AMD INGAM386SX-40 High-performance, low-power, embedded microprocessor Datasheet

FINAL
Am386®SX/SXL/SXLV
High-Performance, Low-Power, Embedded Microprocessors
DISTINCTIVE CHARACTERISTICS
■ Member of the E86™ CPU series
– 16-bit data bus
– 24-bit address bus
– 16-Mbyte address range
– Long-term stable supply from AMD
■ 40-, 33- and 25-MHz operating speeds
■ Ideal for embedded applications
– True Static design for low-power applications
– 3–5 V operation (at 25 MHz)
– Ideal for cost-sensitive designs
– True DC (0 MHz) operation
■ Industry Standard Architecture
– Supports world’s largest software base for x86
architectures
– Wide range of chipsets and BIOS available
– Fully compatible with all 386SX systems and
software
■ System Management Mode (SMM) for system
and power management (Am386SXLV only)
– System Management Interrupt (SMI) for power
management independent of processor
operating mode and operating system
– SMI coupled with I/O instruction break feature
provides transparent power off and auto resume
of peripherals which may not be “power aware”
– SMI is non-maskable and has higher priority
than Non-Maskable Interrupt (NMI)
– Automatic save and restore of the
microprocessor state
■ 100-lead Plastic Quad Flat Pack (PQFP) package
■ Extended temperature version available
GENERAL DESCRIPTION
The Am386®SX/SXL/SXLV microprocessors are lowcost, high-performance CPUs for embedded applications. Embedded customers benefit from using the
Am386 microprocessor in a number of ways.
The Am386SX/SXL/SXLV microprocessors provide
embedded customers access to very inexpensive processors and the highest performance of any 386SX
available anywhere. The 16-bit data path allows for inexpensive memory design. Full static operation, coupled with 3-V supplies, benefit customers who desire
low-power designs. Standby Mode allows the
Am386SXL/SXLV microprocessors to be clocked
down to 0 MHz (DC) and retain full register contents. A
float pin places all outputs in a three-state mode to facilitate board test and debug.
Additionally, the Am386SXLV microprocessor comes
with System Management Mode (SMM) for system and
power management. SMI (System Management Interrupt) is a non-maskable, higher priority interrupt than
NMI and has its own code space (1 Mbyte in Real
Mode and 16 Mbyte in Protected Mode). SMI can be
coupled with the I/O instruction break feature to implement transparent power management of peripherals.
SMM can be used by system designers to implement
system and power management code independent of
the operating system or the processor mode.
Since the Am386SX/SXL/SXLV microprocessors are
supported as an embedded product in the E86 family,
customers can rely on long-term supply of product, and
extended temperature products.
In addition, customers have access to the largest selection of inexpensive development tools, compilers,
and chipsets. A large number of PC operating systems
and Real Time Operating Systems (RTOS) support the
Am386SX/SXL/SXLV microprocessors. This means
cheaper development costs, and improved time to market.
The Am386SX/SXL/SXLV microprocessor is available
in a small footprint 100-pin Plastic Quad Flat Pack
(PQFP) package.
Publication# 21020 Rev: A Amendment/0
Issue Date: April 1997
F I N A L
ORDERING INFORMATION
Standard Products
AMD standard products are available in several packages and operating ranges. The order number (Valid Combination) is
formed by a combination of the elements below.
I
NG
80386
SX
–40
SPEED OPTION
–40 = 40 MHz
–33 = 33 MHz
–25 = 25 MHz
PROCESSOR TYPE
SX
= SX Processor
SXL = SX Processor with Static Clock Implementation
SXLV = SXL Processor with Low-Voltage and SMI
PROCESSOR FAMILY
Am386 Family
PACKAGE TYPE
NG=100-Lead Plastic Quad Flat Pack (PQB-100)
TEMPERATURE RANGE
Blank = Commercial (TCASE = 0°C to +100°C)
I = Industrial (TCASE = –40°C to +100°C)
Valid Combinations
Valid Combinations
–25
NG80386 SX
–33
–40
SXL
SXLV
ING80386 SX
2
–25
Valid Combinations lists configurations
planned to be supported in volume for this
device. Consult the local AMD sales office
to confirm availability of specific valid
combinations and to check on newly
released combinations.
–33
–25
–25
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
BLOCK DIAGRAM
Paging Unit
Bus Control
3-Input
Adder
Adder
Request
Prioritizer
Descriptor
Registers
Effective Address Bus
32
Register
File
ALU
Control
Decode
and
Sequencing
Instruction
Decoder
Control
ROM
3-Decoded
Instruction
Queue
Control
Instruction
Predecode
ALU
Code Fetch/Page Table Fetch
Linear Address Bus
Displacement Bus
Multiply/
Divide
Status
Flags
Internal Control Bus
Page
Cache
Control
and
Attribute
PLA
Limit and
Attribute
PLA
Protection
Test Unit
Barrel
Shifter,
Adder
32
Physical Address Bus
25
32
Prefetcher/
Limit
Checker
Code
Stream
32 Bit
Address
Driver
Pipeline/
Bus Size
Control
32
HOLD, INTR,
NMI, ERROR,
BUSY, RESET,
HLDA, FLT,
SMI*, IIBEN*
Control
Effective Address Bus
Segmentation Unit
MUX/
Transceivers
BHE, BLE,
A23-A1
M/IO, D/C,
W/R, LOCK,
ADS, NA,
READY,
SMIADS*,
SMIRDY*
D15-D0
16-Byte
Code
Queue
Instruction
Prefetch
Dedicated ALU Bus
32
* – On Am386SXLV only
FUNCTIONAL DESCRIPTION
True Static Operation
(Am386SXL/SXLV Only)
The Am386SXL/SXLV microprocessor incorporates a
true static design. Unlike dynamic circuit design, the
Am386SXL/SXLV device eliminates the minimum operating frequency restriction. It may be clocked from its
maximum speed all the way down to 0 MHz (DC). System designers can use this feature to design portable
applications with long battery life.
Standby Mode (Am386SXL/SXLV Only)
The true static design of the Am386SXL/SXLV microprocessor allows for a Standby Mode. At any operating
speed, the microprocessor will retain its state (i.e., the
contents of all its registers). By shutting off the clock
completely, the device enters Standby Mode. Since
power consumption is proportional to clock frequency,
operating power consumption is reduced as the frequency is lowered. In Standby Mode, typical current
draw is reduced to less than 20 microamps at DC. Not
only does this feature save battery life, but it also sim-
plifies the design of power-conscious portable applications in the following ways.
■ Eliminates the need for software in BIOS to save
and restore the contents of registers.
■ Allows simpler circuitry to control stopping of the
clock since the system does not need to know
the state of the processor.
Lower Operating Icc
(Am386SXL/SXLV Only)
True static design also allows lower operating Icc when
operating at any speed.
Performance on Demand
(Am386SXL/SXLV Only)
The Am386SXL/SXLV microprocessor retains its state
at any speed from 0 MHz (DC) to its maximum operating speed. With this feature, system designers may
vary the operating speed of the system to extend the
battery life in portable systems.
Am386SX/SXL/SXLV Microprocessors Data Sheet
3
F I N A L
For example, the system could operate at low speeds
during inactivity or polling operations. However, upon
interrupt, the system clock can be increased up to its
maximum speed. After a user-defined time-out period,
the system can be returned to a low (or 0 MHz) operating speed without losing its state. This design maximizes battery life while achieving optimal performance.
to the SMM code is executed. This Real mode code
can perform its system management function and then
resume execution of the normal system software by executing an RES3 instruction which will reload the saved
processor state and continue execution in the main
system memory space. See Figure 1 for a general flowchart of an SMM operation.
Benefits of Lower Operating Voltage
(Am386SXLV Only)
CPU Interface—Pin Functions
The Am386SXLV microprocessor has an operating
voltage range of 3.0 V to 5.5 V. Low voltage allows for
lower operating power consumption, longer battery life,
and/or smaller batteries for portable applications.
Because power is proportional to the square of the voltage, reduction of the supply voltage from 5.0 V to 3.3 V
reduces power consumption by 56%. This directly
translates to a doubling of battery life for portable applications. Lower power consumption can also be used to
reduce the size and weight of the battery. Thus, 3.3-V
designs facilitate a reduction in the form factor.
A lower operating voltage results in a reduction of I/O
voltage swings. This reduces noise generation and
provides a less hostile environment for board design.
