FN6567 Rev.7.00 Page 1 of 2
July 8, 2016
FN6567
Rev.7.00
July 8, 2016
ISL6296A
FlexiHash™ For Battery Authentication
DATA SHORT
To request the full datasheet, please visit www.intersil.com/products/ISL6296A
The ISL6296A is a highly cost-effective fixed-secret hash engine
based on Intersil’s FlexiHash™ technology. The device’s
authentication is achieved through a challenge response
scheme, which is customized for low-cost applications where
cloning via eavesdropping without knowledge of the device’s
secret code is not economically viable. When used for its
intended applications, the ISL6296A offers the same level of
effectiveness as other significantly more expensive high
maintenance monetary-grade hash algorithm and
authentication schemes.
The ISL6296A has a wide operating voltage range and is
suitable for direct powering from a 1-cell Li-ion/Li-Poly or a
3-cell series NiMH battery pack. The ISL6296A can also be
powered by the XSD bus when the bus pull-up voltage is 3.3V
or higher. The device connects directly to the cell terminals of a
battery pack and includes on-chip voltage regulation circuit,
POR and a noncrystal based oscillator for bus timing
reference.
Communication with the host is achieved through a single-wire
XSD interface (a light-weight subset of Intersil’s ISD bus
interface). The XSD bus is compatible for use with serial ports
offered by all 8250 compatible UARTs or a single GPIO
(General Purpose Input and Output) pin of a microprocessor.
A clone prevention solution utilizing the ISL6296A offers
safety and revenue protection at the lowest cost and power
and is suitable for protection against after-market
replacement for a wide variety of low-cost applications.
Related Literature
•AN1167, “Implementing XSD Host Using a GPIO”
• AN1166, “FlexiHash Engine Algorithm”
Features
• Challenge-response based authentication scheme using
32-bit challenge code and 8-bit authentication code
• Fast and flexible authentication process. Multipass
authentication can be used to achieve the highest security
level if necessary
• 16x8 OTP ROM stores up to three sets of 32-bit host selectable
secrets with additional programmable memory for storage of
up to 48 bits of ID code and/or pack information
• FlexiHash engine uses two sets of 32-bit secrets for
authentication code generation
• Nonunique mapping of the secret key to an 8-bit
authentication code maximizes hacking difficulty due to
need for exhaustive key search (superior to SHA-1)
• Supports 1-cell Li-ion/Li-Poly and 3-cell series NiMH battery
packs (2.6V ~ 4.8V operation), or powered by the XSD bus
• XSD single-wire host bus interface communicates with all
8250-compatible UARTs or a single GPIO. Supports CRC on
read data and transfer bit-rate 5.78kbps
• True “Zero Power” sleep mode - automatically entered after
a bus inactivity time-out period
• 5 Ld SOT-23, 8 Ld TDFN and 8 Ld µTQFN packages
• -25°C to +85°C operating temperature range
• Pb-free (RoHS compliant)
Applications
• Battery pack authentication
•Printer cartridges
• Add-on accessories
• Other nonmonetary authentication applications
FIGURE 1. TYPICAL APPLICATION WITH THE ISL6296A POWERED BY THE BATTERY
FIGURE 2. TYPICAL APPLICATION WITH THE ISL6296A POWERED BY THE XSD BUS
PROTECTIONISL6296A
VSS
VDDXSD
R1R2
C1
D1
PACK+
PACK-
XSD
330Ω 4.7kΩ
5.1V 0.1µF
PROTECTIONISL6296A
VSS
VDDXSD
R1
C1
D1
PACK+
PACK-
XSD
330Ω
5.1V 0.1µF