INTERSIL ISL6125

ISL6123, ISL6124, ISL6125,
ISL6126, ISL6127, ISL6128
®
Data Sheet
January 2004
FN9005.2
Power Sequencing Controllers
Features
The Intersil ISL6123, ISL6124, ISL6125, ISL6126, ISL6127,
ISL6128 are integrated 4 channel controlled-on/controlled-off
power-supply sequencers with supply monitoring, fault
protection and a “sequence completed” signal (RESET#). For
larger systems, more than 4 supplies can be sequenced by
simply connecting a wire between SYSRESET# pins of
cascaded IC's. The ISL6125 uses 4 open-drain outputs to
control the 4 power supplies, and the other sequencers use a
patented, micropower 7X chargepump to drive 4 external lowcost NFET switch gates above the supply rail by 5.3V. These
IC's can be biased from any supply 5V down to 1.5V. Individual
product descriptions are below.
• Enables arbitrary turn-on and turn-off sequencing of up to
four power supplies (0.7V - 5V)
The four channel ISL6123 (ENABLE input), ISL6124 (ENABLE#
input) and ISL6125 ICs offer the designer 4 rail control when it
is required that all four rails are in minimal compliance prior to
turn on and that compliance must be maintained during
operation. The ISL6123 has a low power standby mode when it
is disabled, suitable for battery powered applications.
• 1µA Sleep State (ISL6123)
• Active high (ISL6123) or low (ISL6124) ENABLE# input
• Open drain version available (ISL6125)
• Pre programmed Sequence available (ISL6127)
• Dual channel groupings (ISL6128)
• QFN Package:
- Compliant to JEDEC PUB95 MO-220
QFN - Quad Flat No Leads - Package Outline
- Near Chip Scale Package footprint, which improves
PCB efficiency and has a thinner profile
Applications
• Graphics cards
• FPGA/ASIC/microprocessor/PowerPC supply sequencing
• Network routers
• Telecommunications systems
AIN
BIN
CIN
COUT
Ordering Information
SYSRST#
PKG. DWG. #
-40 to +85
24 Ld 4x4 QFN L24.4x4
ISL6127IR
-40 to +85
24 Ld 4x4 QFN L24.4x4
ISL6128IR
-40 to +85
AIN
DLY_OFF_D
24 Ld 4x4 QFN L24.4x4
ISL6126IR
DLY_ON_D
24 Ld 4x4 QFN L24.4x4
-40 to +85
DLY_OFF_C
-40 to +85
ISL6125IR
GROUND
DLY_ON_C
ISL6124IR
UVLO_C
UVLO_D
DLY_OFF_B
24 Ld 4x4 QFN L24.4x4
UVLO_B
DLY_ON_B
-40 to +85
DLY_OFF_A
ISL6123IR
UVLO_A
RESET#
DLY_ON_A
PACKAGE
BIN
DOUT
VDD
ENABLE
TEMP. RANGE (oC)
BOUT
DIN
For volume applications, other programmable options and
features can be had. Contact the factory with your needs.
PART NUMBER
AOUT
CIN
Additional I/O is provided indicating and driving RESET state in
various configurations.
• Under voltage lockout for each supply
DIN
External resistors provide flexible voltage threshold programming
of monitored rail voltages. Delay and sequencing are provided by
external capacitors for both ramp up and ramp down.
• Glitch immunity
GATE A
The ISL6128 has two groups of two channels each with its
independent I/O and is ideal for voltage sequencing into
redundant capability loads as all four inputs need to be satisfied
prior to turn on but a single group fault is ignored by the other
group.
• Multiple sequencers can be daisy-chained to sequence an
infinite number of independent supplies
GATE B
The ISL6127 is a preprogrammed A-B-C-D turn-on and D-C-B-A
turn-off sequenced IC. Once all inputs are in compliance and
ENABLE is asserted the sequencing starts and each subsequent
GATE will turn-on after the previous one completes turning-on.
• Adjustable voltage slew rate for each rail
GATE C
In contrast to the ISL6123 and ISL6124, with the ISL6126, each
of the four channels operates independently so that the various
rails will turn on once its individual input voltage requirements
are met.
• Supplies VDD +5.3V of charge pumped gate drive
GATE D
The ISL6125 operates like the ISL6124 but instead of charge
pump driven gate drive outputs it has open drain logic outputs
for direct interface to other circuitry.
• Operates from 1.5V to 5V supply voltage
24 Ld 4x4 QFN L24.4x4
ISL612XSEQEVAL1
Evaluation Platform
1
FIGURE 1. TYPICAL ISL6123 APPLICATION USAGE
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2004 All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Pinout
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128 (QFN)
TOP VIEW
24
23 22
21 20
19
1
18
2
17
16
3
15
4
14
5
13
6
7
9
8
10
11
12
4mm X 4mm
Pin Descriptions
PIN #
PIN NAME
FUNCTION
DESCRIPTION
23
VDD
Chip Bias
Bias IC from nominal 1.5V to 5V
10
GND
Bias Return
IC ground
1
ENABLE_1/
ENABLE#_1
Input to start on/off
sequencing.
11
ENABLE#_2
Input to initiate the start of the programmed sequencing of supplies on or off. Enable
functionality is disabled for 10ms after UVLO is satisfied. ISL6123 has ENABLE. ISL6124,
ISL6125, ISL6126 and ISL6127 have ENABLE#. Only ISL6128 has 2 ENABLE# inputs,
1 for each 2 channel grouping. EN_1# for (A, B), and EN_2# for (C, D).
24
RESET#
RESET# Output
9
RESET#_2
RESET# provides a low signal 150ms after all GATEs are fully enhanced. This delay is for
stabilization of output voltages. RESET# will assert low upon UVLO not being satisfied or
ENABLE/ENABLE# being deasserted. The RESET outputs are open drain N channel FET
and is guaranteed to be in the correct state for VDD down to 1V and is filtered to ignore fast
transients on VDD and UVLO_X.
