LM8333
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LM8333 Mobile I/O Companion Supporting Key-Scan, I/O Expansion, PWM, and
ACCESS.bus Host Interface
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1FEATURES DESCRIPTION
The LM8333 Mobile I/O Companion offloads the
2• 8 × 8 Standard Keys burden of keyboard scanning from the host, while
• 8 Special Function Keys (SF Keys) Providing a providing extremely low power consumption in both
Total of 72 Keys for the Maximum Keyboard operational and standby modes. It supports keypad
Matrix matrices up to 8 × 8 in size (plus another 8 special-
function keys), for portable applications such as
• ACCESS.Bus (I2C-compatible) Communication cellphones, PDAs, games, and other handheld
Interface to the Host applications.
• Four General Purpose Host Programmable I/O
Pins with Two Optional (Slow) External Key press and release events are encoded into a
byte format and loaded into a FIFO buffer for retrieval
Interrupts by the host processor. An interrupt output (IRQ) is
• 15-byte FIFO Buffer to Store Key Pressed and used to signal events such as keypad activity, a state
Key Released Events change on either of two interrupt-capable general-
• Error Control with Error Reports on (FIFO purpose I/O pins, or an error condition. Interrupt and
Overrun, Keypad Overrun, Invalid Command) error codes are available to the host by reading
dedicated registers.
• Host Programmable PWM
• Host Programmable Active Time and Four general-purpose I/O pins are available, two of
which have interrupt capability. A pulse-width
Debounce Time modulated output based on a host-programmable
internal timer is also available, which can be used as
APPLICATIONS a general-purpose output if the PWM function is not
• Mobile Phones required.
• Personal Digital Assistants (PDAs) To minimize power, the LM8333 automatically enters
• Smart Handheld Devices a low-power standby mode when there is no keypad,
I/O, or host activity.
• Personal Media Players The device is packaged in a 32–pin WQFN and a
49-pin csBGA. Both are chip-scale packages.
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2006–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
LM8333
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SIGNAL DESCRIPTIONS
Name 32 Pins 49 Pins I/O Description
WAKE_IN0 29 D7 Input Wake-up input/Keyboard scanning input 0
WAKE_IN1 30 C7 Input Wake-up input/Keyboard scanning input 1
WAKE_IN2 27 E7 Input Wake-up input/Keyboard scanning input 2
WAKE_IN3 28 D6 Input Wake-up input/Keyboard scanning input 3
WAKE_IN4 31 B6 Input Wake-up input/Keyboard scanning input 4
WAKE_IN5 32 A7 Input Wake-up input/Keyboard scanning input 5
WAKE_IN6 1 A6 Input Wake-up input/Keyboard scanning input 6
WAKE_IN7 2 B5 Input Wake-up input/Keyboard scanning input 7
K_OUT0 21 G3 Output Keyboard scanning output 0
K_OUT1 22 F4 Output Keyboard scanning output 1
K_OUT2 23 G4 Output Keyboard scanning output 2
K_OUT3 24 G5 Output Keyboard scanning output 3
K_OUT4 3 A5 Output Keyboard scanning output 4
K_OUT5 4 B4 Output Keyboard scanning output 5
K_OUT6 5 A4 Output Keyboard scanning output 6
K_OUT7 6 A3 Output Keyboard scanning output 7
GEN_IO_0 12 D2 I/O General-purpose I/O 0
GEN_IO_1 13 D1 I/O General-purpose I/O 1
GEN_IO_2 7 B3 I/O General-purpose I/O 2
GEN_IO_3 8 A2 I/O General-purpose I/O 3
SDA 25 F7 I/O ACCESS.bus data signal
SCL 26 E6 Input ACCESS.bus clock signal
IRQ 17 F2 Output Interrupt request output
PWM 16 F1 Output Pulse-width modulated output
WD_OUT 18 G1 Output Watchdog timer output (connect to RESET input)
RESET 20 F3 Input Reset input
CLK_IN 11 B1 Input Clock input (connect to ground through a 68k ohm resistor)
VCC 15 E1, E2 n.a. Vcc
GND 9, 10, 14 A1, B2, C3, n.a. Ground
C4, C5, D3,
D4, D5, E3,
E4, E5
NC 19 B7, C1, C2, n.a. No connect
C6, F5, F6,
G2, G6, G7
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Typical Application
Figure 3. Typical Keypad Configuration
FEATURES
The following features are supported:
• 8 x 8 Standard Keys.
