LINER LTC1536I Precision triple supply monitor for pci application Datasheet

LTC1536
Precision Triple Supply Monitor
for PCI Applications
U
FEATURES
■
■
■
■
■
■
■
■
■
■
■
DESCRIPTIO
Simultaneously Monitors 5V, 3.3V and
Adjustable Inputs
Guaranteed Threshold Accuracy: ±0.75%
Low Supply Current: 100µA
Internal Reset Time Delay: 200ms
Manual Pushbutton Reset Input
Active Low and Active High Reset Outputs
Active Low “Soft” Reset Output
Power Supply Glitch Immunity
Guaranteed Reset for Either VCC3 ≥ 1V or VCC5 ≥ 1V
Meets PCI tFAIL Timing Specifications Rev 2.1
8-Pin SO and MSOP Packages
U
APPLICATIO S
■
■
■
■
■
For 3.3V and 5V supplies that are > 500mV below spec or
for the condition when the 5V supply falls below the 3.3V
supply, the LTC1536 has a very fast response time capable
of meeting the PCI tFAIL timing specification. Tight 0.75%
threshold accuracy and glitch immunity ensure reliable
reset operation without false triggering.
The RST output is guaranteed to be in the correct state for
VCC5 or VCC3 down to 1V. The 100µA typical supply current
makes the LTC1536 ideal for power-conscious systems.
A manual pushbutton reset input provides the ability to
generate a very narrow “soft” reset pulse (100µs typ) or a
200ms reset pulse equivalent to a power-on reset. Both
SRST and RST outputs are open-drain and can be OR-tied
with other reset sources.
PCI-Based Systems
Desktop Computers
Notebook Computers
Intelligent Instruments
Portable Battery-Powered Equipment
Network Servers
, LTC and LT are registered trademarks of Linear Technology Corporation.
U
■
The LTC®1536 is designed for PCI local bus applications
with multiple supply voltages that require low power,
small size, high speed and high accuracy supply
monitoring.
TYPICAL APPLICATIO
Power Fail Waveform
5V Dropping Below 3.3V by 300mV
Motherboard PCI RST Generation
0.1µF
LTC1536
1
2
5V ± 5%
0.1µF
PUSHBUTTON
RESET
3
4
VCC3
PBR
VCC5
SRST
VCCA
RST
GND
RST
RPU
7
6
5
RST
VCC5 = 5V TO 3V STEP
VCC3 = VCCA = 3.3V
4.7k PULL-UP FROM
RST TO VCC3
5
8
PCI
LOCAL
BUS
PWR GOOD
VOLTAGE (1V/DIV)
3.3V ± 0.3V
4
VCC5
3
2
RST
1
RPU SELECTED TO MEET RISE TIME
SLEW RATE REQUIREMENTS (1k MIN)
1536 TA01
0
TIME (20ns/DIV)
1536 TA02
1
LTC1536
W W
W
AXI U
U
ABSOLUTE
RATI GS
(Notes 1, 2)
Terminal Voltage
VCC3, VCC5, VCCA .................................... – 0.3V to 7V
RST, SRST ............................................ – 0.3V to 7V
RST ......................................... – 0.3V to VCC3 + 0.3V
PBR .......................................................... – 7V to 7V
Operating Temperature Range
LTC1536C .............................................. 0°C to 70°C
LTC1536I ............................................ – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
W
U
U
PACKAGE/ORDER I FOR ATIO
ORDER
PART NUMBER
TOP VIEW
VCC3
VCC5
VCCA
GND
8
7
6
5
1
2
3
4
PBR
SRST
RST
RST
MS8 PACKAGE
8-LEAD PLASTIC MSOP
LTC1536CMS8
VCC3 1
8 PBR
VCC5 2
7 SRST
VCCA 3
6 RST
GND 4
5 RST
MS8 PART MARKING
TJMAX = 125°C, θJA = 160°C/ W
ORDER
PART NUMBER
TOP VIEW
LTBV
LTC1536CS8
LTC1536IS8
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
1536
1536I