RESET#_2 only exists on ISL6128 for (C, D) group I/O.
20
UVLO_A
12
UVLO_B
17
UVLO_C
14
UVLO_D
21
DLY_ON_A
8
DLY_ON_B
16
DLY_ON_C
15
DLY_ON_D
18
DLY_OFF_A
13
DLY_OFF_B
3
DLY_OFF_C
4
DLY_OFF_D
2
GATE_A
5
GATE_B
6
GATE_C
7
GATE_D
22
SYSRST#
19
No Connect
Under Voltage Lock These inputs provide for a programmable UV lockout referenced to an internal 0.633V
reference and are filtered to ignore short (<30µs) transients below programmed UVLO
Out/Monitoring
level.
Input
Gate On Delay
Timer Output
Allows for programming the delay and sequence for Vout turn-on using a capacitor to
ground. Each cap is charged with 1µA, 10ms after turn-on initiated by ENABLE/ENABLE#
with an internal current source providing delay to the associated FETs GATE turn-on.
These pins are NC on ISL6126 and ISL6127
Gate Off Delay
Timer Output
Allows for programming the delay and sequence for Vout turn-off through
ENABLE/ENABLE# via a capacitor to ground. Each cap is charged with a 1µA internal
current source to an internal reference voltage causing the corresponding gate to be pulled
down turning-off the FET.
These pins are NC on ISL6127
FET Gate Drive
Output
ISL6125 Open
Drain Outputs
Drives the external FETs with a 1µA current source to soft start ramp into the load.
On the ISL6125 only, these are open drain outputs that can be pulled up to a
maximum of VDD voltage.
System Reset I/O
As an input, allows for immediate and unconditional latch-off of all GATE outputs when
driven low. This input can also be used to initiate the programmed sequence with ‘zero’ wait
(no 10ms stabilization delay) from input signal on this pin being driven high to first GATE.
As an output when there is a UV condition this pin pull low. If common to other SYSRST#
pins in a multiple IC configuration it will cause immediate and unconditional latch-off of all
other GATEs on all other ISL612X sequencers.
This pin is a NC on ISL6126 and ISL6128
No Connect
No Connect
2
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
ISL612X Variant Feature Matrix
NUMBER
OF
NUMBER OF CHANNELS
THAT
UVLO
REQUIRED
TURN-OFF
INPUTS
GATE DRIVE CONDITION
WHEN 1
MONITORED
S FOR
OR OPEN
UVLO
BY EACH
INITIAL
DRAIN
CMOS/
FAULTS
RESET#
START-UP
OUTPUTS
TTL
PRESET OR
ADJUSTABLE
SEQUENCE
NUMBER OF
UVLO AND
PAIRS OF I/O
4 Gates
Adjustable On &
Off
4 Monitors with Auto restart
1 I/O
4 Gates
Adjustable On &
Off
4 Monitors with Auto restart
1 I/O
4 Open Drain Adjustable On &
Off
4 Monitors with Auto restart
1 I/O
PART
NAME
EN/EN#
ISL6123
EN
TTL
Gate Drive
4 UVLO
1 EN
4 UVLO
ISL6124
EN#
CMOS
Gate Drive
4UVLO
1 EN
4 UVLO
ISL6125
EN#
CMO
Open Drain
4 UVLO
1 EN
4 UVLO
ISL6126
EN#
CMOS
Gate Drive
1 UVLO
1 EN
4 UVLO
1 Gate
Adjustable Off
ISL6127
EN#
CMOS
Gate Drive
4 UVLO
1 EN
4 UVLO
4 Gates
Preset
ISL6128
EN#
CMOS
Gate Drive
4 UVLO
2 EN
2 UVLO
2 Gates
Preset
3
FEATURES
4 Monitors with Gates
1 I/O
independent
on as UVLO Valid
4 Monitors with Auto restart
1 I/O
2 Monitors
with 2 I/O
Dual Redundant
Operation
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Absolute Maximum Ratings
Thermal Information
VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6.0V
GATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to VDD+6V
ISL6125 LOGIC OUT. . . . . . . . . . . . . . . . . . . . . -0.3V to VDD +0.3V
UVLO, ENABLE, ENABLE#, SYSRST# . . . . . . -0.3V to VDD +0.3V
RESET#, DLY_ON, DLYOFF . . . . . . . . . . . . . . -0.3V to VDD +0.3V
ESD Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0kV (HBM)
Thermal Resistance (Typical, Notes 1, 2)
θJA (oC/W)
θJC (oC/W)
4 x 4 QFN Package . . . . . . . . . . . . . . .
48
9
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . .150oC
Maximum Storage Temperature Range . . . . . . . . . -65oC to 150oC
Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . .300oC
(QFN - Leads Only)
Operating Conditions
VDD Supply Voltage Range . . . . . . . . . . . . . . . . . . . . +1.5V to +5.5V
Temperature Range (TA) . . . . . . . . . . . . . . . . . . . . . . -40oC to 85oC
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTES:
1. θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
2. For θJC, the “case temp” location is the center of the exposed metal pad on the package underside.
3. All voltages are relative to GND, unless otherwise specified.
VDD = 1.5V to +5V, TA = TJ = -40oC - 85oC, Unless Otherwise Specified.