Lower operating voltage also reduces electromagnetic
radiation noise and makes FCC approval easier to obtain.
SMM—System Management Mode
(Am386SXLV Only)
The Am386SXLV microprocessor has a System Management Mode (SMM) for system and power management. This mode consists of two features: System
Management Interrupt (SMI) and I/O instruction break.
SMI—System Management Interrupt
SMI is implemented by using special bus interface
pins. This interrupt method can be used to perform system management functions such as power management independent of processor operating mode (Real,
Protected, or Virtual 8086 modes).
SMI can also be invoked in software. This allows system software to communicate with SMI power management code. In addition, the UMOV instruction allows
data transfers between SMI and normal system memory spaces.
Activating the SMI pin invokes a sequence that saves
the operating state of the processor into a separate
SMM memory space, independent of the main system
memory. After the state is saved, the processor is
forced into Real mode and begins execution at address
FFFFF0h in the SMM memory space where a far jump
4
The CPU interface for SMM consists of three pins dedicated to the SMI function. One pin, SMI, is the interrupt
input. The other two pins, SMIADS and SMIRDY, provide the control signals necessary for the separate
SMM mode memory space.
SMI sampled
active (Low)
Current instruction
finishes execution,
normal ADS goes inactive
CPU saves state to separate SMM memory space,
starting at address 60000h
CPU enters Real Mode,
starts code fetches at
location FFFFF0h in
SMM memory space
Real Mode SMM interrupt
handler code execution (after FAR JUMP)
Restore saved state from
60000h with RES3 (0F 07)
opcode sequence
Normal code
execution
resumes
16305C–002
Figure 1. SMM Flow
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
Description of SMM Operation
(Am386SXLV Only)
The execution of a System Management Interrupt has
four distinct phases: the initiation of the interrupt via
SMI, a processor state save, execution of the SMM interrupt code, and a processor state restore (to resume
normal operation).
Interrupt Initiation
A System Management Interrupt is initiated by the driving of a synchronous, active Low pulse on the SMI pin
until the first SMIADS is asserted. This pulse period will
ensure recognition of the interrupt. The CPU drives the
SMI pin active after the completion of the current operation (active bus cycle, instruction execution, or both).
The active drive of the pin by the CPU is released at the
end of the interrupt routine following the last register
read of the saved state. The CPU drives SMI High for
two CLK2 cycles prior to releasing the drive of SMI.
Both INTR and NMI are disabled upon entry into SMM.
The SMM code can be located anywhere within the
1-Mbyte Real mode address space, except for where
the processor state is saved. I/O cycles, as a result of
the IN, OUT, INS, and OUTS instructions, will go to the
normal address space, utilizing the normal ADS and
READY bus interface signals. This facilitates power
management code manipulating system hardware registers as needed through the standard I/O subsystem;
a separate I/O space is not implemented.
Processor State Restore
(Resuming Normal Execution)
Returning to normal code execution in the main system
memory, including restoring the processor operating
mode, is accomplished by executing a special code sequence. This code invokes a restore CPU state operation that reloads the CPU registers from the saved data
in the RAM controlled by SMIADS and SMIRDY.
While the CPU is in SMM, a bus hold request via the
HOLD pin is granted. The HLDA pin goes active after
bus release and the SMIADS pin floats along with the
other pins that normally float during a bus hold cycle.
SMI does not float during a Bus Hold cycle.
The ES:EDI register pair must point to the physical address of the processor save state (6000h). In Real
mode the address is calculated as ES•16 + EDI offset.
The saved state should not cross a 64K boundary. The
RES3 instruction (0F 07) should be executed to start
the restore state operation. After completion of the restore state operation, the SMI pin will be deactivated by
the CPU and normal code execution will continue at the
point where it left off before the SMI occurred. There
are 114 data transfer cycles in the restore operation.
Processor State Save
Software Features (Am386SXLV Only)
The first set of SMM bus transfer cycles after the CPU’s
recognition of an active SMI is the processor saving its
state to an external RAM array in a separate address
space from main system memory. This is accomplished by using the SMIADS and SMIRDY pins for initiation and termination of bus cycles, instead of the
ADS and READY pins. The 24-bit addresses to which
the CPU saves its state are 60000h–600CBh and
60100h–60127h. These are fixed address locations for
each register saved.
Several features of the SMI function provide support for
special operations during the execution of the system’s
software. These features involve the execution of reserved opcodes to induce specific SMI-related operations.
An SMI cannot be masked off by the CPU, and it will always be recognized by the CPU, regardless of operating modes. This includes the Real, Protected, and Virtual-8086 modes of the processor.
To ensure valid operation, pipelining must be disabled
while the processor is in SMM. There are 114 data
transfer cycles.
SMI Code Execution
After the processor state is saved to the separate SMM
memory space, the execution of the SMM interrupt routine code begins. The processor enters Real mode,
sets most of the register values to “reset” values (those
values normally seen after a CPU reset), and begins
fetching code from address FFFFF0h in the separate
SMM memory space. Normally, the first thing the interrupt routine code does is a FAR JUMP to the Real
mode entry point for the SMM interrupt routine, which
is also in SMM memory space.
Software SMI Generation
Besides hardware initiation of the SMI via the SMI pin,
there is also a software-induced SMI mechanism. Generating a soft SMI involves setting a control bit (Bit 12)
in the Debug Control Register (DR7) and executing an
SMI instruction (opcode F1h).
The functional sequence of the software-based SMI is
identical to the hardware-based SMI with the exception
that the SMI pin is not initially driven active by an external source. Upon execution of a soft SMI opcode, the
SMI pin is driven active (Low) by the processor before
the save state operation begins.
Memory Transfers to Main System Memory
While executing an SMI routine, the interrupt code can
initiate memory data reads and writes to the main system memory using the normal ADS and READY pins.
This initiation is accomplished by using reserved opcodes that are special forms of the MOV instruction
(called UMOV). The UMOV opcodes can move byte,
Am386SX/SXL/SXLV Microprocessors Data Sheet
5
F I N A L
word, or double word register operands to or from main
system memory. Multiple data transfers using the normal ADS and READY pins will occur if the operands
are misaligned relative to the effective address used.
The UMOV opcodes are 0F 10h, 0F 11h, 0F 12h, and
0F 13h. The UMOV instruction can use any of the 386
addressing modes, as specified in the ModR/M byte of
the opcode. Note that the 16- and 32-bit versions are
the same opcodes with the exception of the 66h operand size prefix.
I/O Instruction Break (Am386SXLV Only)
The Am386SXLV microprocessor has an I/O instruction break feature that allows the system logic to implement I/O trapping for peripheral devices. To enable the
I/O Instruction break feature, IIBEN must first be asserted active Low. On detecting an I/O instruction, the
processor prevents the execution unit from executing
further instructions until READY is driven active Low by
the system. Once READY is driven active, the execution unit either immediately responds to any active interrupt request or continues executing instructions following the I/O instruction that caused the break.
The I/O instruction break feature can be used to allow
system logic to implement I/O trapping for peripheral
devices. On sensing an I/O instruction, the system
drives the SMI pin active before driving READY active.
This ensures that the interrupt service routine is executed immediately following the I/O instruction that
caused the break. (If the I/O instruction break feature is
not enabled via IIBEN, several instructions could execute before the SMI service routine is executed.)
The SMI service routine can access the peripheral for
which SMI was asserted and modify its state.The SMI
6
service routine normally returns to the instruction following the I/O instruction that caused the break. By
modifying the saved state instruction pointer, the routine can choose to return to the I/O instruction that
caused the break and re-execute that instruction. The
default is to return to the following instruction (except
for REP I/O string instruction). To re-execute the I/O instruction that caused the break, the SMI service routine
must copy the I/O instruction pointer over the default
pointer. This feature is particularly useful when an application program requests an access to a peripheral
that has been powered down. The SMI service routine
can restore power to the peripheral and initiate a re-execution sequence transparent to the application program. This re-execution feature should only be used if
the SMI is in response to an I/O trap with IIBEN active.
Note that the I/O instruction break feature is not enabled for memory mapped I/O devices or for coprocessor bus cycles even if IIBEN is active.
I/O Instruction Break Timing
The I/O Instruction Break feature requires that SMI be
sampled active (Low) by the processor at least three
CLK2 edges before the CLK2 edge that ends the I/O
cycle with an active READY signal. This timing applies
for both pipelined and non-pipelined cycles. If this timing constraint is not met, additional instructions may be
executed by the internal execution unit prior to entering
SMM. Depending on the state of the prefetch queue at
the time the SMI is asserted, instruction fetch cycles
may occur on the normal ADS interface before the
SMM save state process begins with the assertion of
SMIADS. However, this fetched code will not be executed.
