intersil ISL88694 DATA SHEET
®
www.BDTIC.com/Intersil
ISL88694
Data Sheet January 21, 2005
SMBus Accelerator (SMA)
The ISL88694 SMBus accelerator (SMA) is a dual active
pull-up bus terminator designed to improve data
transmission speed on SMBus or similar 2-wire serial bus
interfaces. The ISL88694 is also compatible to the I
bus.
The SMA detects rising input transitions with two internal
voltage references and two comparators per channel. After
the voltage on a data line crosses the first threshold
(V
), the boost pull-up current source is activated to
TRIPL
speed transition. After the voltage crosses the second
threshold (V
), the boost pull-up current source is de-
TRIPH
activated, leaving an active pull-up current of 275µA on the
line. When both channels are HIGH, the pull-up current for
both lines is reduced to 100µA to save power. Internal logic
ensures that the active and boost pull-up current sources are
not activated during downward transitions.
The level for V
referred to V
DD
is controlled by a bandgap voltage
TRIPH
. This feature makes the switching behavior
invariant for all power supply voltages between 2.7V and
5.5V.
A noise filter on each channel prevents the circuit from
responding to input transitions that do not exceed a voltagetime threshold. To activate the boost circuit, the input must
exceed V
by 100Vns (typical) (See Figure 10).
TRIPL
The SMA permits operation of the bus at frequencies up to
100kHz, despite the capacitive loads of multiple devices
and/or long PC board traces. Enhanced ESD protection on
the accelerator pins are guaranteed to withstand 8kV ESD
(HBM) events.
The SMBus Accelerator provides an essential function in
SMBus applications because of distributed capacitance of
SMBus and multiple device input capacitances at various
nodes. By incorporating SMA, systems using SMBus or I
can reliably increase their bus load without the risk of data
loss.
2
C serial
2
C
FN8239.1
Features
• Active Termination for SMBus lines
• Enhances System Bus Signal Rise Time
• Increases Bus Capacity While Guaranteeing Data Integrity
• 2.2mA Rise Time Supply Current
• 8kV ESD Protection on SDA and SCL Pins
• Wide Operating Voltage Range: 2.7V to 5.5V
2
• 2-Wire SMBus and I
C Compatible (100kHz)
• Small Package - SOT23-5
• Pin-for-Pin Compatible with the LTC1694
• Pb-Free Available (RoHS Compliant)
Target Applications
•Servers
• Data Acquisition
•Routers
• Battery Chargers
• Portable Instrumentation
• Notebook
•PC
• Facilities Tracking System
Pinout
ISL88694
(5 LD SOT-23)
TOP VIEW
V
DD
GND
N.C.
1
2
3
5
SMBus1
4
SMBus2
Ordering Information
PART NUMBER PACKAGE TEMP RANGE (°C)
ISL88694IH5 5-pin SOT -40 to 85
ISL88694IH5Z (Note) 5-pin SOT (Pb-Free) -40 to 85
Add “-TK” suffix for tape and reel.
NOTE: Intersil Pb-free products employ special Pb-free material
sets; molding compounds/die attach materials and 100% matte tin
plate termination finish, which are RoHS compliant and compatible
with both SnPb and Pb-free soldering operations. Intersil Pb-free
products are MSL classified at Pb-free peak reflow temperatures that
meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
1
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.
All other trademarks mentioned are the property of their respective owners.
Copyright Intersil Americas Inc. 2005. All Rights Reserved
ISL88694
www.BDTIC.com/Intersil
Pin Descriptions
SOT-23 SYMBOL DESCRIPTION
1V
DD
Supply Voltage
2 GND Ground
3 N.C. No Connect
4 SMBus1 Active Pull-Up for SMBus
5 SMBus2 Active Pull-Up for SMBus
System Diagram
ISL88694
V
DD
SMBus1
SMBus2
GND
BUS SIGNALS
DATA
CLK
Devices;
SBS, PCI,
Compact PCI,
PMCI, ACPI,
ICMB, IPMI,
IPMB,SMBus,
2
C, 2-Wire.
I
IC Block Diagram
Control
Control
DATA IN
OUT
DAT A
CLK IN
CLK
1.825mA
V
TRIPH
+
V
DD
V
V
V
DD
V
-0.5V
TRIPL
0.75V
TRIPH
-0.5V
TRIPL
0.75V
-
+
-
+
-
+
-
175µA100µA
=
=
=
=
CLK IN
OUT
CLK
Device 1 Device N
OUT
DATA IN
OUT
DAT A
V
DD
SMBus1
SMBus2
1.825mA
175µA100µA
2
8kV ESD
8kV ESD
Protection
Protection
V
DD
GND
FN8239.1
January 21, 2005
ISL88694
www.BDTIC.com/Intersil
Absolute Maximum Ratings Recommended Operating Conditions
Supply Voltage Range . . . . . . . . . . . . . . . . . . . . . . . . . . . -1V to 6.5V
Operating Junction Temperature . . . . . . . . . . . . . . . . . . . . . . +135°C
Storage Temperature Range . . . . . . . . . . . . . . . . . .-65°C to +150°C
Voltage on pins . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to V
Lead temperature (soldering, 10 seconds) . . . . . . . . . . . . . . .300°C
ESD min other pins (HBM). . . . . . . . . . . . . . . . . . . . . . . . . . . . .>2kV
ESD SMBus1 and SMBus2 pins (HBM) . . . . . . . . . . . . . . . . . .>8kV
CAUTION: Absolute Maximum Ratings indicate limits beyond which permanent damage to the device and impaired reliability may occur. These are stress ratings
provided for information only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this
specification are not implied.
For guaranteed specifications and test conditions, see Electrical Specifications. The guaranteed specifications apply only for the test conditions listed. Some
performance characteristics may degrade when the device is not operated under the listed test conditions.
DD
+0.3V
Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
Supply Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 5.5V
Electrical Specifications Over operating conditions unless otherwise specified, Typical values are measured at V
= +25°C
T
A
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT
ANALOG PARAMETERS
V
DD
V
DD RAMPVDD
I
DD
I
OUT_SB
I
OUT_A1
I
OUT_A2
I
OUT_B1
I
OUT_B2
V
TRIPL
V
TRIPH
f
MAX
NSS Noise Spike Suppression
NOTES:
1. Measured as area under triangular waveform above V
Supply Voltage Range 2.7 5.5 V
Ramp Rate 0.05 50 V/msec
Supply Current SMBus1=SMBus2=Open 80 100 µA
Standby Pull-Up Current SMBus1=SMBus2=VDD-1.0V 80 125 µA
Active Pull-Up Current SMBus1=GND; SMBus2=Open 125 275 350 µA
SMBus1= Open; SMBus2=GND 125 275 350 µA
Boost Pull-Up Current (Figure 1) V
Input Voltage Threshold Low 0.65 0.75 0.85 V
Input Voltage Threshold High VDD-0.60 VDD - 0.50 VDD - 0.40 V
SMBus Max Frequency 100 kHz
(Note 1) (Figure 10)
TRIPL
V
TRIPL
<SMBus1<V
<SMBus2<V
, with time as base and VIN as height (See Figure 10).
TRIPL
, SMBus2=Open 1.6 2.2 mA
TRIPH
, SMBus1=Open 1.6 2.2 mA
TRIPH
20 V-nsec
= 3.3V and
DD
3
FN8239.1
January 21, 2005
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