• 8 Special Function Keys (SF keys) with Wake-Up Capability by Forcing a WAKE_INx Pin to Ground. Pressing
a SF Key Overrides any other Key in the Same Row.
• A Total of 72 Keys can be Scanned.
• ACCESS.Bus (I2C-Compatible) Interface for Communication with the Host.
• The Watchdog Timer is Mandatory, so WD_OUT Must be Connected to RESET.
I/O EXPANSION OPTIONS
• One Host-Programmable PWM Output which also may be Used as a General-Purpose Output.
• Four Host-Programmable General-Purpose I/O Pins, GEN_IO_0, GEN_IO_1, GEN_IO_2, and GEN_IO_3.
GEN_IO_0 and GEN_IO_1 can also be Configured for “Slow” Interrupts, in which any Transition will Trigger a
Hardware Interrupt Event to the Host.
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WATCHDOG TIMER
The watchdog timer is always enabled in hardware. To use the timer, connect the WD_OUT output to the
RESET input.
HALT MODE
The fully static architecture of the LM8333 allows stopping the internal RC clock in Halt mode, which reduces
power consumption to the minimum level.
Halt mode is entered when no key-press, key-release, or ACCESS.bus activity is detected for a certain period of
time (by default, 500 milliseconds). The mechanism for entering Halt mode is always enabled in hardware, but
the host can program the period of inactivity which triggers entry into Halt mode.
The LM8333 will remain in Active mode as long as a key event, or any other event, which causes the IRQ output
to be asserted is not resolved.
ACCESS.bus Activity
When the LM8333 is in Halt mode, any activity on the ACCESS.bus interface will cause the LM8333 to exit from
Halt mode. However, the LM8333 will not be able to acknowledge the first bus cycle immediately following wake-
up from Halt mode. It will respond with a negative acknowledgement, and the host should then repeat the cycle.
The LM8333 will be prevented from entering Halt mode if it shares the bus with peripherals that are continuously
active. For lowest power consumption, the LM8333 should only share the bus with peripherals that require little
or no bus activity after system initialization.
KEYPAD SCANNING
The LM8333 starts new scanning cycles at fixed time intervals of about 4 ms. If a change in the state of the
keypad is detected, the keypad is rescanned after a debounce delay. When the state change has been reliably
captured, it is encoded and written to the FIFO buffer.
If more than two keys are pressed simultaneously, the pattern of key closures may be ambiguous, so pressing
more than two keys asserts the Error Flag condition and the IRQ output (if enabled). The host may attempt to
interpret the events stored in the FIFO or discard them.
The SF keys connect the WAKE_INx pins directly to ground. There can be up to eight SF-keys. If any of these
keys are pressed, other key presses that use the same WAKE_INx pin will be ignored.
COMMUNICATION INTERFACE
The two-wire ACCESS.bus interface is used to communicate with a host. The ACCESS.bus interface is fully
compliant with the I2Cbus standard. The LM8333 operates as a bus slave at speeds up to 400 kHz.
An ACCESS.bus transfer starts with a byte that includes a 7-bit slave device address. The LM8333 responds to
a fixed device address. This address is 0xA2, when aligned to the MSB (7-bit address mapped to bits 7:1, rather
than bits 6:0). Bit 0 is a direction bit (0 on write, 1 on read).
Because it is a slave, the LM8333 never initiates an ACCESS.bus cycle, it only responds to bus cycles initiated
by the host. The LM8333 may signal events to the host by asserting the IRQ interrupt request.