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
VSS
A21
76
A22
VSS
78
77
80
79
82
81
D15
A23
VCC
D13
D14
84
83
85
D11
D12
VSS
87
86
D10
D8
D9
89
88
D7
VCC
94
91
90
D5
D6
96
95
93
92
VCC
D3
D4
98
97
D2
VSS
100
99
D1
CONNECTION DIAGRAM
100-Lead Plastic Quad Flat Pack (PQFP) Package—Top Side View
D0
1
75
A20
VSS
HLDA
HOLD
VSS
NA
2
3
4
A19
A18
A17
VCC
A16
READY
VCC
7
8
74
73
72
71
70
69
68
67
66
65
64
63
A14
A13
VSS
62
61
60
59
58
A12
A11
A10
A9
A8
57
56
VCC
A7
55
54
53
52
51
A6
A5
A4
VSS
9
10
11
12
13
14
CLK2
ADS
BLE
A1
BHE
15
16
17
18
19
NC
VCC
VSS
M/IO
20
21
22
VCC
VSS
VSS
A15
45
46
47
48
49
50
A3
A2
*SMI
NC
NC
NC
NC
VCC
VSS
VSS
40
41
42
43
44
INTR
VSS
VCC
37
38
39
ERROR
PEREQ
NMI
VCC
RESET
BUSY
VSS
LOCK
NC
FLT
*IIBEN
*SMIRDY
*SMIADS
VCC
34
35
36
23
24
25
26
D/C
W/R
Top Side View
27
28
29
30
31
32
33
VCC
VCC
VSS
VSS
VSS
5
6
Notes:
Pin 1 is marked for orientation
NC = Not connected; connection of an NC pin may cause a malfunction or incompatibility
with future shippings of the Am386SX/SXL/SXLV microprocessors
* = On Am386SXLV only; NC on Am386SX/SXL
Am386SX/SXL/SXLV Microprocessors Data Sheet
7
F I N A L
44
45
46
47
48
49
50
SMI*
NC
NC
NC
NC
VCC
VSS
VSS
ERROR
PEREQ
NMI
VCC
36
37
38
39
40
41
42
43
INTR
VSS
VCC
RESET
BUSY
VSS
33
34
35
29
30
31
32
27
28
LOCK
NC
FLT
IIBEN*
SMIRDY*
SMIADS*
VCC
26
CONNECTION DIAGRAM
100-Lead Plastic Quad Flat Pack (PQFP) Package—Pin Side View
W/R
D/C
25
24
51
52
A2
A3
M/IO
VSS
VCC
NC
23
22
21
20
19
53
54
55
56
57
A4
A5
A6
18
58
59
60
61
62
63
64
A8
A9
BHE
A1
BLE
ADS
CLK2
VSS
VSS
VSS
VSS
VCC
VCC
VCC
READY
NA
VSS
HOLD
HLDA
VSS
Pin Side View
65
66
11
10
9
8
7
67
68
69
70
71
6
5
4
3
72
73
2
1
74
75
Notes:
Pin 1 is marked for orientation
NC = Not connected; connection of an NC pin may cause a malfunction or incompatibility
with future shippings of the Am386SX/SXL/SXLV microprocessors
* = On Am386SXLV only; NC on Am386SX/SXL
8
Am386SX/SXL/SXLV Microprocessors Data Sheet
A21
A22
VSS
VSS
A23
D14
D15
D13
D12
VSS
VCC
D9
D10
D11
D8
D6
D7
VCC
D4
D5
D3
D1
D2
VSS
VCC
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
D0
17
16
15
14
13
12
A7
VCC
A10
A11
A12
VSS
A13
A14
A15
VSS
VSS
VCC
A16
VCC
A17
A18
A19
A20
F I N A L
PIN DESIGNATION TABLE (Sorted by Functional Grouping)
Address
Pin Name
Data
Pin No.
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
18
51
52
53
54
55
56
58
59
60
61
62
A13
A14
A15
A16
A17
A18
A19
A20
A21
A22
A23
64
65
66
70
72
73
74
75
76
79
80
Pin Name
Control
VSS
VCC
NC
Pin No.
Pin Name
Pin No.
Pin No.
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
1
100
99
96
95
94
93
92
90
89
88
87
16
19
17
34
15
24
36
28
3
4
29
40
20
27
44
45
46
47
D12
D13
D14
D15
86
83
82
81
ADS
BHE
BLE
BUSY
CLK2
D/C
ERROR
FLT
HLDA
HOLD
IIBEN*
INTR
LOCK
M/IO
NA
NMI
PEREQ
READY
RESET
SMI*
SMIADS*
SMIRDY*
W/R
Pin No. Pin No.
26
23
6
38
37
7
33
43
31
30
25
8
9
10
21
32
39
42
48
57
69
71
84
2
5
11
12
13
14
22
35
41
49
50
63
91
97
67
68
77
78
85
98
* On Am386SXLV only; NC on Am386SX/SXL
PIN DESIGNATION TABLE (Sorted by Pin Number)
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Pin Name
D0
VSS
HLDA
HOLD
VSS
NA
READY
VCC
VCC
VCC
VSS
VSS
VSS
VSS
CLK2
ADS
BLE
A1
BHE
NC
Pin No.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Pin Name
VCC
VSS
M/IO
D/C
W/R
LOCK
NC
FLT
IIBEN*
SMIRDY*
SMIADS*
VCC
RESET
BUSY
VSS
ERROR
PEREQ
NMI
VCC
INTR
Pin No.
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Pin Name
VSS
VCC
SMI*
NC
NC
NC
NC
VCC
VSS
VSS
A2
A3
A4
A5
A6
A7
VCC
A8
A9
A10
Pin No.
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
Pin Name
A11
A12
VSS
A13
A14
A15
VSS
VSS
VCC
A16
VCC
A17
A18
A19
A20
A21
VSS
VSS
A22
A23
Pin No.
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
Pin Name
D15
D14
D13
VCC
VSS
D12
D11
D10
D9
D8
VCC
D7
D6
D5
D4
D3
VCC
VSS
D2
D1
* On Am386SXLV only; NC on Am386SX/SXL
Am386SX/SXL/SXLV Microprocessors Data Sheet
9
F I N A L
PIN DESCRIPTIONS
A23–A1
Address Bus (Outputs)
HOLD
Bus Hold Request (Active High; Input)
Outputs physical memory or port I/O addresses.
Input allows another bus master to request control of
the local bus.
ADS
Address Status (Active Low; Output)
IIBEN (Am386SXLV Only)
I/O Instruction Break Enable (Active Low; Input)
Indicates that a valid bus cycle definition and address
(W/R, D/C, M/IO, BHE, BLE, and A23–A1) are being
driven at the Am386SX/SXL/SXLV microprocessor
pins. Bus cycles initiated by ADS must be terminated
by READY.
Enables the I/O instruction break feature. IIBEN has a
dynamic internal pull-up resistor. The IIBEN pull-up is
active during RESET and whenever the signal is not
driven active Low by the system.
BHE, BLE
Byte Enables (Active Low; Outputs)
INTR
Interrupt Request (Active High; Input)
Indicate which data bytes of the data bus take part in a
bus cycle.
A maskable input that signals the Am386SX/SXL/
SXLV microprocessor to suspend execution of the current program and execute an interrupt acknowledge
function.
BUSY
Busy (Active Low; Input)
Signals a busy condition from a processor extension.
BUSY has an internal pull-up resistor.
LOCK
Bus Lock (Active Low; Output)
CLK2
CLK2 (Input)
A bus cycle definition pin that indicates that other system bus masters are not to gain control of the system
bus while it is active.
Provides the fundamental timing for the Am386SX/
SXL/SXLV microprocessor.
D15–D0
Data Bus (Inputs/Outputs)
A bus cycle definition pin that distinguishes memory cycles from input/output cycles.
Inputs data during memory, I/O, and interrupt acknowledge read cycles; outputs data during memory and I/O
write cycles.
NA
Next Address (Active Low; Input)
Used to request address pipelining.
D/C
Data/Control (Output)
A bus cycle definition pin that distinguishes data cycles, either memory or I/O, from control cycles which
are interrupt acknowledge, halt, and code fetch.