Electrical Specifications
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
619
633
647
mV
-
40
-
nV/oC
-
10
-
mV
UVLO
Undervoltage Lockout Threshold
VUVLOvth
TJ = +25oC
TJ = -40oC to 85oC
Undervoltage Lockout Threshold Temp Co
TCUVLOvth
Undervoltage Lockout Hysteresis
VUVLOhys
Undervoltage Lockout Threshold Range
RUVLOvth
Max VUVLOvth- Min VUVLOvth
-
7
-
mV
Undervoltage Lockout Delay
TUVLOdel
ENABLE satisfied
-
10
-
ms
VDD, UVLO, ENABLE glitch filter
-
30
-
µs
0.92
1
1.08
µA
Transient Filter Duration
TFIL
DELAY ON/OFF
Delay Charging Current
DLY_ichg
-
0.08
-
µA
TC_DLY_ichg
-
0.2
-
nA/oC
DLY_Vth
1.238
1.266
1.294
V
TC_DLY_Vth
-
0.2
-
mV/oC
-
1.2
-
V
Delay Charging Current Range
DLY_ichg_r
Delay Charging Current Temp. Coeff.
Delay Threshold Voltage
Delay Threshold Voltage Temp. Coeff.
VDLY = 0V
DLY_ichg(max) - DLY_ichg(min)
ENABLE/ENABLE#, RESET# & SYSRST# I/O
ENABLE Threshold
VENh
ENABLE# Threshold
VENh
-
VDD/2
-
V
ENABLE/ENABLE# Hysteresis
VENh -VENl
Measured at VDD = 1.5V
-
0.2
-
V
ENABLE/ENABLE# Lockout Delay
TdelEN_LO
UVLO satisfied
-
10
-
ms
RESET# Pull-Down Current
IRSTpd
RST = 0.1V
-
13
-
mA
RESET# Delay after GATE High
TRSTdel
GATE = VDD+5V
-
160
-
ms
Measured at VDD = 5V with 5K
pullup resistors
-
-
0.001
V
GATE = 80% of VDD+5V
-
40
-
ns
RESET# Output Low
VRSTl
SYSRST# Low to GATE Turn-off
TdelSYS_G
GATE
GATE Turn-On Current
IGATEon
GATE Turn-Off Current
IGATEoff_l
GATE Current Range
IGATE_range
GATE Turn-On/Off Current Temp. Coeff.
TC_IGATE
GATE Pull-Down High Current
IGATEoff_h
4
GATE = 0V
0.8
1.1
1.4
µA
GATE = VDD, Disabled
-1.4
-1.05
-0.8
µA
-
-
0.35
µA
-
0.2
-
nA/oC
-
88
-
mA
Within IC IGATE max-min
GATE = VDD, UVLO = 0V
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
VDD = 1.5V to +5V, TA = TJ = -40oC - 85oC, Unless Otherwise Specified. (Continued)
Electrical Specifications
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNIT
VDD+5V
VDD+5.3V
-
V
GATE High Voltage
VGATEh
Gate High Voltage
GATE Low Voltage
VGATE_
Gate Low Voltage, VDD = 1V
-
0
0.1
V
IC Supply Current
IVDD_5V
VDD = 5V
-
0.20
0.5
mA
IC Supply Current
IVDD_3.3V
VDD = 3.3V
-
0.14
-
mA
IC Supply Current
IVDD_1.5V
VDD = 1.5V
-
0.10
-
mA
VDD = 5V, ENABLE = 0V
-
-
1
µA
-
-
1
V
BIAS
ISL6123 Stand By IC Supply Current
VDD Power On Reset
IVDD_sb
VDD_POR
ISL6123, ISL6124, ISL6125 Descriptions
and Operation
The ISL6123, ISL6124, ISL6125 sequencer family consists
of several four channel voltage sequencing controllers in
various functional and personality configurations. All are
designed for use in multiple-voltage systems requiring
power sequencing of various supply voltages. Individual
voltage rails are gated on and off by external N-Channel
MOSFETs, the gates of which are driven by an internal
charge pump to VDD +5.3V (VQP) in a user programmed
sequence.
With the four-channel ISL6123 the ENABLE must be
asserted and all four voltages to be sequenced must be
above their respective user programmed Under Voltage
Lock Out (UVLO) levels before programmed output turn on
sequencing can begin. Sequencing and delay
determination is accomplished by the choice of external
cap values on the DLY_ON and DLY_OFF pins. Once all 4
UVLO inputs and ENABLE are satisfied for 10ms, the four
DLY_ON caps are simultaneously charged with 1µA
current sources to the DLY_Vth level of 1.27V. As each
DLY_ON pin reaches the DLY_Vth level its associated
GATE will then turn-on with a 1µA source current to the
VQP voltage of VDD+5.3V. Thus all four GATEs will
sequentially turn on. Once at DLY_Vth the DLY_ON pins
will discharge to be ready when next needed. After the
entire turn on sequence has been completed and all
GATEs have reached the charge pumped voltage (VQP), a
160ms delay is started to ensure stability after which the
RESET# output will be released to go high. Subsequent to
turn-on, if any input falls below its UVLO point for longer
than the glitch filter period (~30µs) this is considered a
fault. RESET# and SYSRST# are pulled low and all GATEs
are simultaneously also pulled low. In this mode the GATEs
are pulled low with 88mA. Normal shutdown mode is
entered when no UVLO is violated and the ENABLE is
deasserted. When ENABLE is deasserted, RESET# is
asserted and pulled low. Next, all four shutdown ramp caps
on the DLY_OFF pins are charged with a 1µA source and
when any ramp-cap reaches DLY_Vth, a latch is set and a
current is sunk on the respective GATE pin to turn off its
external MOSFET. When the GATE voltage is
5
approximately 0.6V, the GATE is pulled down the rest of
the way at a higher current level. Each individual external
FET is thus turned off removing the voltages from the load
in the programmed sequence.
The ISL6123 and ISL6124 have the same functionality
except for the ENABLE active polarity with the ISL6124
having an ENABLE# input. Additionally the ISL6123 also
has an ultra low power sleep state when ENABLE is low.