Interrupts Between the Host and LM8333
The IRQ output is used to signal unresolved interrupts, errors, and key-events to the host.
The host can use an available GEN_IO_0 or GEN_IO_1 pin to interrupt (or wake-up) the LM8333, if it is not
being used for another function. The host can also wake-up the LM8333 by sending a Start Condition on the
ACCESS.bus interface.
NOTE
The LM8333 it will not be able to acknowledge the first byte received from the host after
wake-up. In this case, the host will have to resend the slave address.
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Interrupt Sources
The IRQ output is asserted on these conditions:
• Any new key-event.
• Any error condition, which is indicated by the error code.
• Any enabled interrupt on either of the GEN_IO_0 or GEN_IO_1 pins that can be configured as external
interrupt inputs. When enabled, any rising or falling edge triggers an interrupt.
The IRQ output remains asserted until the interrupt code is read.
Device Operation
EVENT CODE ASSIGNMENT
After power-on reset, the LM8333 starts scanning the keypad. It stays active for a default time of about 500 ms
after the last key is released, after which it enters a standby mode to minimize power consumption (<2 µA
standby current).
Table 1 lists the codes assigned to the matrix positions encoded by the hardware. Key-press events are
assigned the codes listed in Table 1, but with the MSB set. When a key is released, the MSB of the code is
clear.
Table 1. Keypad Matrix Code Assignments
K_OUT0 K_OUT1 K_OUT2 K_OUT3 K_OUT4 K_OUT5 K_OUT6 K_OUT7 SF Keys
WAKE_IN0 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09
WAKE_IN1 0x11 0x12 0x13 0x14 0x15 0x16 0x17 0x18 0x19
WAKE_IN2 0x21 0x22 0x23 0x24 0x25 0x26 0x27 0x28 0x29
WAKE_IN3 0x31 0x32 0x33 0x34 0x35 0x36 0x37 0x38 0x39
WAKE_IN4 0x41 0x42 0x43 0x44 0x45 0x46 0x47 0x48 0x49
WAKE_IN5 0x51 0x52 0x53 0x54 0x55 0x56 0x57 0x58 0x59
WAKE_IN6 0x61 0x62 0x63 0x64 0x65 0x66 0x67 0x68 0x69
WAKE_IN7 0x71 0x72 0x73 0x74 0x75 0x76 0x77 0x78 0x79
The codes are loaded into the FIFO buffer in the order in which they occurred. Table 2 shows an example
sequence of events, and Figure 4 shows the resulting sequence of event codes loaded into the FIFO buffer.
Table 2. Example Sequence of Events
Event Number Event Code Event on Input Matrix Node Description
1 0xF1 Wake_INP7 K_OUT0 Key is pressed
2 0xB6 Wake_INP3 K_OUT5 Key is pressed
3 0x71 Wake_INP7 K_OUT0 Key is released
4 0x36 Wake_INP3 K_OUT5 Key is released
5 0xB4 Wake_INP3 K_OUT3 Key is pressed
6 0x34 Wake_INP3 K_OUT3 Key is released33
7 0x91 Wake_INP1 K_OUT0 Key is pressed
8 0x00 NA NA Indicates end of stored events
Figure 4. Example Event Codes Loaded in FIFO Buffer
I/O EXPANSION
In addition to keypad scanning, the LM8333 supports various I/O expansion options.
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PWM Output with Programmable Duty Cycle
The PWM pin may be used either as a pulse-width modulated output driven by a 16-bit timer or as a general-
purpose output pin. In the PWM mode, the low time (TLO) and high time (THI) are programmable between 1 × tC
and 65K × tCcycles in which tCis the cycle time (nominally 1 microsecond), as shown in Figure 5. The period
TPD is the sum of THI and TLO. The PWM_LO command writes TLO, and the PWM_HI command writes THI.
Operational modes of the PWM pin are controlled by the PWM_CTL command. Before activating the PWM
output, the TLO and THI times must be initialized. Figure 6 shows the command formats.