TJMAX = 125°C, θJA = 150°C/ W
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
VCC3 = 3.3V, VCC5 = 5V, VCCA = VCC3, TA = 25°C unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
VRT3
Reset Threshold VCC3
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
2.962
2.925
2.985
2.985
3.000
3.008
V
V
VRT5
Reset Threshold VCC5
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
4.687
4.625
4.725
4.725
4.750
4.762
V
V
VRTA
Reset Threshold VCCA
0°C ≤ TA ≤ 70°C
– 40°C ≤ TA ≤ 85°C
●
●
0.992
0.980
1.000
1.000
1.007
1.007
V
V
VCC
VCC3 or VCC5 Operating Voltage
RST in Correct Logic State
●
1
7
V
IVCC3
VCC3 Supply Current
PBR = VCC3
●
100
200
µA
IVCC5
VCC5 Input Current
VCC5 = 5V
●
10
20
µA
IVCCA
VCCA Input Current
VCCA = 1V, 0°C ≤ TA ≤ 70°C
VCCA = 1V, – 40°C ≤ TA ≤ 85°C
●
●
–5
– 15
0
0
5
15
nA
nA
tRST
Reset Pulse Width
RST Low with 10kΩ Pull-Up to VCC3
0°C to 70°C
– 40°C to 85°C
●
●
140
140
200
200
280
300
ms
ms
●
50
100
200
µs
tSRST
Soft Reset Pulse Width
SRST Low with 10kΩ Pull-Up to VCC3
tUV
VCC Undervoltage Detect to RST
VCC5, VCC3 or VCCA Less Than Reset
Threshold VRT by 1%
2
13
µs
LTC1536
ELECTRICAL CHARACTERISTICS
VCC3 = 3.3V, VCC5 = 5V, VCCA = VCC3, TA = 25°C unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
IPBR
PBR Pull-Up Current
PBR = 0V, 0°C ≤ TA ≤ 70°C
PBR = 0V, – 40°C ≤ TA ≤ 85°C
VIL
PBR, RST Input Low Voltage
●
VIH
PBR, RST Input High Voltage
●
2
V
tPW
PBR Min Pulse Width
●
40
ns
tDB
PBR Debounce
Deassertion of PBR Input to SRST
Output (PBR Pulse Width = 1µs)
●
tPB
PBR Assertion Time for Transition
from Soft to Hard Reset Mode
PBR Held Less Than VIL, 0°C to 70°C
PBR Held Less Than VIL, – 40°C to 85°C
●
●
VOL
RST Output Voltage Low
ISINK = 5mA
●
●
MIN
TYP
MAX
3
3
7
7
10
15
0.8
1.4
1.4
UNITS
µA
µA
V
20
35
ms
2.0
2.0
2.8
3.0
s
s
●
0.15
0.4
V
ISINK = 100µA
0°C ≤ TA ≤ 70°C
VCC3 = 1V, VCC5 = 0V
VCC3 = 0V, VCC5 = 1V
VCC3 = 1V, VCC5 = 1V
●
●
●
0.05
0.05
0.05
0.4
0.4
0.4
V
V
V
ISINK = 100µA
– 40°C ≤ TA ≤ 85°C
VCC3 = 1.1V, VCC5 = 0V
VCC3 = 0V, VCC5 = 1.1V
VCC3 = 1.1V, VCC5 = 1.1V
●
●
●
0.05
0.05
0.05
0.4
0.4
0.4
V
V
V
SRST Output Voltage Low
ISINK = 2.5mA
●
0.15
0.4
V
RST Output Voltage Low
ISINK = 2.5mA
●
0.15
0.4
V
RST Output Voltage High (Note 3)
ISOURCE = 1µA
●
VCC3 – 1
V
SRST Output Voltage High (Note 3)
ISOURCE = 1µA
●
VCC3 – 1
V
RST Output Voltage High
ISOURCE = 600µA
●
VCC3 – 1
V
tPHL
Propagation Delay RST to RST
High Input to Low Output
CRST = 20pF
25
ns
tPLH
Propagation Delay RST to RST
Low Input to High Output
CRST = 20pF
45
ns
tFAIL
VCC5 or VCC3 0.5V Undervoltage
to RST (Note 4)
VCC5 Drops Below 4.25V or VCC3 Drops
Below 2.5V (Note 5)
●
150
450
ns
tPF
VCC5 < (VCC3 – 300mV) RST (Note 4)
VCC5 Drops Below VCC3 By 300mV
(Note 6)
●
50
90
ns
VOH
The ● denotes specifications which apply over the full operating
temperature range.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: All voltage values are with respect to GND.
Note 3: The output pins SRST and RST have weak internal pull-ups to
VCC3 of 6µA. However, external pull-up resistors may be used when faster
rise times are required.
Note 4: Conforms to PCI Local Bus Specification Rev 2.1,
Sect. 4.3.2 for tFAIL.
