteristics are guaranteed over full junction temperature range (0 to 105°C). Ambient temperature must be derated
based on power dissipation and package thermal characteristics. Unless otherwise specified, the conditions of test are VCC = 12
V; +3.3 V = 3.3 V; +5 V = 5 V; +12 V = 12 V; -12 V = -12 V; -5 V = -5 V.
Parameter
Symbol
Test Condition
Min.
Typ.
Max.
Unit
VREF
?VREF
IREF = 0 mA, TJ = 25°C
VCC = 5 V to 15 V
2.488
2.500
2.525
V
Line Regulation
10
15
mV
Load Regulation
?VREF
Temperature Deviation*
?VREF
IREF = 0 V to -5 mA
0 & lt; TJ & lt; 105°C
Voltage Reference
Output Voltage
10
15
mV
10
15
mV
uA
Start-Up Functions
UVB Pull-up Current Source
UVB Clamp
IOH
VOH MAX
VUVB = 2.0 V; no faults
-0.4
-1
-1.9
3.3
3.1
IUVB
IUVB = 10 uA; no faults
VUVB = 2.0 V; FAULT = low;
AC & lt; 2.5 V
2.9
UVB Discharge Current
(AC shutdown)
3
8
mA
UVB Discharge Current
(FAULT shutdown)
IOL
VUVB = 2.0 V; FAULT = high;
AC & gt; 2.5 V
2.5
10
mA
UVB Low Output Voltage
VOL
IUVB = 100 uA;
FAULT = low; AC & lt; 2.5 V
PG CAP Pull-up Current Source
VPGCAP = 2.0 V; no faults
-0.5
PG CAP Clamp
IOH
VOH MAX
PG CAP Discharge Current
IOL
IPGCAP = 10 uA; no faults; AC & gt; 2.5 V
VPGCAP = 2.0 V; undervoltage
condition
PG CAP Low Output Voltage
VOL
OFF Input Low Voltage
VIH
VIL
OFF Pull-up to VCC
R
VOFF = 0 V
DELAY Pull-up Current Source
IOH
VOH MAX
IOL
VDELAY = 0 V; OFF = high
IDELAY = 10 uA; OFF = high
VDELAY = 2.0 V; OFF = low
0.2
V
-1
-1.4
uA
2.9
3.1
3.3
2
6
IPGCAP = 100 uA; undervoltage
condition
OFF Input High Voltage
DELAY Clamp
DELAY Discharge Current
V
V
mA
0.2
2.0
V
V
0.8
V
50
100
kOhm
-0.5
-1
-2.0
uA
2.9
3.1
3.3
V
2.5
10
25
DELAY Low Output Voltage
mA
VOL
IDELAY = 100 uA; OFF = low
0.2
V
*Temperature deviation is defined as the maximum deviation of the reference over the given temperature range and does not imply
an incremental deviation at any given temperature.
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101
AS23xx
Secondary Side Housekeeping Circuit
Theory of Operation
just one or the other output is used depending on
the PSU's cost and system definition. Both
methods are intended to protect the customer's
system, and the customer, as the first priority.
The AS23xx performs housekeeping functions for
power supplies, especially switching power supplies for personal computers. The chip resides on
the secondary side of the power supply (PSU),
and it performs three primary functions:
1) monitors the output voltages and reports
faults
2) sequences the start-up of the PSU
3) sequences the shutdown of the PSU
Section 1 - Output Voltages and Faults
1.0 Output Voltage Monitoring
The AS23xx monitors the standard voltage outputs for PC type power supplies. It has inputs for
+12 V, +5 V, +3.3 V, -5 V and -12 V. These
inputs are tied directly to the outputs of the PSU,
and therefore do not require external dividers to
set the error thresholds. These pins are monitored for both overvoltage (OV) and undervoltage
(UV) conditions. The specs for these thresholds
are listed in the data sheet.
1.1 Overvoltage Faults: FAULT and CBD
An overvoltage condition in a power supply is
considered to be a catastrophic and dangerous
condition which must result in a safe, complete
and near-instantaneous shutdown of the system.
Overvoltages most often result from a break in
the system feedback and control circuitry or from
a short between outputs. When the AS23xx
detects an overvoltage, the fault is latched internally, and the FAULT and CBD pins go high. The
FAULT pin is an open collector NPN output which
is intended to drive an optocoupler LED for feedback to the primary side controller of the PSU.
The CBD pin is an NPN Darlington output which
is intended to drive an SCR crowbar circuit which
will short circuit the outputs of the PSU. Usually,
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1.2 Undervoltage Faults: POK and
FAULT
An undervoltage condition is sometimes not considered a catastrophic or dangerous condition,
but always one which the customer should be
warned about. The POK signal is a logic line to
the customer's system that is specified in most
PC type power supply systems. The AS23xx will
pull the POK signal low when a UV fault is detected. A UV fault may or may not require the system
to shut down, so an undervoltage blanking pin is
provided (UVB). Grounding this pin will prevent
UV faults from propagating to the FAULT pin.
CBD does not react to UV faults.