Figure 5. Programmable PWM
Figure 6. PWM Control Commands for Arbitrary Duty Cycle
Table 3. Summary of PWM Control Bits
OUT_DIR Bit PWM_DIR Bit MOD BIT Description
0 1 0 Drive output low
1 1 0 Drive output high
0 0 0 TRI-STATE® mode
X X 1 PWM timer output
General-Purpose I/O (GPIO)
Figure 7 shows the commands to write, read and control the general-purpose I/O port pins, GEN_IO_0,
GEN_IO_1, GEN_IO_2, and GEN_IO_3.
All general-purpose I/O pins can be programmed as inputs or outputs as shown in Table 4. The GEN_IO_0 and
GEN_IO_1 pins provide an additional capability for programmable wake-up.
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Figure 7. General-Purpose I/O Control Commands
Table 4 shows the pin configuration for all four combinations of control bit settings (data output and direction) for
the general-purpose I/O pins. GEN_IO_3 cannot be put into the high impedance (Hi-Z) input mode. When
programmed as an input, it can only be configured as an input with a weak pullup.
Table 4. General Purpose I/O Pin Configuration
GEN_IO_DIR Bit GEN_IO_OUT Bit Direction State
0 0 Input Hi-Z
0 1 Input Weak Pullup
1 0 Output Drive Low
1 1 Output Drive High
External Interrupts
When the GEN_IO_0 or GEN_IO_1 pins are configured as inputs, a SET_EXT_INT command (0xD1) can be
used to enable receiving external interrupts on either or both of these pins. Setting the EX_0 or EX_1 bits in the
data byte of the SET_EXT_INT command (as shown in Figure 8) enables the corresponding pin as an external
interrupt input. When enabled as an interrupt input, any rising or falling edge causes the IRQ output to be
asserted. If the LM8333 was in Halt mode, it also wakes up into Active mode.
Figure 8. SET_EXT_INT Command Data Byte
When both GEN_IO_0 and GEN_IO_1 are configured as interrupt inputs, bits 1 and 2 of the interrupt code
indicate which input asserted the interrupt. However, if only one of GEN_IO_0 or GEN_IO_1 is configured as an
interrupt input, both bits 1 and 2 of the interrupt code will be set when an interrupt occurs.
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Table 5. Interface Commands for Controlling the LM8333
Function Cmd Dir Data Bits Data Description
Read an event from the FIFO.
Maximum 14 event codes stored in the FIFO.
Event Codes from
FIFO_READ 0x20 R 128 FIFO MSB = 1: key pressed.
MSB = 0: key released.
Repeats a FIFO read without advancing the FIFO pointer,
for example to retry a read after an error.
Event Codes from Maximum 14 event codes stored in the FIFO.
RPT_FIFO_READ 0x21 R 128 FIFO MSB = 1: key pressed.
MSB = 0: key released.
Default is 10 ms. Valid range 1–255.
DEBOUNCE 0x22 W 8 nnnn nnnn Time ~ n × 3 ms
GEN_IO_IN 0x30 R 8 0000 nnnn Read port data.
Specify port mode. (Drive 0 or 1 when the port is configured
GEN_IO_OUT 0x31 W 8 0000 nnnn as an output; select Hi-Z or pullup when the port is
configured as an input.)
GEN_IO_DIR 0x32 W 8 0000 nnnn Select port direction (input or output).
PWM_HI 0x40 W 16 (n+1) × tCSets the low pulse time of the PWM signal.
PWM_LO 0x41 W 16 (n+1) × tCSets the high pulse time of the PWM signal.
PWM_CTL 0x42 W 8 0000 0nnn Activate, reactivate, or stop PWM.
Reads the interrupt code, acknowledges the interrupt,
READ_INT 0xD0 R 8 0000 nnnn deasserts the IRQ output, and clears the code.
Enables/disables external interrupts on GEN_IO_0 and
SET_EXT_INT 0xD1 W 8 0000 00nn GEN_IO_1.