Note 5: VCC3 or VCC5 falling at – 0.1V/µs, time measured from
VRTX – 500mV to RST at 1.5V.
Note 6: VCC5 falling from 5V to 3V in ≤10ns, time measured from
VCC5 = (VCC3 – 300mV) to RST at 1.5V.
3
LTC1536
U W
TYPICAL PERFORMANCE CHARACTERISTICS
IVCC3 vs Temperature
140
20.0
120
17.5
3
60
40
INPUT CURRENT (nA)
IVCC5 (µA)
80
12.5
10.0
7.5
5.0
20
– 25
35
15
–5
55
TEMPERATURE (°C)
0
– 45
75
– 25
35
15
–5
55
TEMPERATURE (°C)
–1
1536 G03
1536 G02
VCC5 Threshold Voltage
vs Temperature
VCC3 Threshold Voltage
vs Temperature
VCCA Threshold Voltage
vs Temperature
3.010
1.005
4.745
3.005
1.004
4.740
4.735
4.730
4.725
4.720
4.715
4.710
4.705
4.700
– 60 – 40 – 20 0 20 40 60
TEMPERATURE (°C)
80
VCCA THRESHOLD VOLTAGE, VRTA (V)
4.750
VCC3 THRESHOLD VOLTAGE, VRT3 (V)
VCC5 THRESHOLD VOLTAGE, VRT5 (V)
0
–3
0.8 0.85 0.9 0.95 1.0 1.05 1.1 1.15 1.2
INPUT VOLTAGE (V)
75
1536 G01
3.000
2.995
2.990
2.985
2.980
2.975
2.970
2.965
2.960
– 60 – 40 – 20
100
0
20
40
60
80
0.999
0.998
0.997
0.996
215
210
205
200
195
75
100
1536 G07
80
110.0
107.5
105.0
102.5
100.0
97.5
95.0
– 50
– 25
50
25
0
TEMPERATURE (°C)
100
1536 G06
PBR ASSERTION TIME TO RESET, tPB (SEC)
SOFT RESET PULSE WIDTH, tSRST (µs)
220
4
1.000
PBR Assertion Time to Reset
vs Temperature
112.5
50
25
0
TEMPERATURE (°C)
1.001
“Soft” Reset Pulse Width
vs Temperature
225
– 25
1.002
1536 G05
Reset Pulse Width
vs Temperature
190
– 50
1.003
0.995
– 60 – 40 – 20 0 20 40 60
TEMPERATURE (°C)
100
TEMPERATURE (°C)
1536 G04
RESET PULSE WIDTH, tRST (ms)
1
–2
2.5
0
– 45
TA = 25°C
2
15.0
100
IVCC3 (µA)
VCCA Input Current
vs Input Voltage
IVCC5 vs Temperature
75
100
1536 G08
2.25
2.20
2.15
2.10
2.05
2.00
1.95
1.90
– 50
– 25
50
25
0
TEMPERATURE (°C)
75
100
1536 G09
LTC1536
U W
TYPICAL PERFORMANCE CHARACTERISTICS
VCC3 Typical Transient Duration
vs Reset Comparator Overdrive
VCC5 Typical Transient Duration
vs Reset Comparator Overdrive
45
35
30
25
20
15
10
5
0
0.001
0.01
0.1
1
VCC3 RESET COMPARATOR OVERDRIVE, VRT3 – VCC3 (V)
35
30
25
20
15
10
5
0
0.01
0.1
1
0.001
VCC5 RESET COMPARATOR OVERDRIVE, VRT5 – VCC5 (V)
1536 G10
RESET OCCURS
ABOVE CURVE
35
30
25
20
15
10
5
0
0.01
0.1
1
0.001
VCCA RESET COMPARATOR OVERDRIVE, VRTA – VCCA (V)
1536 G11
RST Output Voltage
vs Supply Voltage
1536 G12
RST Output Voltage
vs Supply Voltage
5.0
5.0
VCC5 = VCC3 = VCCA
4.7k PULL-UP FROM RST TO VCC5
TA = 25°C
4.0
VCC5 = VCC3 = VCCA
RST PIN LOADED WITH
10MΩ TO GND
TA = 25°C
4.5
RST OUTPUT VOLTAGE (V)
4.5
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
TYPICAL TRANSIENT DURATION (µs)
40
40
RESET OCCURS
ABOVE CURVE
40
TYPICAL TRANSIENT DURATION (µs)
RESET OCCURS
ABOVE CURVE
45
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE, VCC (V)
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE, VCC (V)
1536 G13
1536 G16
Power-Fail Response Time
vs Temperature
Undervoltage Response Time
vs Temperature
DEVICE THRESHOLD
PCI SPEC
VCC3
VOLTAGE (1V/DIV)
VOLTAGE (500mV/DIV)
RST OUTPUT VOLTAGE (V)
TYPICAL TRANSIENT DURATION (µs)
50
VCCA Typical Transient Duration
vs Reset Comparator Overdrive
85° – 40°
25°
tFAIL SPEC
MARGIN
VCC3 FALLING
FROM 3.3V TO
2.3V AT (– 0.1V/µs)
VCC5
85°
– 40°
25°
RST
RST
TIME (1µs/DIV)
TIME (20ns/DIV)
1536 G15
1536 G14
5
LTC1536
U
U
U
PIN FUNCTIONS
VCC3 (Pin 1): 3.3V Sense Input and Power Supply Pin for
the IC. Bypass to ground with ≥ 0.1µF ceramic capacitor.