The ISL6125 has the same personality as the ISL6124 but
instead of charged pump driven GATE outputs it has open
drain LOGIC outputs that can be pulled up to a maximum of
VDD.
The ISL6126 is unique in that it’s sequence on is not time
determined but voltage determined. It’s personality is that each
of the four channels operates independently so that once the IC
is biased and any one of the UVLO inputs is greater than the
0.63V internal reference, and ENABLE# input is also satisfied
the GATE for the associated UVLO input will turn-on. In turn the
other UVLO inputs need to be satisfied for the associated
GATEs to turn-on. 150ms after all GATEs are fully on (GATE
voltage = VQP) the RESET# is released to go high. The UVLO
inputs can be driven by either a previously turned on output rail
offering a voltage determined sequence or by logic signal
inputs. Any subsequent UVLO level < its programmed level will
pull the RESET# output low (if previously released), but will not
latch-off the other outputs. Predetermined turn-off is
accomplished by signaling ENABLE# high, this will cause
RESET# to latch low and all four GATE outputs to follow the
programmed turn off sequence similar to a ISL6124.
The ISL6127 is a four channel sequencer pre-programmed for
A-B-C-D turn-on and D-C-B-A turn-off. After all four UVLO and
ENABLE# inputs are satisfied for ~10ms, the sequencing starts
and the next GATE in the sequence starts to ramp up once the
previous GATE has reached ~VQP-1V. 160ms after the last
GATE is at VQP the RESET# output will be deasserted. Once
any UVLO is unsatisfied, RESET# is pulled low, SYSRST# is
pulled low and all GATEs are simultaneously turned off. When
ENABLE# is signaled high the D GATE will start to pull low and
once below 0.6V the next GATE will then start to pull low and
so on until all GATEs are at 0V. Unloaded, this turn off
sequence will complete in <1ms. This variant offers a lower
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
cost and size implementation as the external delay caps are not
used. Since the delay caps are not used this IC can not delay
the start of subsequent GATEs thus necessary stabilization or
system house keeping need to be considered.
The ISL6128 is a four channel device that groups the four
channels into two groups of two channels each, as A, B and
C, D. Each group having its own ENABLE# and RESET# I/IO
pins. This requires all four UVLO and both ENABLE#s to be
satisfied for sequencing to start. The A, B group will first turn on
10ms after the second ENABLE# is pulled low with A then B
turning on followed by C then D. Once the preceding GATE =
VQP the next DLY_ON pin starts to charge its capacitor thus
turning on all four GATEs. Approximately 160ms after D GATE
= VQP the RESET# output is released to go high. Once any
UVLO is unsatisfied, only the related group’s RESET# and two
GATEs are pulled low. The related EN input has to be cycled
for the faulted group to be turned-on again. Normal shutdown is
invoked by either signaling both ENABLE# inputs high which
will cause all the two related GATEs to shutdown in reverse
order from turn-on. DLY_X caps adjust the delay between
GATES during turn on and off but not the order.
During bias up the RESET# output is guaranteed to be in
the correct state with VDD lower than 1V.
The SYSRST# pin is a true I/O connection having both
functions. As an input, if it is pulled low all GATEs will
unconditionally shut off and RESET# pulls low, see Figure
6. This input can be used as a no wait enabling input, if all
inputs (ENABLE & UVLO) are satisfied it does not wait
through the ~10ms enable delay to initiate DLY_ON cap
charging. It is also useful when multiple sequencers are
implemented in a design needing simultaneous shutdown
(kill switch) across all sequencers. As an output, after the
on sequence is completed it will pull low after any UVLO is
unsatisfied longer than TFIL and pull all other SYSRST#
inputs low on common connection thus unconditionally
shutting down all outputs across multiple sequencers.
Except ISL6128 after a fault, restart of the turn on
sequence is automatic once all requirements are met. This
allows for no interaction between the sequencer and a
controller IC if desired. The ENABLE & RESET# I/O do
allow for a higher level of feedback and control if desired.
The ISL6128 requires that the related ENABLE# be cycled
for restart of its associated group GATEs.
6
If no capacitors are connected between DLY_ON or
DLY_OFF pins and ground then all such related GATEs
start to turn on immediately after the 10ms (TUVLOdel)
ENABLE stabilization time out has expired and the GATEs
start to immediately turn off when ENABLE is asserted.
If some of the rails are to be sequenced together, in order to
eliminate the effect of capacitor variance on the timing and to
reduce cost, a common capacitor can be connected to two
or more DLY_ON or DLY_OFF pins. In this case multiply the
capacitor value by the number of common DLY_X pins to
retain the desired timing.
Table 1 illustrates the nominal time delay from the start of
charging to the 1.27V reference for various capacitor
values on the DLY_X pins. This table does not include the
10ms of enable lock out delay during a start up sequence
but represents the time from the end of the enable lock out
delay to the start of GATE transition. There is no enable
lock out delay for a sequence off, so this table illustrates
the delay to GATE transition from a disable signal.
TABLE 1.
NOMINAL DELAY TO SEQUENCING THRESHOLD
DLY PIN CAPACITANCE
TIME (s)
Open
0.00006
100pF
0.00013
1000pF
0.0013
0.01µF
0.013
0.1µF
0.13
1µF
1.3
10µF
13
NOTE: Nom. TDEL_SEQ = Cap (µF) * 1.3MΩ.
Figure 2 illustrates the turn-on and Figure 3 the nominal turnoff
timing diagram of the ISL6123 and ISL6124 product.
The ISL6125 is similar except the open drains instead of GATE
pins are pulled up to VDD.
Note the delay and flexible sequencing possibilities.