READ_STAT 0xE0 R 8 000n nnnn Status Information.
Requests rescanning the keypad (for example, after an error
SCAN_REQ 0xE3 W 8 was reported).
Specifies the time after the last event during which the
LM8333 stays active before entering Halt mode. The active
time must be greater than the debounce time.
ACTIVE 0xE4 W 8 nnnn nnnn Default is 500 msec
Valid range for n is 1–255
Time ~ n × 3 msec.
READ_ERROR 0xF0 R 8 0nnn nnnn Reads and clears the error code.
HOST COMMAND EXECUTION
Command Structure
All communication with the LM8333 over the ACCESS.bus interface is initiated by the host, usually in response
to an interrupt request (IRQ low) asserted by the LM8333. Figure 9 shows a sequence of Start conditions, slave
addresses, READ_INT command (0xD0), acknowledge cycles, data bytes, and Stop condition for reading the
interrupt code.
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Figure 9. Typical Command Sequence from Host
Every transfer is preceded by a Start condition (S) or a Repeated Start condition (RS). The latter occurs when a
command follows immediately upon another command without an intervening Stop condition (P). A Stop
condition indicates the end of transmission. Every byte is acknowledged (A) by the receiver.
The first byte in a write from the host to the LM8333 is 0xA2, and the first byte in a read is 0xA3. This byte is
composed of a 7-bit slave address in bits 7:1 and a direction bit in bit 0. The direction bit is 0 on writes from the
host to the slave and 1 on reads from the slave to the host.
The second byte sends the command. The commands are listed in Table 5. In the example, the READ_INT
command (0xD0) reads the interrupt code.
The slave address is repeated in the third byte, with the direction bit set to 1. The Start (or Repeated Start)
condition must be repeated whenever the slave address or the direction bit is changed. In this case, the direction
bit is changed.
The data is sent from the slave to the host in the fourth byte. When the master is the receiver, it sends a
negative acknowledgement (NA) to indicate the end of the data.
HOST WRITE COMMANDS
Some host commands include one or more data bytes written to the LM8333. Figure 10 shows a SET_EXT_INT
command, which consists of an address byte, a command byte, and one data byte.
The first byte is composed of a 7-bit slave address in bits 7:1 and a direction bit in bit 0. The state of the direction
bit is 0 on writes from the host to the slave and 1 on reads from the slave to the host.
The second byte sends the command. The commands are listed in Figure 11. The SET_EXT_INT command is
0xD1.
The third byte send the data, in this case configuring GEN_IO_0 as an external interrupt input.
Figure 10. Host Write Command
HOST READ COMMANDS
NOTE: All NSIDs perform as described in this section. NSID LM8333GGR8AXS is an enhanced version which
also allows the use of a STOP START sequence in addition to the REPEATED_START sequence described in
this section.
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Some host commands include one or more data bytes read from the LM8333. Figure 11 shows a READ_INT
command which consists of an address byte, a command byte, a second address byte, and a data byte.
The first address byte is sent with the direction bit driven low to indicate a write transaction of the command to
the LM8333. The second address byte is sent with the direction bit undriven (pulled high) to indicate a read
transaction of the data from the LM8333.
The Repeated Start condition must be repeated whenever the slave address or the direction bit is changed. In
this case, the direction bit is changed.
The data is sent from the slave to the host in the fourth byte. This byte ends with a negative acknowledgement
(NACK) to indicate the end of the data.
Figure 11. Host Read Command
WAKE-UP FROM HALT MODE
Any bus transaction initiated by the host may encounter the LM8333 device in Halt mode or busy with processing
data, such as controlling the FIFO buffer or executing interrupt service routines.
Figure 12 shows the case in which the host sends a command while the LM8333 is in Halt mode (CPU clock is
stopped). Any activity on the ACCESS.bus wakes up the LM8333, but it cannot acknowledge the first bus cycle
immediately after wake-up.