VCC5 (Pin 2): 5V Sense Input. Used as gate drive for RST
output FET when the voltage on VCC5 is greater than the
voltage on VCC3.
VCCA (Pin 3): 1V Sense, High Impedance Input. Can be
used as a logic input with a 1V threshold. If unused it can
be tied to either VCC3 or VCC5.
GND (Pin 4): Ground.
RST (Pin 5): Reset Logic Output. Active high CMOS logic
output, drives high to VCC3, buffered compliment of RST.
An external pull-down on the RST pin will drive this pin high.
RST (Pin 6): Reset Logic Output. Active low, open-drain
logic output with weak pull-up to VCC3. Can be pulled up
greater than V CC3 when interfacing to 5V logic.
Asserted when one or more of the supplies are below trip
thresholds and held for 200ms after all supplies become
valid. Also asserted after PBR is held low for more than two
seconds and for an additional 200ms after PBR is released.
SRST (Pin 7): “Soft” Reset. Active low, open-drain logic
output with weak pull-up to VCC3. Can be pulled up greater
than VCC3 when interfacing to 5V logic. Asserted for 100µs
after PBR is held low for less than two seconds and released.
PBR (Pin 8): Pushbutton Reset. Active low logic input with
weak pull-up to VCC3. Can be pulled up greater than VCC3
when interfacing to 5V logic. When asserted for less than
two seconds, outputs a soft reset 100µs pulse on the SRST
pin. When PBR is asserted for greater than two seconds,
the RST output is forced low and remains low until 200ms
after PBR is released.
W
BLOCK DIAGRAM
VCC3
VCC3
7µA
PBR 8
TO POWER DETECT
AND VCC INTERNAL
VCC3 1
6µA
SOFT RESET
PBR
TIMER
RESET
7
SRST
6
RST
5
RST
–
FAST
+
–
VCC3
SLOW
+
VCC3
6µA
+
FAST
–
200ms
RESET
GENERATOR
POWER
DETECT/
GATE DRIVE
VCC3
–
VCC5 2
VCC5
FAST
TO
POWER
DETECT
+
–
SLOW
+
VCCA 3
–
SLOW
+
GND 4
REF
1326 BD
6
LTC1536
WU
W
TI I G DIAGRA S
VCC Monitor Timing
VCCX
Pushbutton Reset Function Timing
PBR
VRTX
t < tPB
tRST
tPB
tRST
tDB
RST
RST
tSRST
1536 TD01
1536 TD02
SRST
Power-Fail Detect
tFAIL Fast Undervoltage Detect
SLEW RATE ≤0.1V/µs
FALL TIME ≤ 10ns, VCC3 = 3.3V
3.3V
VRTX
500mV
VCC3 OR
VCC5
300mV
VCC5
tFAIL
tPF
RST
RST
1536 TD03
1536 TD04
U
W
U
U
APPLICATIONS INFORMATION
Operation
The LTC1536 is a low power, high accuracy triple supply
monitoring circuit. This reset generator has two basic
functions: generation of a reset when power supplies are
out of range, and generation of a reset or “soft” reset when
the reset button is pushed. The LTC1536 has the added
feature that when the reset supplies are grossly undervoltage there is a very short delay from undervoltage detect to
assertion of RST.
Supply Monitoring
All three VCC inputs must be above predetermined thresholds for 200ms before the reset output is released. The
LTC1536 will assert reset during power-up, power-down
and brownout conditions on any one or more of the VCC
inputs.