ERROR
Error (Active Low; Input)
Signals an error condition from a processor extension.
ERROR has an internal pull-up resistor.
FLT
Float (Active Low; Input)
An input which forces all bidirectional and output signals, including HLDA, to the three-state condition. FLT
has an internal pull-up resistor. The pin, if not used,
should be disconnected.
HLDA
Bus Hold Acknowledge (Active High; Output)
Output indicates that the Am386SX/SXL/SXLV microprocessor has surrendered control of its logical bus to
another bus master.
10
M/IO
Memory/IO (Output)
NC
No Connect
Should always be left unconnected. Connection of an
NC pin may cause the processor to malfunction or be
incompatible with future steppings of the Am386SX/
SXL/SXLV microprocessor.
NMI
Non-Maskable Interrupt Request
(Active High; Input)
A non-maskable input that signals to the Am386SX/
SXL/SXLV microprocessor to suspend execution of the
current program and execute an interrupt acknowledge
function.
PEREQ
Processor Extension Request (Active High; Input)
Indicates that the processor has data to be transferred
by the Am386SX/SXL/SXLV microprocessor. PEREQ
has an internal pull-down resistor.
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
READY
Bus Ready (Active Low; Input)
Terminates the bus cycle initiated by ADS.
croprocessor pins while in the System Management
mode. Bus cycles initiated by SMIADS must be terminated by SMIRDY.
RESET
Reset (Active High; Input)
SMIRDY (Am386SXLV Only)
SMI Ready (Active Low; Input)
Suspends any operation in progress and places the
Am386SX/SXL/SXLV microprocessor in a known reset
state.
This input terminates the current bus cycle to the SMM
mode address space in the same manner the READY
pin does for the normal mode address space. SMIRDY
has an internal pull-up resistor. READY and SMIRDY
must not be tied together.
SMI (Am386SXLV Only)
System Management Interrupt (Active Low; I/O)
A non-maskable interrupt pin that signals to the
Am386SXLV microprocessor to suspend execution
and enter System Management Mode. SMI has an internal pull-up resistor. SMI has a dynamic internal
pull-up resistor that is disabled when the processor is
in SMM. SMI is not three-stated during Hold Acknowledge bus cycles.
SMIADS (Am386SXLV Only)
SMI Address Status (Active Low; Output)
When active, this pin indicates that a valid bus cycle
definition and address (W/R, D/C, M/IO, BHE, BLE,
and A23–A1) are being driven at the Am386SXLV mi-
VCC
System Power (Input)
Provides the 5 V nominal DC supply input.
VSS
System Ground (Input)
Provides the 0-V connection from which all inputs and
outputs are measured.
W/R
Write/Read (Output)
A bus cycle definition pin that distinguishes write cycles
from read cycles.
LOGIC SYMBOL
CLK2
2X Clock
23
D15–D0
16
A23–A1
Address
Bus
FLT
2
Data Bus
Float
BLE, BHE
RESET
NMI
Interrupt
Control
INTR
Bus
Cycle
Control
ADS
NA
Am386SXLV
Microprocessor
READY
PEREQ
Bus
Cycle
Definition
W/R
BUSY
D/C
ERROR
M/IO
LOCK
SMI
SMIADS
SMIRDY
IIBEN
HOLD
*On Am386SXLV only
Math
Coprocessor
Control
System
Management
Mode
Control*
HLDA
Bus Arbitration
Control
Am386SX/SXL/SXLV Microprocessors Data Sheet
16305C–003
11
F I N A L
ABSOLUTE MAXIMUM RATINGS
OPERATING RANGES
Storage Temperature ....................... –65°C to +150°C
Ambient Temperature Under Bias .... –65°C to +125°C
Supply Voltage with respect to Vss..... –0.5 V to +7.0 V
Voltage on Other Pins................ –0.5 V to (Vcc +0.5) V
Stresses above those listed may cause permanent
damage to the device. Functionality at or above these
limits is not implied. Exposure to ABSOLUTE MAXIMUM RATING conditions for extended periods may affect device reliability.
Operating ranges define those limits between which
the functionality of the device is guaranteed.
DC CHARACTERISTICS over COMMERCIAL operating ranges for 25 MHz Am386SXLV
Vcc =3.0 V to 3.6 V; TCASE =0°C to +100°C
Final
Symbol
VIL
Parameter Description
Input Low Voltage
VIH
Input High Voltage
VILC
CLK2 Input Low Voltage
VIHC
CLK2 Input High Voltage
VOL
Output Low Voltage
IOL = 0.5 mA: A23–A1, D15–D0
IOL = 0.5 mA: BHE, BLE, W/R, D/C, SMIADS,
M/IO, LOCK, ADS, HLDA, SMI
IOL = 2 mA: A23–A1, D15–D0
IOL = 2.5 mA: BHE, BLE, W/R, D/C, SMIADS,
LOCK, ADS, M/IO, HLDA, SMI
VOH
ILI
Output High Voltage
IOH = 0.1 mA: A23–A1, D15–D0
IOH = 0.1 mA: BHE, BLE, W/R, D/C, SMIADS,
LOCK, ADS, M/IO, HLDA, SMI
IOH = 0.5 mA: A23–A1, D15–D0
IOH = 0.5 mA: BHE, BLE, W/R, D/C, SMIADS,
LOCK, ADS, M/IO, HLDA, SMI
Input Leakage Current (All pins except
PEREQ, BUSY, ERROR, SMI, SMIRDY,
FLT, IIBEN)
Notes
(Note 1)
Min
–0.3
Max
+0.8
Unit
V
2.0
VCC +0.3
V
(Note 1)
–0.3
+0.8
V
2.4
VCC +0.3
V
0.2
0.2
V
V
0.45
0.45
V
V
(Note 5)
(Note 5)
(Note 6)
VCC –0.2
VCC–0.2
V
V
VCC–0.45
VCC –0.45
V
V
0 V ≤ VIN ≤ VCC
(Note 7)
±10
µA
IIH
Input Leakage Current
(PEREQ pin)
VIH = VCC –0.1 V
VIH = 2.4 V (Note 2)
300
200
µA
µA
IIL
Input Leakage Current
(BUSY, ERROR, SMI, SMIRDY, FLT, IIBEN)
VIL = 0.1 V
VIL = 0.45 V (Note 3)
–300
–200
µA
µA
ILO
Output Leakage Current
Supply Current (Note 8)
CLK2 = 50 MHz: Oper. Freq. 25 MHz
0.1 V ≤ VOUT ≤ VCC
VCC
= 3.3 V
ICC Typ = 95
+15
VCC = 3.6 V
115
µA
ICCSB
Standby Current (Note 8)
ICCSB Typ = 10µA
150
µA
CIN
Input or I/O Capacitance
FC = 1 MHz (Note 4)
10
pF
COUT
Output Capacitance
FC = 1 MHz (Note 4)
12
pF
CCLK
CLK2 Capacitance
FC = 1 MHz (Note 4)
20
pF
ICC
Notes:
1.
2.
3.
4.
5.
6.
7.
8.
12
The Min value, –0.3, is not 100% tested.
PEREQ input has an internal pull-down resistor.
BUSY, ERROR , FLT, SMI, IIBEN, and SMIRDY inputs each have an internal pull-up resistor.
Not 100% tested.
Outputs are CMOS and will pull rail-to-rail if the load is not resistive.
VOH SMI only valid on SMI output when exiting SMM for two CLK2 periods.
SMI and IIBEN leakage Low will be ILI when pull-up is inactive and IIL when pull-up is active.
Inputs at rails (VCC or VSS).
Am386SX/SXL/SXLV Microprocessors Data Sheet
mA
F I N A L
ABSOLUTE MAXIMUM RATINGS
OPERATING RANGES
Storage Temperature ....................... –65°C to +150°C
Ambient Temperature under Bias .... –65°C to +125°C
Supply Voltage with respect to VSS .... –0.5 V to +7.0 V
Voltage on Other Pins................–0.5 V to (Vcc +0.5) V
Stresses above those listed may cause permanent
damage to the device. Functionality at or above these
limits is not implied. Exposure to ABSOLUTE MAXIMUM RATING conditions for extended periods may affect device reliability.
Operating ranges define those limits between which
the functionality of the device is guaranteed.