The host drives a Start condition followed by seven address bits and a R/W bit. The host then releases SDA for
one clock period, so that it can be driven by the LM8333.
If the LM8333 does not drive SDA low during the high phase of the clock period immediately after the R/W bit,
the bus cycle terminates without being acknowledged (shown as NACK in Figure 12). The host then aborts the
transaction by sending a Stop condition. After aborting the bus cycle, the host may then retry the bus cycle. On
the second attempt, the LM8333 will be able to acknowledge the slave address, because it will be in Active
mode.
Alternatively, the I2C specification allows sending a START byte (00000001), which will not be acknowledged by
any device. This byte can be used to wake up the LM8333 from Halt mode.
The LM8333 may also stall the bus transaction by pulling the SCL low, which is a valid behavior defined by the
I2C specification.
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Figure 12. LM8333 Responds with NACK, Host Retries Command
Interrupts
INTERRUPT CODE
The interrupt code is read and acknowledged with the READ_INT command (0xD0). This command clears the
code and deasserts the IRQ output. Table 6 shows the format of the interrupt code.
Note that when only one of the interrupt-capable pins GEN_IO_0 or GEN_IO_1 is configured as an interrupt
input, bits 1 and 2 are both set when an interrupt occurs. When both GEN_IO_0 and GEN_IO_1 pins are
configured as interrupt inputs, only one bit corresponding to the interrupt source is set when an interrupt occurs.
Table 6. Interrupt Code
7 6 5 4 3 2 1 0
0 0 0 0 ERROR EX_1 EX_0 KEYPAD
Bit Description
ERROR An error condition occurred.
EX_1 A rising or falling edge was detected on GEN_IO_1.
EX_0 A rising or falling edge was detected on GEN_IO_0.
KEYPAD A key-press or key-release event occurred.
ERROR CODE
If the LM8333 reports an error, the READ_ERROR command (0xF0) is used to read and clear the error code.
Table 7 shows the format of the error code.
Table 7. Error Code
7 6 5 4 3 2 1 0
0 FIFOOVR 0 NOINT 0 KEYOVR CMDUNK CMDOVR
Bit Description
FIFOOVR Key event occurred while the FIFO was full.
NOINT Interrupt deasserted before it could be serviced.
KEYOVR More than two keys were pressed simultaneously.
CMDUNK Not a valid command.
CMDOVR Command received before it could be accepted, e.g. after wake-up.
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STATUS CODES
The host can use the READ_STAT command (0xE0) to read the status code, for example to synchronize after
an error.
Table 8. Status Codes
Status Code Description
Reset 0000 0000 Default after reset.
Wake Up Interrupt 0000 0010 Wake-up caused by external interrupt.
Ack 0000 0110 Last host command was successful.
NoAck 0001 0101 Last host command was not successful.
INTERRUPT PROCESSING
Unexpected states encountered during run-time, for example overrun of the FIFO buffer, are reported as errors.
When the host receives an interrupt from the LM8333, it uses a READ_INT command to read the interrupt code.
If the code has a set ERROR bit, the host then uses a READ_ERROR command to read the error code, as
shown in Figure 13.
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COMMAND EXECUTION SUMMARY
• With the interrupt, status, and error codes, the LM8333 provides the features needed to support a reliable
key-scan functionality.
• Up to 14 key-scan events can be stored in an internal FIFO buffer. The end of buffer is indicated with the 00
(empty character) code.
• The host can repeatedly read the FIFO without modifying the FIFO pointer using the RPT_FIFO_READ
command (0x21), for example if an error is encountered during a read.
• The LM8333 asserts the IRQ output low when a new character is pressed after the last interrupt acknowledge
from the host. The IRQ output will be deasserted after the host has acknowledged the interrupt by reading the
interrupt code using the READ_INT command (0xD0).
• The host can synchronize with the LM8333 by reading the status code with the READ_STAT command
(0xE0). The status code verifies whether the last command was successfully completed.