On power-up, either the VCC5 or VCC3 pin can power the
drive circuits for the RST pin. This ensures that RST will
be low when either VCC5 or VCC3 reaches 1V. As long as
any one of the VCC inputs is below its predetermined
threshold, RST will stay a logic low. Once all of the VCC
inputs rise above their thresholds, an internal timer is
started and RST is released after 200ms. RST outputs the
inverted state of what is seen on RST.
RST is reasserted whenever any one of the VCC inputs
drops below its predetermined threshold and remains
asserted until 200ms after all of the VCC inputs are above
their thresholds.
On power-down, once any of the VCC inputs drops below
its threshold, RST is held at a logic low. A logic low of 0.4V
is guaranteed until VCC3 and VCC5 drops below 1V.
Pushbutton Reset
The LTC1536 provides a pushbutton reset input pin. The
PBR input has an internal pull-up current source to VCC3.
If the PBR pin is not used it can be left floating.
7
LTC1536
U
U
W
U
APPLICATIONS INFORMATION
When the PBR is pulled low for less than tPB (≈ 2 sec), a
narrow (100µs typ) soft reset pulse is generated on the
SRST output pin after the button is released. The pushbutton circuitry contains an internal debounce counter
which delays the output of the soft reset pulse by typically
20ms. This pin can be OR-tied to the RST pin and issue
what is called a “soft” reset. The SRST thereby resets the
microprocessor without interrupting the DRAM refresh
cycle. In this manner DRAM information remains undisturbed. Alternatively, SRST may be monitored by the
processor to initiate a software-controlled reset.
When the PBR pin is held low for longer than tPB (≈ 2 sec),
a standard reset is generated. Once the 2-second period
has elapsed, a reset signal is produced by the pushbutton
logic, thereby clearing the reset counter. Once the PBR
pin is released, the reset counter begins counting the
reset period (200ms nominal). Consequently, the reset
outputs remain asserted for approximately 200ms after
the button is released.
Fast Undervoltage for PCI Applications
The LTC1536 is designed for PCI Local Bus applications
that require reset to be asserted quickly in response to one
or both of the power supply rails (5V and 3.3V) going out
of spec. The spec for tFAIL and tPF are met with enough
margin to give the designer the ability to add follow-on
logic as needed by system requirements. The VCCA pin can
be used to monitor the “power good” signal and keep reset
applied until both supplies are in spec and the power good
signal is high.
Glitch Immunity and Fast Undervoltage Detection
The LTC1536 achieves its high speed characteristics while
maintaining glitch immunity by using two sets of comparators. The VCC5 and VCC3 sense inputs each have two
comparators set at different thresholds. A slow, very
accurate comparator monitors the supply for precision
undervoltage detection. In parallel, but with a threshold
250mV lower than the precision threshold, is a very fast
comparator that detects when the supply is quickly going
out of specification. Because the fast comparator threshold is set 250mV above the PCI specification, typical
values for tFAIL can be negative.
3V or 5V Power Detect/Gate Drive
The LTC1536 for the most part is powered internally from
the VCC3 pin. The exception is at the gate drive of the output
FET on the RST pin. On the gate to this FET is power detect
circuitry used to detect and drive the gate from either the
3.3V pin or the 5V pin, whichever pin has the highest
potential. This ensures the part pulls the RST pin low as
soon as either input pin is ≥ 1V.
Extended ESD Tolerance of the PBR Input Pin
The PBR pin is susceptible to ESD since it can be brought
out to a front panel in normal applications. The ESD
tolerance of this pin can be increased by adding a resistor
in series with the PBR pin. A 10k resistor can increase the
ESD tolerance of the PBR pin to approximately 10kV. The
PBR’s internal pull-up current of 7µA typical means there
is only 70mV (150mV max) dropped across the resistor.