DC CHARACTERISTICS over COMMERCIAL and INDUSTRIAL operating ranges
25 and 33 MHz: Vcc = 5 V ± 10%; TCASE = 0°C to +100°C (commercial); TCASE = –40°C to +100°C (industrial)
40 MHz: Vcc = 5 V ± 5%; TCASE = 0°C to +100°C
Final
Symbol
VIL
Parameter Description
Input Low Voltage
VIH
Input High Voltage
VILC
CLK2 Input Low Voltage
VIHC
CLK2 Input High Voltage
VOL
Output Low Voltage
IOL = 4 mA: A23–A1, D15–D0
IOL = 5 mA: BHE, BLE,W/R, D/C, SMIADS*,
M/IO, LOCK, ADS, HLDA, SMI*
Output High Voltage
IOH = 1.0 mA: A23–A1, D15–D0
IOH = 0.2 mA: A23–A1, D15–D0
IOH = 0.9 mA: BHE, BLE, W/R, D/C, SMIADS*,
LOCK, ADS, M/IO, HLDA, SMI*
IOH = 0.18 mA: BHE, BLE, W/R, D/C, SMIADS*,
LOCK, ADS, M/IO, HLDA, SMI*
VOH
Notes
(Note 1)
(Note 1)
Min
–0.3
Max
+0.8
Unit
V
2.0
VCC +0.3
V
–0.3
+0.8
V
2.7
VCC +0.3
V
0.45
0.45
V
V
(Note 5)
(Note 5)
(Note 6*)
2.4
VCC –0.5
2.4
V
V
V
VCC –0.5
V
Input Leakage Current (All pins except
PEREQ, BUSY, ERROR, SMI*, SMIRDY*,
FLT, and IIBEN*)
0 V ≤ VIN ≤ VCC
(Note 7)
±15
µA
IIH
Input Leakage Current (PEREQ pin)
VIH = 2.4 V (Note 2)
200
µA
IIL
Input Leakage Current
(BUSY, ERROR, SMI*, SMIRDY*, FLT, IIBEN*)
VIL = 0.45 V (Note 3)
–400
µA
ILO
Output Leakage Current: Am386SX/SXL
Am386SXLV
0.1 V ≤ VOUT ≤ VCC
0.45 V ≤ VOUT ≤ VCC
±15
±15
µA
µA
ICC
ICCSB
Supply Current (Note 8)
CLK2 = 50 MHz: Oper. Freq. 25 MHz
CLK2 = 66 MHz: Oper. Freq. 33 MHz
CLK2 = 80 MHz: Oper. Freq. 40 MHz
Standby Current (Note 8)
VCC Typ = 5.0 V
ICC Typ = 160
ICC Typ = 210
ICC Typ = 255
ICCSB Typ = 20 µA
VCC = 5.5
190
245
295
150
V
mA
mA
mA
µA
CIN
Input or I/O Capacitance
FC = 1 MHz (Note 4)
10
pF
COUT
Output or I/O Capacitance
FC = 1 MHz (Note 4)
12
pF
CCLK
CLK2 Capacitance
FC = 1 MHz (Note 4)
20
pF
ILI
Notes:
* On Am386SXLV only
1. The Min value, –0.3, is not 100% tested.
2. PEREQ input has an internal pull-down resistor.
3. BUSY, ERROR, FLT, SMI*, IIBEN*, and SMIRDY* inputs each have an internal pull-up resistor.
4. Not 100% tested.
5. Outputs are CMOS and will pull rail-to-rail if the load is not resistive.
6. VOH SMI only valid on SMI output when exiting SMM for two CLK2 periods (on Am386SXLV only).
7. SMI and IIBEN leakage Low will be ILI when pull-up is inactive and IIL when pull-up is active (on Am386SXLV only).
8. Inputs at rails (VCC or VSS), outputs unloaded, PEREQ Low, ERROR High, BUSY High, and FLT High.
Am386SX/SXL/SXLV Microprocessors Data Sheet
13
F I N A L
SWITCHING CHARACTERISTICS
The switching characteristics given consist of output
delays, input setup requirements, and input hold requirements. All switching characteristics are relative to
the CLK2 rising edge crossing the 2.0-V level.
Switching characteristic measurement is defined in
Figure 2. Inputs must be driven to the voltage levels indicated by Figure 2 when switching characteristics are
measured. Output delays are specified with minimum
and maximum limits measured, as shown. The minimum delay times are hold times provided to external
circuitry. Input setup and hold times are specified as
minimums, defining the smallest acceptable sampling
window. Within the sampling window, a synchronous
input signal must be stable for correct operation.
Outputs ADS, W/R, D/C, M/IO, LOCK, BHE, BLE,
A23–A1, HLDA, and SMIADS* only change at the beginning of phase one. D15–D0 and SMI* write cycles
only change at the beginning of phase two. The
READY, HOLD, BUSY, ERROR, PEREQ, FLT, D15–
D0, IIBEN*, and SMIRDY* read cycles inputs are sampled at the beginning of phase one. The NA, INTR,
NMI, and SMI* inputs are sampled at the beginning of
phase two.
* – On Am386SXLV only; NC on Am386SX/SXL
Tx
φ2
φ1
CLK2
2V
A
(A23–A1, BHE, BLE,
ADS, M/IO, D/C,
W/R, LOCK, HLDA,
SMIADS*)
B
Min
Valid VT
Output n
Max
VT
Valid
Output n+1
A
B
Min
Valid VT
Output n
(D15–D0, SMI*)
C
(NA, INTR, NMI, SMI*)
VT
Max
VT
Valid
Output n+1
D
Valid
Input
VT
C
(READY, HOLD,
FLT, ERROR, BUSY,
PEREQ, D15–D0,
IIBEN*, SMIRDY*)
VT
D
Valid
Input
VT
Legend: A–Maximum Output Delay Characteristic
B–Minimum Output Delay Characteristic
C–Minimum Input Setup Characteristic
D–Minimum Input Hold Characteristic
Notes:
1. Input waveforms have tr ≤ 2.0 ns from 0.8 V–2.0 V (on Am386SXLV only).
2. On Am386SX/SXL, VT = 1.5; on Am386SXLV, VT = 1.0 V for VCC ≤ 3.6 V and 1.5 V for VCC > 3.6 V.
3. * = On Am386SXLV only.
Figure 2. Drive Levels and Measurement Points for Switching Characteristics
14
Am386SX/SXL/SXLV Microprocessors Data Sheet
16305C–003
F I N A L
SWITCHING CHARACTERISTICS over COMMERCIAL and INDUSTRIAL operating ranges
at 25 MHz
VCC = 5.0 V ± 10%; TCASE = 0°C to +100°C (Commercial); TCASE = –40°C to +100°C (Industrial)
VCC = 3.0 V–5.5 V; TCASE = 0°C to +100°C (Am386SXLV only)
Symbol
1
2
2a
2b
3
3a
3b
4
5
6
7
8
9
10
10s
11
11s
12
12a
13
14
14f
Parameter Description
Operating Frequency: Am386SX CPU
Am386SXL/SXLV CPU
CLK2 Period
CLK2 High Time:
Am386SXLV CPU
CLK2 High Time:
Am386SX/SXL CPU
CLK2 High Time:
Am386SX/SXL CPU
CLK2 Low Time:
Am386SXLV CPU
CLK2 Low Time:
Am386SX/SXL CPU
CLK2 Low Time:
Am386SX/SXL CPU
CLK2 Fall Time:
Am386SX/SXL CPU
Am386SXLV CPU
CLK2 Rise Time:
Am386SX/SXL CPU
Am386SXLV CPU
A23–A1 Valid Delay
A23–A1 Float Delay
BHE, BLE, LOCK Valid Delay
BHE, BLE, LOCK Float Delay
M/IO, D/C, W/R, ADS Valid Delay
SMIADS Valid Delay
W/R, M/IO, D/C, ADS Float Delay
SMIADS Float Delay
D15–D0 Write Data Valid Delay
D15–D0 Write Data Hold Time
D15–D0 Write Data Float Delay
HLDA Valid Delay
HLDA Float Delay:
Am386SX/SXL
Am386SXLV
NA Setup Time
NA Hold Time
READY Setup Time
SMIRDY Setup Time
READY Hold Time
SMIRDY Hold Time
D15–D0 Read Data Setup Time
D15–D0 Read Data Hold Time
HOLD Setup Time
HOLD Hold Time
RESET Setup Time
RESET Hold Time
NMI, INTR Setup Time
SMI Setup Time
NMI, INTR Hold Time
SMI Hold Time
PEREQ, ERROR, BUSY, FLT, IIBEN5 Setup Time
PEREQ, ERROR, BUSY, FLT, IIBEN5 Hold Time
SMI Valid Delay
SMI Float Delay
Ref.