1.3 Input Undervoltage: AC and HYST
In addition, there is a special undervoltage detection input for sensing the input voltage to the
power supply, designated as the AC pin. This pin
will cause the POK pin to go low if there is insufficient voltage to run the PSU outputs. Since
power supplies must maintain high voltage isolation between the primary and secondary sides of
the system, the AC pin is usually tied to a divided
down and filtered representation of the secondary side switching waveform. Hysteresis for this
function, to provide immunity from line ripple, is
configured by the PSU designer and is implemented with the HYST pin, which is an open collector output of the AC comparator.
Section 2 - PSU Start-up Sequences
2.0 System Start-up Sequence
When the power supply starts up, the AS23xx
must not erroneously report a FAULT. In addition,
most PC type power supply specifications require
102
Secondary Side Housekeeping Circuit
AS23xx
a specific timing sequence for the POK signal.
Some PSU systems also require an isolated, low
voltage, low power remote turn-on switch, rather
than a large line cord switch.
0.4 V if the VCC of the AS23xx is tied to the 12 V
output or an auxiliary rail.
2.1 VREF Enable of Chip Bias
Since the VCC of the AS23xx comes up in a finite
amount of time, and since the VREF of the chip
and the bias for the comparators are not within
specification until approximately 4.2 V of VCC is
available, the comparators for OV and UV and
most other functions are disabled until VREF is
within spec. This prevents the false detection of a
FAULT due to an erroneous VREF. Similarly, if
VREF is too heavily loaded and gets pulled low
out of spec, these functions will also shut off.
2.2 Blanking UV's During Start-up:
UVB
As the power supply outputs come up, the undervoltage FAULTs must be blanked to allow the
supply to complete its start-up. Putting a capacitor to ground on the UVB pin will allow the PSU
designer to set a specific period of time during
which undervoltages will not propagate to the
FAULT pin. The UVB pin provides a 1 uA current
source to charge the cap, and once the UVB pin
charges above 2.5 V, the undervoltage sensing is
enabled. UVB does not blank undervoltages to
the POK pin. The UVB pin is clamped one diode
above VREF, or about 3.1 V, allowing fast discharge of the capacitor when the system resets.
2.3 POK Bias
The POK pin has some specific requirements
based on industry standard PC power supply
specifications. At start-up, the POK pin must not
rise above 0.4 V. The POK pin is an NPN open
collector whose base is tied to VCC via a simple
resistor. Therefore, once VCC pulls above one
diode or about 0.6 V, the POK pin will go low and
saturate. If the POK pin external pull-up is to the
5 V output, the POK signal will not go above
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2.4 POK Start-up Timing: PGCAP
In addition to 2.3 above, most PC power supplies
require the POK pin to remain low until all outputs
have been good for at least 100 ms but not more
than 500 ms. A cap to ground on the PGCAP pin
allows the PSU designer to set the timing delay
between the PSU outputs becoming good and
the POK pin going high. The PGCAP pin provides a 1 uA current source to charge the cap,
and when the cap charges above 2.5 V, the POK
pin goes high. When an undervoltage occurs, the
PGCAP pin discharges rapidly and the POK pin
goes low. The POK pin does not respond to
overvoltages.
2.5 Isolated Remote On/Off Switching:
OFF and FAULT
A low voltage, isolated remote on/off switch may
be implemented with the AS23xx OFF pin. If the
chip VCC is run off an auxiliary rail, the FAULT
signal may be used to start and stop the PSU.
When the OFF pin is pulled from high to low or
grounded, the FAULT pin resets to a low state,
which may be used to drive an optocoupler to
enable the primary side PWM controller. Allowing
the OFF pin to go open circuit or high causes the
POK pin to go low immediately, and the FAULT
pin will go high after a time delay set by a cap to
ground on the DELAY pin. This allows the customer's system to receive a POK warning before
the PSU actually shuts down.
Section 3 - PSU Shutdown Sequences
3.0 Shutdown Sequence
For normal shutdowns, the primary requirement
is that the POK signal should go low some minimum time before the PSU outputs fall out of
spec.
103
AS23xx
Secondary Side Housekeeping Circuit
3.1 Delaying Remote OFF: DELAY
3.2 AC Warning Prior to Primary
Drop-out
In systems which use the OFF and FAULT pins to
provide remote on/off switching, the delay
between the OFF pin going high and the FAULT
signal going high is programmable with a capacitor to ground on the DELAY pin as described in
2.5 above. The POK pin, on the other hand will
go high immediately after the OFF pin is open circuited or pulled high, giving the system warning
of the impending shutdown. The DELAY pin provides a 1 uA current source to charge the cap,
and when the cap charges above 2.5 V, the
FAULT pin will go high.
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In systems where the input line voltage is
switched, the AC pin threshold should be set so
that it causes POK to go low before the primary
bulk voltage reaches drop-out and the primary
PWM shuts off. The output of the AC comparator
also causes the UVB pin to pull low, so that the
undervoltage sensing does not trip the FAULT
latch as the outputs fall below spec. Recall that
the AC pin senses a divided down and filtered
representation of the secondary side switching
waveform, which will provide a proportional representation of the primary voltage via the turns
ratio of the transformer.
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