• Two GPIO pins on the LM8333 may be configured as external interrupt inputs. A rising or falling edge on an
enabled interrupt input triggers wake-up from Halt mode and asserts an interrupt to the host by pulling the
IRQ output low.
• The host can change the debounce time from the default time of 10 ms. This can be used for reliable
scanning of keyboards with noisy contacts. The debounce time can be set to about 1 second in steps of 4
milliseconds. The debounce time is set with the DEBOUNCE command (0x22).
• The host can change the active time permitted before entering Halt mode from the default period of 500 ms.
The active time is the time during which the keypad is scanned after the last key is released, before entering
Halt mode. The active time must be longer than the debounce time.
• The host can program the direction and output state of four general-purpose I/O pins. The host can also read
the states on these pins.
• The host can program a 16-bit timer for generating a PWM output. If the PWM function is not used, the PWM
pin can be used as a general-purpose output.
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These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ABSOLUTE MAXIMUM RATINGS (1)(2)
Supply Voltage (VCC) 3.5V
Voltage at Any Pin -0.3V to VCC +0.3V
Maximum Input Current Without Latchup ±100 mA
ESD Protection Level
Human Body Model 2 kV
Machine Model 200V
Total Current into VCC Pin (Source) 80 mA
Total Current out of GND Pin (Sink) 60 mA
Storage Temperature Range −65°C to +140°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but specific performance is not specified. For specifications and test conditions, see the
Electrical Characteristics tables.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
DC ELECTRICAL CHARACTERISTICS
(Temperature: -40°C ≤TA ≤+85°C)
Data sheet specification limits are specified by design, test, or statistical analysis.
Symbol Parameter Conditions Min (1) Typ Max (1) Units
VCC Operating Voltage 2.25 2.9 V
Power Supply Rise Time from 0.0V 20 µs 10 ms
(On Chip Power-On Reset Selected)
IDD Supply Current (2) RC Clock = 10 MHz, 6 mA
VCC = 2.75V, TC= 1 µs (3)
IHALT Standby Mode Current (4) VCC = 2.75V, TC= 0 µs, (3), TA<2 15 µA
= 25°C
VIL Logical 0 Input Voltage 0.25 VCC V
VIH Logical 1 Input Voltage 0.8 VCC V
Hi-Z Input Leakage (TRI-STATE Output) VCC = 2.75V -0.1 0.1 µA
Input PullupCurrent VCC = 2.75V, VIN = 0V -15 -120 µA
Port Input Hysteresis (5) 0.1 V
Output Current Source (Weak Pull-Up) VCC = 2.25V, VOH = 1.7V -10 -80 µA
Output Current Source (Push-Pull Mode) VCC = 2.25V, VOH = 1.7V -10 mA
Output CurrentSink (Push-Pull Mode) VCC = 2.25V, VOL = 0.4V 10 mA
Allowable Sink and Source Current per Pin 16 mA
CPAD Input Capacitance 8.5 pF
(1) Data sheet minimum and maximum limits are specified by design, test, or statistical analysis.
(2) Supply current is measured with inputs connected to VCC and outputs driven low but not connected to a load.
(3) TC= instruction cycle time (min. 0.7 µs).
(4) In Halt mode, the internal clock is switched off. Supply current in Halt mode is measured with inputs connected to VCC and outputs
driven low but not connected to a load.
(5) Specified by design, not tested.
Copyright © 2006–2013, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LM8333
LM8333
SNLS246K –SEPTEMBER 2006–REVISED MAY 2013
www.ti.com
AC ELECTRICAL CHARACTERISTICS
(Temperature: -40°C ≤TA≤+85°C)
Data sheet specification limits are specified by design, test, or statistical analysis.