Figures
Notes
Half CLK2 freq.
Half CLK2 freq.
at VIHC
at 2 V
at (VCC–0.8 V)
at 0.8 V
at 2 V
at 0.8 V
(VCC–0.8 V) to 0.8 V
2.4 V to 0.8 V
0.8 V to 2.4 V
0.8 V to (VCC–0.8 V)
CL = 50 pF
(Note 3)
(Note 3)
(Note 3)
(Note 3)
(Note 1)
CL = 50 pF
(Note 1)
CL = 50 pF
CL = 50 pF
(Note 5)
(Note 1)
(Notes 1, 5)
CL = 50 pF
CL = 50 pF
(Note 1)
CL = 50 pF
(Notes 1, 4)
3, 4
3
4
4
3
4
4
4
3
4
3
8
15
8
15
8
8
15, 18
15
8, 9
10
15
8
15, 16
Final
Min Max
2
25
0
25
20
4
7
4
5
7
5
4
4
4
4
4
4
4
4
7
2
4
4
4
4
5
3
9
9
4
4
7
5
9
3
8
3
6
6
6
4
6
5
4
4
Unit
MHz
ns
ns
ns
ns
ns
ns
ns
7
ns
7
ns
17
30
17
30
17
25
30
30
23
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
22
22
22
30
ns
15
7
ns
7
ns
16
19
7
ns
19s
(Note 5)
7
ns
7
ns
20
20s
(Note 5)
7
ns
21
7
ns
22
7
ns
23
7
ns
24
7
ns
25
17
ns
26
17
ns
27
(Note 2)
7
ns
(Note 5)
7
ns
27s
28
(Note 2)
7
ns
(Note 5)
7
ns
28s
29
(Note 2)
7
ns
30
(Note 2)
7
ns
(Note 5)
8, 15
22
ns
31
32
(Notes 1, 4, 5)
16
30
ns
Notes:
1. Float condition occurs when maximum output current becomes less than ILO in magnitude. Float delay is not 100% tested.
2. These inputs are allowed to be asynchronous to CLK2. The setup and hold specifications are given for testing purposes, to
assure recognition within a specific CLK2 period.
3. Rise and Fall times are not tested. They are guaranteed by design characterization.
4. Only during FLT assertion.
5. On Am386SXLV only.
Am386SX/SXL/SXLV Microprocessors Data Sheet
15
F I N A L
SWITCHING CHARACTERISTICS over COMMERCIAL operating ranges at 33 MHz
VCC = 5.0 V ± 10%; TCASE = 0°C to +100°C
Symbol
Parameter Description
Operating Frequency: Am386SX CPU
Am386SXL CPU
CLK2 Period
CLK2 High Time
CLK2 High Time
CLK2 Low Time
CLK2 Low Time
CLK2 Fall Time
CLK2 Rise Time
A23–A1 Valid Delay
A23–A1 Float Delay
BHE, BLE, LOCK Valid Delay
BHE, BLE, LOCK Float Delay
M/IO, D/C, W/R, ADS Valid Delay
W/R, M/IO, D/C, ADS Float Delay
D15–D0 Write Data Valid Delay
D15–D0 Write Data Hold Time
D15–D0 Write Data Float Delay
HLDA Valid Delay
HLDA Float Delay
NA Setup Time
NA Hold Time
READY Setup Time
READY Hold Time
D15–D0 Read Data Setup Time
D15–D0 Read Data Hold Time
HOLD Setup Time
HOLD Hold Time
RESET Setup Time
RESET Hold Time
NMI, INTR Setup Time
NMI, INTR Hold Time
PEREQ, ERROR, BUSY Setup Time
PEREQ, ERROR, BUSY Hold Time
Notes
Half CLK2 freq.
Half CLK2 freq.
Ref.
Figures
Final
Min Max
2
33
0
33
15
6.25
4
6.25
4.5
4
4
4
15
4
20
4
15
4
20
4
15
4
20
7
23
2
4
17
4
20
4
20
5
2
7
4
5
3
9
2
5
2
5
5
5
4
Unit
MHz
1
4
ns
2a
at 2 V
4
ns
2b
at 3.7 V
4
ns
3a
at 2 V
4
ns
3b
at 0.8 V
4
ns
4
3.7 V to 0.8 V
(Note 3)
4
ns
5
0.8 V to 3.7 V
(Note 3)
4
ns
8
ns
6
CL = 50 pF
7
(Note 1)
15
ns
CL = 50 pF
8
ns
8
(Note 1)
15
ns
9
10
CL = 50 pF
8
ns
(Note 1)
15
ns
11
8
ns
12
CL = 50 pF
12a
CL = 50 pF
10
ns
13
(Note 1)
15
ns
8
ns
14
CL = 50 pF
14f
15
ns
15
7
ns
7
ns
16
19
7
ns
7
ns
20
21
7
ns
22
7
ns
23
7
ns
24
7
ns
25
17
ns
26
17
ns
27
(Note 2)
7
ns
28
(Note 2)
7
ns
(Note 2)
7
ns
29
30
(Note 2)
7
ns
Notes:
1. Float condition occurs when maximum output current becomes less than ILO in magnitude. Float delay is not 100% tested.
2. These inputs are allowed to be asynchronous to CLK2. The setup and hold specifications are given for testing purposes, to
assure recognition within a specific CLK2 period.
3. Rise and Fall times are not tested. They are guaranteed by design characterization.
4. Min time is not 100% tested.
16
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
SWITCHING CHARACTERISTICS over COMMERCIAL operating ranges at 40 MHz
VCC = 5.0 V ± 5%; TCASE = 0°C to +100°C (Am386SX only)
Symbol
Parameter Description
Operating Frequency
CLK2 Period
CLK2 High Time
CLK2 Low Time
CLK2 Fall Time
CLK2 Rise Time
A23–A1 Valid Delay
A23–A1 Float Delay
BHE, BLE, LOCK Valid Delay
BHE, BLE, LOCK Float Delay
M/IO, D/C, W/R, ADS Valid Delay
W/R, M/IO, D/C, ADS Float Delay
D15–D0 Write Data Valid Delay
D15–D0 Write Data Hold Time
D15–D0 Write Data Float Delay
HLDA Valid Delay
HLDA Float Delay
NA Setup Time
NA Hold Time
READY Setup Time
READY Hold Time
D15–D0 Read Data Setup Time
D15–D0 Read Data Hold Time
HOLD Setup Time
HOLD Hold Time
RESET Setup Time
RESET Hold Time
NMI, INTR Setup Time
NMI, INTR Hold Time
PEREQ, ERROR, BUSY, FLT Setup Time
PEREQ, ERROR, BUSY, FLT Hold Time
Notes
Half CLK2 frequency
Ref.
Figures
Final
Min Max Unit
2
40 MHz
12.5 250
ns
4.5
ns
4.5
ns
4
ns
4
ns
4
13
ns
4
20
ns
4
13
ns
4
20
ns
4
13
ns
4
20
ns
7
18
ns
2
ns
4
17
ns
4
17
ns
4
17
ns
5
ns
2
ns
7
ns
4
ns
4
ns
3
ns
4
ns
2
ns
4
ns
2
ns
5
ns
5
ns
5
ns
4
ns
1
5
2
at 2.7 V
5
3
at 0.8 V
5
4
2.7 V to 0.8 V
(Note 3)
5
5
0.8 V to 2.7 V
(Note 3)
5
6
CL = 50 pF
8
7
(Note 1)
15
8
CL = 50 pF
8
9
(Note 1)
15
10
CL = 50 pF
8
11
(Note 1)
15
12
CL = 50 pF
(Note 4)
8
12a
CL = 50 pF
10
13
(Note 1)
15
14
CL = 50 pF
15
14f
15
15
7
16
7
19
7
20
7
21
7
22
7
23
7
24
7
25
17
26
17
27
(Note 2)
7
28
(Note 2)
7
29
(Note 2)
7
30
(Note 2)
7
Notes:
1. Float condition occurs when maximum output current becomes less than ILO in magnitude. Float delay is not 100% tested.
2. These inputs are allowed to be asynchronous to CLK2. The setup and hold specifications are given for testing purposes, to
assure recognition within a specific CLK2 period.