U
TYPICAL APPLICATIONS N
Dual Supply Monitor (3.3V and 5V, VCCA Input
Monitoring “Power Good”)
PCI Expansion Board RST Generation
3.3V SUPPLY
LTC1536
0.1µF
PCI
LOCAL
BUS
LTC1536
1
2
5V SUPPLY
0.1µF
3
4
RESET
8
VCC3
PBR
VCC5
SRST
VCCA
RST
GND
RST
8
3.3V
7
5V
6
5
ONBOARD
DEVICE
1536 TA08
PWR GOOD
1
2
3
4
VCC3
PBR
VCC5
SRST
VCCA
RST
GND
RST
8
7
6
SYSTEM RESET
5
1536 TA04
LTC1536
U
TYPICAL APPLICATIONS N
RESET Valid for VCC3 Down to 0V
in a Dual Supply Application
Triple Supply Monitor (3.3V, 5V and Adjustable)
LTC1536
1
3.3V
ADJUSTABLE SUPPLY
OR DC/DC FEEDBACK
DIVIDER
R1
2
5V
3
4
R2
PBR
VCC3
VCC5
SRST
VCCA
GND
RST
RST
8
10k*
PUSHBUTTON
RESET
LTC1536
3.3V
7
6
3
SYSTEM RESET
5
4
VCC5
SRST
VCCA
RST
GND
RST
8
100k
7
6
5
SYSTEM RESET
1536 TA03
Using VCCA Tied to DC/DC Feedback Divider
LTC1435
3.3V
VOSENSE
4.7k
6
ADJUSTABLE
RESET TRIP
THRESHOLD 2.74V
6µA
RST 6
35.7k
1%
LTC1536
3.3V
2.8k
1%
RESET
SRST 7
PBR
2.9V
PUSHBUTTON
8
6µA
VCC3
1536 TA09
SRST Tied to RST and OR-Tying Other Sources to RST to
Generate Reset and Reset
PBR
2
5V
*OPTIONAL RESISTOR EXTENDS
ESD TOLERANCE OF PBR INPUT
8kV TO 10kV
LTC1536
1
22.1k
1%
5V
1
2
3
4
VCC3
PBR
VCC5
SRST
VCCA
RST
GND
RST
8
7
6
SYSTEM RESET
5
1536 TA07
OTHER OPEN DRAIN
RESET SOURCES
OR-TIED TO RESET
VCC3
RST 5
RESET
1536 TA05
9
LTC1536
U
PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
MS8 Package
8-Lead Plastic MSOP
(LTC DWG # 05-08-1660)
0.118 ± 0.004*
(3.00 ± 0.102)
8
7 6
5
0.118 ± 0.004**
(3.00 ± 0.102)
0.192 ± 0.004
(4.88 ± 0.10)
1
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
2 3
4
0.034 ± 0.004
(0.86 ± 0.102)
0° – 6° TYP
0.021 ± 0.006
(0.53 ± 0.015)
SEATING
PLANE 0.012
(0.30)
0.0256
REF
(0.65)
TYP
0.006 ± 0.004
(0.15 ± 0.102)
MSOP (MS8) 1197
* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,
PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
10
LTC1536
U
PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.189 – 0.197*
(4.801 – 5.004)
8
7
6
5
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
1
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.053 – 0.069
(1.346 – 1.752)
0°– 8° TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
2
3
4
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
TYP
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SO8 0996
11
LTC1536
U
TYPICAL APPLICATIONS N
Quad Supply Monitor:
12V: Undervoltage, Overvoltage
5V: Undervoltage, Overvoltage
3.3V: Undervoltage, Overvoltage
– 12V: Undervoltage
3.3V ± 0.3V
3
2.37M
1%
1.21M
1%
0.1µF
100k
LTC1444
LTC1536
4
–
5
+
1
A
2
2
5V
3
12V
5V ± 5%
4.02M
1%
6
–
7
+
1.21M
12V ± 5%
9.31M
1%
10
1.21M
1%
– 12V ±10%
PBR
VCC5
SRST
VCCA
RST
GND
RST
8
7
6
5
SYSTEM
RESET
1.05M
1%
B
1
102k
1%
OPTIONAL
PWR GOOD
–
C
1M
10.7M
1%
4
VCC3
11
+
12
–
13
+
D
16
15
REF
1.221V
8
14
9
HYST
1536 TA07
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC690
5V Supply Monitor, Watchdog Timer and Battery Backup
4.65V Threshold
LTC694-3.3
3.3V Supply Monitor, Watchdog Timer and Battery Backup
2.9V Threshold
LTC699
5V Supply Monitor and Watchdog Timer
4.65V Threshold
LTC1232
5V Supply Monitor, Watchdog Timer and Pushbutton Reset
4.37V/4.62V Threshold
LTC1326
Micropower Precision Triple Supply Monitor
4.725V, 3.118V, 1V Thresholds (±0.75%)
LTC1326-2.5
Micropower Precision Triple Supply Monitor
2.363V, 3.118V, 1V Thresholds (±0.75%)
12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408) 432-1900
FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com
1536f, sn1536a LT/TP 0498 4K • PRINTED IN THE USA
 LINEAR TECHNOLOGY CORPORATION 1997
Similar pages