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
l
VUVLOVth
<TFIL
UVLO_A
VUVLOVth
UVLO_B
VUVLOVth
UVLO_C
VUVLOVth
TUVLOdel
UVLO_D
ENABLE# (ISL6124)
VEN
ENABLE (ISL6123)
DLY_Vth
DLYON_B
DLY_Vth
DLYON_D
DLY_Vth
DLYON_A
DLY_Vth
DLYON_C
VQPUMP
VQPUMP
VQPUMP
GATE_B
VQPUMP
GATE_D
VQPUMP-1V
GATE_C
TRSTdel
GATE_A
RESET#
FIGURE 2. ISL6123/ISL6124 TURN-ON AND GLITCH RESPONSE TIMING DIAGRAM
UVLO_X>VUVLOVth
ENABLE(ISL6123)
VEN
ENABLE# (ISL6124)
DLY_Vth
DLYOFF_A
DLY_Vth
DLYOFF_B
DLY_Vth
DLYOFF_C
DLY_Vth
DLYOFF_D
GATE_C
GATE_D
GATE_A
GATE_B
RESET#
FIGURE 3. ISL6123/ISL6124 TURN-OFF TIMING DIAGRAM
7
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Typical Performance Curves
1.04
634
1.03
VDD = 5V
632
DLY CURRENT SOURCE (µA)
UV THRESHOLD (mV)
633
631
630
VDD = 1.5V
629
628
627
626
-40
-20
0
20
40
60
80
100
1.02
1.01
1.00
VDD = 1.5V
0.99
DLY_OFF/ON
0.98
VDD = +5V
0.97
-40
-20
0
20
40
60
80
100
TEMPERATURE (oC)
TEMPERATURE (oC)
FIGURE 4. UVLO THRESHOLD VOLTAGE
FIGURE 5. DLY CHARGE CURRENT
GATE
5VOUT
3.3VOUT
SYSRST#
2V/DIV
1µs/DIV
FIGURE 6. SYSRST# LOW TO OUTPUT LATCH OFF
Using the ISL612XSEQEVAL1 Platform
The ISL612XSEQEVAL1 platform is the primary evaluation
board for this family. The board has 2 complete, separate
and electrically identical circuits, see Figure 15 for schematic
and Figure 16 for a photo.
In the top right hand corner of the board is a SMD layout with
a ISL6123 illustrating the full functionality and small
implementation size for an application having the highest
component count.
The majority of the board is given over to a socket and
discrete through-hole components circuit for ease of
evaluation flexibility through IC variant swapping and
modification of UVLO levels and sequencing order by
passive component substitution.
The board is shipped with the ISL6123 installed in both
locations and with two each of the other released variant
types loose packed. As this sequencer family has a common
function pinout there are no major modifications to the board
8
necessary to evaluate the other ICs. The ISL6125 due to its
having open drain outputs can be evaluated on the
ISL612XSEQEVAL1 with a minor modification or on the
ISL613XSUPEREVAL2 evaluation platform. To modify for
ISL6125 evaluation, pull-up resistors must be added from
the GATE outputs to a pull-up voltage of 1.5V to prevent
FET turn-on or remove FETs to eliminate this voltage
restriction.
To the left, right and above the socket are four test point
strips (TP1-TP4). These give access to the labeled IC I/O
pins during evaluation. Remember that significant current or
capacitive loading of particular I/O pins will affect
functionality and performance.
Attention to orientation and placement of variant ICs in the
socket must be paid to prevent IC damage or faulty
evaluation.
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
The default configuration of the ISL612XSEQEVAL1
circuitries was built around the following design
assumptions:
1. Using the ISL6123IR or ISL6124IR
2. The four supplies being sequenced are 5V (IN_A), 3.3V
(IN_B), 2.5V (IN_C) and 1.5V (IN_D), the UVLO levels
are ~ 80% of nominal voltages. Resistors chosen such
that the total resistance of each divider is ~ 10K using
standard value resistors to approximate 80% of
nominal = 0.63V on UVLO input.
3. The desired order turn-on sequence is first both 5V and
3.3V supplies together and then the 2.5V supply about
75ms later and lastly the 1.5V supply about 45ms later.
4. The desired turn-off sequence is first both 1.5V and 3.3V
supplies at the same time then the 2.5V supply about
50ms later and lastly the 5V supply about 72ms after that.
All scope shots taken from ISL612xSEQEVAL1 board.
Figures 7 and 8 illustrate the desired turn-on and turn-off
sequences respectively. The sequencing order and delay
between voltages sequencing is set by external capacitance
values so other than illustrated can be accomplished.
Figures 9 and 10 illustrate the timing relationships between
the EN input, RESET#, DLY and GATE outputs and the
VOUT voltage for a single channel being turned on and off
respectively. RESET# is not shown in Figure 9 as it asserts
160ms after the last GATE goes high.
All IC family variants share similar function for DLY_X
capacitor charging, GATE and RESET# operation. Figures
11 through 14 illustrate the principal feature and functional
differences for each of the ISL6125, ISL6126, ISL6127 and
ISL6128 variants, each is described below.
Figure 11 features the 6125 open drain outputs being
sequenced on and off along with RESET# relatiionship
which is similar to all other family variants.
Figure 12 illustrates the independent input feature of the
ISL6126 which allows once the EN# is low for each UVLO to
be individually satisfied and for its associated GATE to turnon. Only when the last variable VIN is satisfied as shown
does the RESET# release to signal all input voltages are
valid.
Figure 13 shows the ISL6127 pre programmed ABCD on
DCBA off order of sequencing with minimal non adjustable
delay between each.
Figure 14 demonstrates the independence of the redundant
two rail sequencer. It shows that either one of the two groups
can be turned off and the ABCD order of restart with
capacitor programmable delay once both EN inputs are
pulled low.