3. Rise and Fall times are not tested. They are guaranteed by design characterization.
4. Min time is not 100% tested.
Am386SX/SXL/SXLV Microprocessors Data Sheet
17
F I N A L
t1
t2
VIHC
CLK2
2.0 V
0.8 V
t3
t5
t4
Figure 3. CLK2 Timing (Am386SXLV 25 MHz)
16305C–004
t1
t2a
t2b
VCC – 0.8 V
CLK2
2.0 V
0.8 V
t3a
t5
t4
t3b
15022B-031
Figure 4. CLK2 Timing (Am386SX/SXL 25 and 33 MHz)
t1
t2
VCC – 0.8 V
CLK2
2.0 V
0.8 V
t3
t5
Figure 5. CLK2 Timing (Am386SX 40 MHz)
t4
15022B-031a
Am386SX/SXL/SXLV CPU Output
CL
15022B–032
Figure 6. AC Test Circuit
18
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
SWITCHING WAVEFORMS
Tx
φ 2
Tx
φ1
φ2
φ1
Tx
CLK2
t19, t19s*
t20, t20s*
t23
t24
t21
t22
t29
t30
READY,
SMIRDY*
HOLD
D15–D0
(Inputs)
BUSY, ERROR,
IIBEN*, PEREQ,
FLT
t15
t16
t27, t27s*
t28, t28s*
NA
SMI*, INTR, NMI
* – On Am386SXLV only
Figure 7. Input Setup and Hold Timing
Am386SX/SXL/SXLV Microprocessors Data Sheet
19
F I N A L
φ2
φ1
Tx
φ2
φ1
CLK2
t8
BHE+, BLE+
BE3–BE0*,
LOCK
Min
Max
Valid n
Valid n+1
t10, t10s*
Min
W/R, M/IO,
D/C, ADS,
SMIADS*
Max
Valid n
Valid n+1
t6
Min
A23–A1
Max
Valid n
Valid n+1
t12
D15–D0
(Outputs)
Valid n
t31
SMI*
Min
Valid n+1
Min
Valid n
HLDA+
+ – On Am386SX/SXL only
* – On Am386SXLV only
Figure 8. Output Valid Delay Timing
20
Max
Am386SX/SXL/SXLV Microprocessors Data Sheet
Max
Valid n+1
F I N A L
T1
φ1
φ2
CLK2
W/R
Min
t12
Max
Valid n
D15–D0
13605C–007
Figure 9. Write Data Valid Delay Timing
T1
φ1
φ2
CLK2
W/R
Min
t12a
D15–D0
Valid n
16305C–008
Figure 10. Write Data Hold Timing
Am386SX/SXL/SXLV Microprocessors Data Sheet
21
F I N A L
Internal Initialization
Reset
≥ 15 CLK2 duration if not
going to request self-test.
≥ 80 CLK2 duration before
requesting self-test.
Cycle 1
If self-test is performed, add
(220) + 60* to these numbers.
1
2
3
17
18
19
*
Non-Pipelined
(Read)
T1
T2
*
*
*
395 396 397 398
CLK2
* Approximately
Reset
φ2 φ1 φ2
φ1 φ 2 φ1 φ 2 φ1 φ 2
CLK (Internal)
No self-test
BUSY
Negated to allow sensing of a
387DX math coprocessor
(Note 1)
Low to begin self-test (Note 2)
Asserted to indicate 387DX
math coprocessor protocol
ERROR
BHE, BLE, W/R,
M/IO, HLDA
Up to 30 CLK2
Low
During Reset
Valid 1
High
During Reset
Valid 1
High
During Reset
Up to 30 CLK2
A23–A1,
D/C, LOCK
Up to 30 CLK2
ADS
NA
READY
D15–D0
(Floating)
SMI
Notes:
1. BUSY should be held stable for eight CLK2 periods before and after the CLK2 period in which the RESET falling edge
occurs.
2. If self-test is requested, the Am386SXLV microprocessor outputs remain in their reset state as shown here.
16305C–009
Figure 11. Bus Activity from Reset Until First Code Fetch (Am386SXLV Only)
22
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
φ1
φ1
φ1
φ1
φ1
φ1
φ1
φ1
φ1
φ1
CLK2
FLT
Control
Valid
Valid
Data
Valid
Address
Reset
SMI
Valid
16306B–008
Figure 12. Entering and Exiting FLT (Am386SXLV Only)
φ1
φ1
φ1
φ1
φ1
φ1
φ1
CLK2
SMM in progress
SMI
Drive released by CPU
System may initiate another
SMI when necessary*
SMIADS
CPU driving SMI
System control of SMI
*Once initiated, the system must hold SMI Low until the first SMIADS. At this time, the system cannot drive SMI until three
CLK2 cycles after the CPU drives SMI High. (The CPU will drive SMI High for two CLK2 cycles. The additional clock allows
the CPU to completely release SMI and prevents any driver overlap.)
16306B–011
Figure 13. Initiating and Exiting SMM (Am386SXLV Only)
φ2
φ2
CLK2
SMM in progress
SMI
RESET
CPU drives SMI High for two CLK2 cycles 6–8
clocks after RESET is asserted.
Figure 14. RESET and SMI (Am386SXLV Only)
Am386SX/SXL/SXLV Microprocessors Data Sheet
16306B–010
23
F I N A L
Cycle 0
Cycle 1
φ2
φ1
Th
Cycle 2
φ2
Ti or T1 φ 2
φ1
CLK2
t9
Min
Max
BHE, BLE,
LOCK
t8
Min
Max
Min
Max
Min
Max
(High Z)
t10, t10s*
t11, t11s*
Min
W/R, M/IO, D/C,
ADS, SMIADS*
Max
(High Z)
t7
Min
t6
Max
A23–A1
(High Z)
t13
Min
D15–D0
Max
t12
Min
Max
(High Z)
t13—Also applies to data float when write
cycle is followed by read or idle
t14f
Min
Max
t14
Min
Max
HLDA
Valid 0
SMI*
Valid 1
t31
Min
Max
* – On Am386SXLV only
Figure 15. Output Float Delay and HLDA and SMI* Valid Delay Timing
24
Am386SX/SXL/SXLV Microprocessors Data Sheet
Valid 2
F I N A L
φ2
φ1
Th
φ2
Ti or T1 φ 2
φ1
CLK2
t9
Min
BHE, BLE,
LOCK
t8
Max
Min
Max
Min
Max
Min
Max
(High Z)
t10, t10s
t11, t11s
Min
W/R, M/IO, D/C,
ADS, SMIADS
Max
(High Z)
t7
Min
A23–A1
t6
Max
(High Z)
t13
Min
Max
D15–D0
t12
Min
Max
(High Z)
t14f
Min
HLDA
Max
t14
Min
Max
(High Z)
t32
Min
SMI
t31
Max
Min
Max
(High Z)
16305C–012
Figure 16. Output Float Delay Entering and Exiting FLT (Am386SXLV Only)
RESET
Initialization Sequence
φ 2 or φ 1
φ 2 or φ 1
φ2
φ1
CLK2
t26
RESET
t25
The second internal processor phase following RESET High-to-Low transition (provided t25 and t26 are met) is φ2.
15021B–084
Figure 17. RESET Setup and Hold Timing and Internal Phase
Am386SX/SXL/SXLV Microprocessors Data Sheet
25
F I N A L
nom + 6
nom + 3
nom
Output Valid Delay (ns)
nom –3
nom –6
nom –9
50
75
100
125
CL (picofarads)
150
15021B–079
Note:
This graph will not be linear outside the CL range shown.
Figure 18. Typical Output Valid Delay Versus Load Capacitance
at Maximum Operating Temperature (CL =120 pF)
nom + 9
nom + 6
nom + 3
Output Valid Delay (ns)
nom
nom –3
nom –6
75
100
125
CL (picofarads)
150
Note:
This graph will not be linear outside the CL range shown.
Figure 19. Typical Output Valid Delay Versus Load Capacitance
at Maximum Operating Temperature (CL =75 pF)
26
Am386SX/SXL/SXLV Microprocessors Data Sheet
15021B–080
F I N A L
nom + 9
nom + 6
Output Valid Delay (ns)
nom + 3
nom
nom –3
50
75
100
125
CL (picofarads)
150
Note:
This graph will not be linear outside the CL range shown.