Parameter Conditions Min (1) Typ Max (1) Units
External R from CLK_IN to GND 0.75 µs
(R = 68 kΩ)
Internal Oscillator 2.25V ≤VCC ≤2.75V
System Oscillator (mclk) External R from CLK_IN to GND 75 ns
(R = 68 kΩ)
2.25V ≤VCC ≤2.75V
System Oscillator and Internal Frequency Variation 2.25V ≤VCC ≤2.75V ±30 %
Input Pulse Width Low 0.7 µs
Input Pulse Width High 0.7
ACCESS Bus Input Signals:
Bus Free time Between Stop and Start Condition 16
(IBUFI)(1)(2)
SCL Setup Time (tCSTOsi) (1)(2) Before Stop Condition 8
SCL Hold Time (tCSTRhi) (1)(2) After Stop Condition 8
SCL Setup Time (tCSTRsi) (1)(2) Before Start Condition 8 mclk
Data High Setup Time (tDHCsi)(1)(2) Before SCL Rising Edge (RE) 2
Data Low Setup Time (tDLCsi)(1)(2) Before SCL RE 2
SCL Low Time (tSCLlowi)(1) After SCL Falling Edge (FE) 12
SCL High Time (tSCLhighi)(1)(2) After SCL RE 12
SDA Hold Time (tSDAhi)(1) After SCL FE 0
SDA Setup Time (tSDAsi)(1)(2) Before SCL RE 2
ACCESS Bus Output Signals After SCL FE 7 mclk
SDA Hold Time (tSDAho)(3)
(1) Specified by design, test, or statistical analysis.
(2) The ACCESS.bus interface implements and meets the timing necessary for interface to the I2C bus and SMBus protocol at logic levels.
The bus drivers are designed with open-drain output as required for bidirectional operation. Due to System Oscillator (mclk) Variation,
this specification may not meet the AC timing and current/voltage drive requirements of the full bus specification.
(3) Specified by design, test, or statistical analysis.
Figure 14. ACCESS.bus Start and Stop Condition Timing
18 Submit Documentation Feedback Copyright © 2006–2013, Texas Instruments Incorporated
Product Folder Links: LM8333
LM8333
www.ti.com
SNLS246K –SEPTEMBER 2006–REVISED MAY 2013
REVISION HISTORY
Changes from Revision J (May 2013) to Revision K Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 18
Copyright © 2006–2013, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LM8333
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead finish/
Ball material
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LM8333FLQ8X/NOPB ACTIVE WQFN NJE 32 2500 RoHS & Green SN Level-3-260C-168 HR -40 to 85 LM8333F
LM8333FLQ8Y/NOPB ACTIVE WQFN NJE 32 250 RoHS & Green SN Level-3-260C-168 HR -40 to 85 LM8333F
LM8333GGR8AXS/NOPB ACTIVE csBGA NYC 49 1000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85 8333AXS
LM8333GGR8AXSX/NOPB ACTIVE csBGA NYC 49 3500 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 85 8333AXS
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 2
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM8333FLQ8X/NOPB WQFN NJE 32 2500 330.0 16.4 6.3 6.3 1.5 12.0 16.0 Q1
LM8333FLQ8Y/NOPB WQFN NJE 32 250 178.0 16.4 6.3 6.3 1.5 12.0 16.0 Q1
LM8333GGR8AXS/NOPB csBGA NYC 49 1000 178.0 12.4 4.3 4.3 1.5 8.0 12.0 Q1
LM8333GGR8AXSX/NOP
BcsBGA NYC 49 3500 330.0 12.4 4.3 4.3 1.5 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 24-Aug-2017
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM8333FLQ8X/NOPB WQFN NJE 32 2500 367.0 367.0 38.0
LM8333FLQ8Y/NOPB WQFN NJE 32 250 210.0 185.0 35.0
LM8333GGR8AXS/NOPB csBGA NYC 49 1000 210.0 185.0 35.0
LM8333GGR8AXSX/NOPB csBGA NYC 49 3500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 24-Aug-2017
Pack Materials-Page 2
MECHANICAL DATA
NYC0049A
www.ti.com
GRA49A (Rev A)
MECHANICAL DATA
NJE0032A
www.ti.com
LQA32A (REV A)
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