Typical Performance Waveforms
5VOUT
5VOUT
RESET#
ENABLE#
3.3VOUT
3.3VOUTPUT
2.5VOUT
2.5VOUT
1.5VOUT
1.5VOUT
ENABLE#
1V/DIV
40ms/DIV
FIGURE 7. ISL6124 SEQUENCED TURN-ON
9
1V/DIV
20ms/DIV
FIGURE 8. ISL6124 SEQUENCED TURN-OFF
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Typical Performance Waveforms
TdelENLO
(Continued)
GATE 2V/DIV
3.3VO 1V/DIV
DLY_Vth
GATE 2V/DIV
3.3VO 1V/DIV
DLY_Vth
RESET# 2V/DIV
EN 2V/DIV
DLY_ON 1V/DIV
DLY_OFF 1V/DIV
EN 2V/DIV
10ms/DIV
FIGURE 9. ISL6123 SINGLE CHANNEL TURN-ON
4ms/DIV
FIGURE 10. ISL6123 SINGLE CHANNEL TURN-OFF
VIN_VAR
EN#
STATIC EN/ALL OTHER VOUT
RESET#
VOUT_VAR
LOGIC A-D STATUS
OUTPUTS
TRSTdel
RESET#
100ms/DIV
FIGURE 11. ISL6125 LOGIC OUTPUTS SEQUENCED ON AND
OFF AND RESET# RELATIONSHIP
FIGURE 12. ISL6126 UVLO INPUT/OUTPUT INDEPENDANCE
AND RESET# RELATIONSHIP
EN#_1 5V/DIV
A_VOUT
EN#_2 5V/DIV
B_VOUT
C_VOUT
A_VOUT
D_VOUT
B_VOUT
C_VOUT
D_VOUT
FIGURE 13. ISL6127 PREPROGRAMMED ABCD TURN-ON AND
DCBA TURN-OFF
10
FIGURE 14. ISL6128 GROUP INDEPENDANT TURN-OFF & DELAY
ADJUSTABLE PREPROGRAMMED TURN-ON
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
+3.3V
1.5V
+2.5V
+5V
C1
EN1
1
1
1
11
EN2
28
VDD
ENABLE1 DLY_ON_B
DLY_ON_D
ENABLE2
R1
7.681K
R3
4.99K
R5
5.98K
1µF
8
15
DLY_ON_C 16
21
DLY_ON_A
R7
5.45K
14
17
20
C6
0.01µF
C3
0.068µF
0.1µF
C7
0.01µF
U1
12
C2
UVLO_B
DLY_OFF_C
UVLO_D
DLY_OFF_D
UVLO_C
DLY_OFF_B
UVLO_A
DLY_OFF_A
3
C4
4
13
0.047µF
C5
18
0.01µF
C8
0.01µF
C9
0.1µF
ISL6123IR
R2
2.26K
R4
4.99K
R5
3.01K
R6
1.47K
GATE_A
GATE_B
GATE_C
SYSRST#
1
22
SYSRST#
GATE_D
2
5
NC
RESET#2
25
EP
GND
RESET#1
Q1
3
7 8 SI4922DY
6
2
7
5 6
SI4922DY
4
Q2
9
2
Q1
1
R10
20
19
5 6 SI4922DY
4
1
R9 750
SI4922DY
3
7 8
2
750
10
RL5
FIGURE 15. EVAL BOARD SCHEMATIC
FIGURE 16. EVAL BOARD PHOTOGRAPH
11
Q2
1
10
RL3
5
RL2
5
RL1
2
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
TABLE 2. ISL612XSEQEVAL1 BOARD COMPONENT LISTING
COMPONENT
DESIGNATOR
DUT1
COMPONENT FUNCTION
COMPONENT DESCRIPTION
ISL6124, 4 Supply Sequencer
Intersil, ISL6124IR 4 Supply Sequencer
Voltage Rail Switches
SI4922DY or equiv, Dual 8A, 30V, 0.018Ω, N-Channel MOSFET
R7
5V to UVLO_A Resistor for Divider String
8.45kΩ 1%, 0402
R8
UVLO_A to GND Resistor for Divider String
1.47kΩ 1%, 0402
R1
3.3V to UVLO_B Resistor for Divider String
7.68kΩ 1%, 0402
R2
UVLO_B to GND Resistor for Divider String
2.26kΩ 1%, 0402
R5
2.5V to UVLO_C Resistor for Divider String
6.98kΩ 1%, 0402
R6
UVLO_C to GND Resistor for Divider String
3.01kΩ 1%, 0402
R3
1.5V to UVLO_D Resistor for Divider String
4.99kΩ 1%, 0402
R4
UVLO_D to GND Resistor for Divider String
4.99kΩ 1%, 0402
R9
RESET#1 LED Current Limiting Resistor
750Ω 10%, 0805
R10
RESET#2 LED Current Limiting Resistor
750Ω 10%, 0805
C7
5V turn-on Delay Cap. (13ms)
0.01µF 10%, 6.3V, 0402
C9
5V turn-off Delay Cap. (130ms)
0.1µF 10%, 6.3V, 0402
C2
3.3V turn-on Delay Cap. (13ms)
0.01µF 10%, 6.3V, 0402
C5
3.3V turn-off Delay Cap. (3ms)
0.01µF 10%, 6.3V, 0402
C3
2.5V turn-on Delay Cap. (88ms)
0.068µF 10%, 6.3V, 0402
C4
2.5V turn-off Delay Cap. (61ms)
0.047µF 10%, 6.3V, 0402
C6
1.5V turn-on Delay Cap. (130ms)
0.1µF 10%, 6.3V, 0402
C8
1.5V turn-off Delay Cap. (13ms)
0.01µF 10%, 6.3V, 0402
C1
Decoupling Capacitor
0.1µF, 0805
D1
RESET#1 Indicating LED
0805, SMD LEDs Red
D2
RESET#2 Indicating LED
0805, SMD LEDs Red
Q1, Q2
TP1 - TP24
Test Points Number Corresponds to DUT Pin Number
RL5
5V Load Resistor
10Ω 20%, 3W Carbon
RL3
3.3V Load Resistor
5Ω 20%, 3W Carbon
RL2
2.5V Load Resistor
5Ω 20%, 3W Carbon
RL1
1.5V Load Resistor
2Ω 20%, 3W Carbon
12
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Application Implementations
Multiple Sequencer Implementations
In order to control the sequencing of more than 4 voltages,
several of the ISL6123, ISL6124, ISL6125 or ISL6127
devices can be variously configured together to accomplish
this. There may be concerns of a particular implementation
that would make a particular configuration preferable over
another. The fundamental questions to answer to determine
which configuration is best suited for your applications are;
If the mere presence of some voltage potential is adequate
prior to sequencing on then a small number of standard logic
AND gates can be used to accomplish this. The block
diagram in Figure 18 illustrates this voltage presence
configuration.