15021B–081
Figure 20. Typical Output Valid Delay Versus Load Capacitance
at Maximum Operating Temperature (CL =50 pF)
8
6
Rise Time (ns)
0.8 V – 2.0 V
4
2
8
50
75
100
125
CL (picofarads)
150
Note:
This graph will not be linear outside the CL range shown.
15021B–082
Figure 21. Typical Output Rise Time Versus Load Capacitance
at Maximum Operating Temperature
Am386SX/SXL/SXLV Microprocessors Data Sheet
27
F I N A L
DIFFERENCES BETWEEN THE Am386SX/SXL/SXLV AND Am386DX/DXL CPU
The following are the major differences between the
Am386SX/SXL/SXLV and the Am386DX/DXL CPU.
For brevity, throughout this section the Am386SX/SXL/
SXLV CPU is referred to as the SX CPU, and the
Am386DX/DXL CPU is referred to as the DX CPU.
■ The SX CPU generates byte selects on BHE and
BLE (like the 8086 and 80286) to distinguish the
upper and lower bytes on its 16-bit data bus. The
DX CPU uses four byte selects, BE3–BE0, to distinguish between the different bytes on its 32-bit bus.
■ The SX CPU has no bus sizing option. The DX CPU
can select between either a 32-bit bus or a 16-bit
bus by use of the BS16 input. The SX CPU has a
16-bit bus size.
■ The NA pin operation in the SX CPU is identical to
that of the NA pin on the DX CPU with one exception: the DX CPU NA pin cannot be activated on 16bit bus cycles (where BS16 is Low in the DX CPU
case), whereas NA can be activated on any SX
CPU bus cycle.
■ The contents of all SX CPU registers at reset are
identical to the contents of the DX CPU registers at
reset, except for the DX register. The DX register
contains a component-stepping identifier at reset,
that is:
– In the DX CPU, after reset:
DH = 3 indicates DX CPU
DI = revision number
– In the SX CPU, after reset:
DH = 23H indicates SX CPU
DL = revision number
28
■ The DX CPU uses A31 and M/IO as selects for the
math coprocessor. The SX CPU uses A23 and M/IO
as selects.
■ The DX CPU prefetch unit fetches code in four-byte
units. The SX CPU prefetch unit reads two bytes as
one unit (like the 80286). In BS16 mode, the DX
CPU takes two consecutive bus cycles to complete
a prefetch request. If there is a data read or write request after the prefetch starts, the DX CPU will fetch
all four bytes before addressing the new request.
■ Both the DX CPU and SX CPU have the same logical address space. The only difference is that the
DX CPU has a 32-bit physical address space and
the SX CPU has a 24-bit physical address space.
The SX CPU has a physical memory address space
of up to 16 Mbyte instead of the 4 Gbyte available
to the DX CPU. Therefore, in SX CPU systems, the
operating system must be aware of this physical
memory limit and should allocate memory for applications programs within this limit. If a DX CPU system uses only the lower 16 Mbyte of physical
address, then there will be no extra effort required
to migrate DX CPU software to the SX CPU. Any
application which uses more than 16 Mbyte of
memory can run on the SX CPU, if the operating
system utilizes the SX CPU’s paging mechanism. In
spite of this difference in physical address space,
the SX CPU and the DX CPU can run the same operating systems and applications within their respective physical memory constraints.
■ The SX CPU has an input called FLT, which threestates all bi-directional and output pins, including
HLDA, when asserted. It is used with ON-Circuit
Emulation (ONCE).
Am386SX/SXL/SXLV Microprocessors Data Sheet
F I N A L
PACKAGE THERMAL SPECIFICATIONS
The Am386SX/SXL/SXLV processors are specified for
operation when TCASE (the case temperature) is within
the range of 0°C to +100°C for commercial parts, and
–40°C to +100°C for industrial parts. TCASE can be measured in any environment to determine whether the
Am386SX/SXL/SXLV processors are within the specified operating range. The case temperature should be
measured at the center of the top surface opposite the
pins.
TJ = TCASE + P • θJC
TA = TJ – P • θJA
TCASE = TA + P • [θJA – θJC]
The ambient temperature (TA) is guaranteed as long as
TCASE is not violated. The ambient temperature can be
calculated from θJC and θJA and from these equations:
In the 100-lead PQFP package, θJA=45.0 and θJC=11.0.
where:
TJ, TA, TCASE = Junction, Ambient, and Case Temperature
= Junction-to-Case and Junction-to-Ambient
θJC, θJA
Thermal Resistance, respectively
P
= Maximum Power Consumption
ELECTRICAL SPECIFICATIONS
The Am386SX/SXL/SXLV CPU has modest power requirements. However, its high clock frequency and 47
output buffers (address, data, control, and HLDA) can
cause power surges as multiple output buffers drive
new signal levels simultaneously. For clean on-chip
power distribution at high frequency, 14 V CC and
18 V SS pins separately feed functional units of the
Am386SX/SXL/SXLV CPU.
Power and ground connections must be made to all external VCC and VSS pins of the Am386SX/SXL/SXLV
CPU. On the circuit board, all VCC pins should be connected on a VCC plane, and VSS pins should be connected on a GND plane.
Power Decoupling Recommendations
Liberal decoupling capacitors should be placed near
the Am386SX/SXL/SXLV CPU. The Am386SX/SXL/
SXLV CPU driving its 24-bit address bus and 16-bit
data bus at high frequencies can cause transient power
surges, particularly when driving large capacitive
loads. Low inductance capacitors and interconnects
are recommended for best high frequency electrical
performance. Inductance can be reduced by shortening circuit board traces between the Am386SX/SXL/
SXLV CPU and decoupling capacitors as much as possible.
Resistor Recommendations
The ERROR, FLT, and BUSY inputs have internal pullup resistors of approximately 20 Kohms, and the
Table 1.
PEREQ input has an internal pull-down resistor of approximately 20 Kohms, built into the Am386SX/SXL/
SXLV CPU to keep these signals inactive when a
387SX-compatible math coprocessor is not present in
the system (or temporarily removed from its socket).
In typical designs, the external pull-up resistors shown
in Table 1 are recommended. However, a particular design may have reason to adjust the resistor values recommended here, or alter the use of pull-up resistors in
other ways.
Other Connection Recommendations
For reliable operation, always connect unused inputs to
an appropriate signal level. NC pins should always remain unconnected. Connection of NC pins to VCC or
VSS will result in component malfunction or incompatibility with future steppings of the Am386SX/SXL/SXLV
CPU.
Particularly when not using the interrupts or bus hold
(as when first prototyping), prevent any chance of spurious activity by connecting these associated inputs to
GND:
Pin
40
38
4
Signal
INTR
NMI
HOLD
If not using address pipelining, connect pin 6 (NA)
through a pull-up in the range of 20 Kohms to VCC.
Recommended Resistor Pull-Ups to VCC
Pin
Signal
Pull-Up Value
Purpose
16
ADS
20 Kohms ± 10%
Lightly pull ADS inactive during Am386SX/SXL/SXLV
CPU Hold Acknowledge states.
26
LOCK
20 Kohms ± 10%
Lightly pull LOCK inactive during Am386SX/SXL/
SXLV CPU Hold Acknowledge states.
Am386SX/SXL/SXLV Microprocessors Data Sheet
29
F I N A L
PHYSICAL DIMENSIONS
PQB 100 (Plastic Quad Flat Pack, Trimmed and Formed)
0.875
0.885
Pin 100
0.897
0.903
0.747
0.753
Pin 75
Pin 1 I.D.
0.747
0.753
0.875
0.885
0.897
0.903
Pin 25
Pin 50
0.008
0.012
7° TYP.
0.010 MIN
FLAT SHOULDER
TOP VIEW
0.045 X45° CHAMFER
0° MIN
0.025 BASIC
0.130
0.150
0.015
R
0.008
0.160
0.180
SEATING
PLANE
0.60 REF
0.020
0.040
GAGE PLANE
0°≤0≤8°
0.010
0.036
0.046
7° TYP.
0.065 REF
BOTTOM VIEW
END VIEW
16-038-PQB
PQB100
DB90
3-6-97 lv
Trademarks
AMD, the AMD logo, and combinations thereof are trademarks of Advanced Micro Devices, Inc.
Am386 is a registered trademark; and E86 is a trademark of Advanced Micro Devices, Inc.
Product names used in this publication are for identification purposes only and may be trademarks of their respective companies.
30
Am386SX/SXL/SXLV Microprocessors Data Sheet