OE
LOW = RESET
1. What level of voltage assurance is needed prior to
sequencing on and can the voltage supplies be grouped
into high and low criticality?
2. Is there a critical maximum time window all supplies must
be present at load or is there a first and a second group
preference possibly with some work done in between the
two groups of voltages being present?
Three configurations are described and illustrated here.
In applications where the integrity of critical voltages must be
assured prior to sequencing, additional monitoring of the
critical supplies is needed. If the compliance of the voltage is
critical for either under voltage and or over voltage the
ISL613X family of supervisors can be employed to provide
this additional assurance across multiple sequencers, see
document FN9115 for supervisor data sheet. Figure 17 is a
block diagram of this voltage compliant, high assurance, low
risk configuration showing the ISL613X supervisor and a mix
of FET switched outputs and logic output sequencers
(ISL6124 and ISL6125 ICs).
ISL613Xs
MONITORING
ON ALL RAILS
VMON
PGOOD
LOW = RESET
SYSRST#
UVLO
en
RESET#
G
A
T
E
ENABLE#
SYSRST#
ISL6125
# N+1
POWER
SUPPLY
RESET#
UVLO
L
O
G
I
C
FIGURE 17. ISL612X & ISL613X VOLTAGE COMPLIANT
SEQUENCING BLOCK DIAGRAM
13
ISL6124
#N
UVLO
en
RESET#
G
A
T
E
ENABLE#
ENABLE#
RESET#’
SYSRST#
ISL6125
# N+1
POWER
SUPPLY
RESET#
UVLO
L
O
G
I
C
In either case the sequencing is straight forward across
multiple sequencers as all DLY_ON capacitors will
simultaneously start charging ~10ms after the common
ENABLE input signal is delivered. This allows the choice of
capacitors to be related to each other no different than using
a single sequencer. When the common enabling signal is
deasserted these configurations will then execute the turnoff sequence across all sequencers as programmed by the
DLY_OFF capacitor values.
In both cases with all the SYSRST# pins bussed together
once the on sequence is complete simultaneous shutdown
upon any UVLO input failure is assured as SYSRST# output
will momentarily pull low turning off all GATE and LOGIC
outputs.
ENABLE#
RESET#
SYSRST#
FIGURE 18. MULTIPLE ISL612X USING LOGIC GATES FOR
VOLTAGE PRESENCE DETECT
OE
ISL6124
#N
UVLO
There may be applications that require or allow groups of
supplies being brought up in sequence and supplies within
each group to be sequenced. Figure 19 illustrates such a
configuration that allows the first group of supplies to turn-on
before the second group starts. This arrangement does not
necessarily preclude adding the assurance of all supplies
prior to turn-on sequencing as previously shown but it will
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
prevent the turn-on sequence from completing if there is one
unsatisfied UVLO input in a group. Using this configuration
involves waiting through the TUVLOdel and TRSTdel (total of
~160ms) for each sequencer IC in the chain for the final
RESET# to release. Once ENABLE on the first sequencer is
deasserted all the RESET# outputs will quickly pull low and
thus allow the sequenced turn-off of this configuration to
ripple through several banks as quickly as the user
programmed sequence as chosen by the DLY_OFF
capacitors allow. Once again with common bussed
SYSRTS# pins, simultaneous shut down of all GATEs and
LOGIC down upon an unsatisfied UVLO input is assured
once all FETs or LOGIC output are on.
It is suggested that this circuit implementation be prototyped
and evaluated for the particular expected loads prior to
committing to manufacturing build.
OE
LOW= RESET
SYSRST#
ISL6124
#N
UVLO
ENABLE
ENABLE#
FIGURE 20. OUTPUT VOLTAGE ON LOW TO HIGH TRACKING
G
A
T
E
RESET#
ENABLE#
SYSRST#
ISL6125
# N+1
POWER
SUPPLY
RESET#
UVLO
L
O
G
I
C
RESET#
FIGURE 21. OUTPUT VOLTAGE HIGH TO LOW TRACKING
RESET#
FIGURE 19. MULTIPLE ISL612X SERIAL CONFIGURATION
Voltage Tracking
In some applications the various voltages may have to track
each other as they ramp up & down whereas others may just
need sequencing. In these cases tracking can be
accomplished and has been demonstrated over a wide
range of load current (1A to 10A) and load capacitance
(10µF to 3300µF) with the ISL612X family. Figures 20 and
21 illustrate output voltage ramping tracking performance,
note that differences are less than 0.5V. With the relevant
GATE pins tied together in a star pattern, so that the
resistance between any two GATE pins is equivalent (1K to
10K) results in a sharing of the GATE ramping voltage and
with the same or similar enough FETs this behavior is
observed.
14
Negative Voltage Sequencing
They ISL612X family can use the charged pump GATE
output to drive FETs that would control and sequence
negative voltages down to a nominal -5V with minimal
additional external circuitry. Figure 22 shows turn-on of 5V
bipolar supplies together then the +2.5V and turn-off of both
positive supplies being turned off together after the -5V.
Figure 23 shows the minimal additional external circuitry to
accomplish this. The 5V zener or schottky diode is used to
level shift the GATE drive down 5V to prevent premature
turn-on when GATE = 0V. Once GATE drive voltage > Vz
then FET Vgs > 5V ensuring full turn-on once GATE gets to
VDD+5.3V. Turn-on and turn-off ramp rate can be adjusted
with FET gate series resistor value. Sequencing of the -V rail
is accomplished as normal via the DLY_X capacitor value
although adjustments in prototyping should be factored in to
fine tune for actual circuit requirements.
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Figures 24 and 25 illustrate a high accuracy -V detection
circuit using the ISL6131and a low cost low accuracy -V
detect circuit and respectively.
Application Considerations
Timing Error Sources
In any system there are variance contributors, for the ISL612X
family the timing errors are mainly contributed by three sources.
Capacitor Timing Mismatch Error
Obviously, the absolute capacitor value is an error source
thus lower percentage tolerance capacitors help to reduce
this error source. Figure 26 illustrates a difference of 0.57ms
between two DLY_X outputs ramping to DLY_X threshold
voltage, these 5% capacitors were from a common source.
In applications where two or more GATEs or LOGIC outputs
must have concurrent transitions, it is recommended that a
common DLY_X cap. be used to eliminate this timing error.
FIGURE 22. ±VOLTAGE SEQUENCING
-Vout
-Vin
R1
ISL612X GATE
Additional 2 components
necessary for -V control
and sequencing.
D1
D1 necessary to prevent premature turn-on. R1 is used
to hold FET Vgs = 0V until D1 Vz is overcome. R1 value
can be changed to adjust -V ramp rates. Choose a R1
value between 4MΩ and 10MΩ initially and fine tune
resistor value for the particular need.
FIGURE 23. -VOLTAGE FET DRIVE CIRCUIT
+V
+BIAS
R1
VMON
R2
R3
(1K)
R5
(10K)
ISL6131
OR
ISL6536A PGOOD R4
(15K)
-BIAS
Q1 Si1300DL
OR EQUIV.
R6
-V
FIGURE 26. CAPACITOR TIMING MISMATCH
DLY_X Threshold Voltage and Charging Current
Mismatch
The two other error sources come from the IC itself and are
the differences in the DLY_X threshold voltage, (DLY_Vth)
when the GATE charging latch is set and the DLY_X
charging current, (DLY_ichg) across the four individual I/Os.
Both of these parameters are bounded by specification and
Figure 27 illustrates that with a common capacitor the typical
error contributed by these factors is insignificant as both
DLY_X traces overlay each other.
TO UVLO OF
ISL612X FOR
-V CONTROL AND
SEQUENCING
R1 and R2 define -V UVLO level
R3 ensures supervisor (ISL6131 or ISL6536A) PGOOD pull-up
R4 and R5 provide Q1 gate bias between 0V and +V
to 0V (resistor values suitable for -V = -5V and +V = +3.3V)
FIGURE 24. HGH ACCURACY -V LOCK OUT
+V
R1
TO UVLO OF ISL612X FOR CONTROL
AND SEQUENCING OF -V
R2
-V
Chose R1 and R2 values to drive UVLO
high when -V is sufficiently present
FIGURE 25. LOW ACCURACY -V PRESENCE DETECTION
15
FIGURE 27. DLY_VTH AND DLY_ICHG TIMING MISMATCH
ISL6123, ISL6124, ISL6125, ISL6126, ISL6127, ISL6128
Quad Flat No-Lead Plastic Package (QFN)
Micro Lead Frame Plastic Package (MLFP)
L24.4x4
24 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE
(COMPLIANT TO JEDEC MO-220VGGD-2 ISSUE C)
MILLIMETERS
SYMBOL
MIN
NOMINAL
MAX
NOTES
A
0.80
0.90
1.00
-
A1
-
-
0.05
-
A2
-
-
1.00
A3
b
0.18
D
0.23
9
0.30
5, 8
4.00 BSC
D1
D2
9
0.20 REF
-
3.75 BSC
1.95
2.10
9
2.25
7, 8
E
4.00 BSC
-
E1
3.75 BSC
9
E2
1.95
e
2.10
2.25
7, 8
0.50 BSC
-
k
0.25
-
-
-
L
0.30
0.40
0.50
8
L1
-
-
0.15
10
N
24
2
Nd
6
3
Ne
6
3
P
-
-
0.60
9
θ
-
-
12
9
Rev. 2 10/02
NOTES:
1. Dimensioning and tolerancing conform to ASME Y14.5-1994.
2. N is the number of terminals.
3. Nd and Ne refer to the number of terminals on each D and E.
4. All dimensions are in millimeters. Angles are in degrees.
5. Dimension b applies to the metallized terminal and is measured
between 0.15mm and 0.30mm from the terminal tip.
6. The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 identifier may be
either a mold or mark feature.
7. Dimensions D2 and E2 are for the exposed pads which provide
improved electrical and thermal performance.
8. Nominal dimensions are provided to assist with PCB Land Pattern
Design efforts, see Intersil Technical Brief TB389.
9. Features and dimensions A2, A3, D1, E1, P & θ are present when
Anvil singulation method is used and not present for saw
singulation.
10. Depending on the method of lead termination at the edge of the
package, a maximum 0.15mm pull back (L1) maybe present. L
minus L1 to be equal to or greater than 0.3mm.
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
16