ETC PC755BVZFU300LD

Features
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
18.1SPECint95, estimates 12.3 SPECfp95 @400Mhz (PC755B)
15.7SPECint95, 9SPECfp95 @350Mhz (PC745B)
733 MIPS @ 400Mhz (PC755B) et 641 MIPS@350Mhz (PC745B)
Selectable bus clock (12 CPU bus dividers up to 10x)
PD typical 6,4W @ 400Mhz, full operating conditions.
Nap, doze and sleep modes for power savings
Superscalar (3 instructions per clock cycle) (two instruction + branch)
4 PetaByte virtual memory, 4 Gigabytes of physical memory.
64-bit data and 32-bit address bus interface.
32KB instruction and data cache.
Six independent execution units.
Write-back and write-through operations.
fint max = 400Mhz (TBC)
fbus max = 100Mhz
Voltage I/O 1,8V/3,3V ; voltage int 2.0 V
Description
PC755B and PC745B PowerPC microprocessors are high-performance, low-power, 32-bit
implementations of the PowerPC Reduced Instruction Set Computer (RISC) architecture, specially enhanced for embedded applications.
PC755B and PC745B microprocessors differ only in that the PC755B features an enhanced,
dedicated L2 cache interface with on-chip L2 tags. The PC755B is a drop-in replacement fo r the
award winning PowerPC 750TM microprocessor and is footprint and user software code compatible with the MPC7400 microprocessor withAltiVec TM technology. The PC745B is a drop-in
replacement for the PowerPC 740TM microprocessor and is also footprint and user soltware
code compatible with the PowerPC 603eTM microprocessor. PC755B/745B microprocessors
provide on-chip debug support and are fully JTAG-compliant.
PowerPC755B/745B
RISC MICROPROCESSOR
Preliminary
Specification α-site
PC755B/745B
The PC745B microprocessor is pin compatible with the TSPC603e family.
ZF suffix
ZF suffix
PBGA255
Flip-Chip Plastic Ball Grid Array
PBGA360
Flip-Chip Plastic Ball Grid Array
Screening
This product is manufactured in full compliance with :
H CBGA upscreenings based upon ATMEL-Grenoble standards
H Full military temperature range (Tj=-55oC,+125oC)
industrial temperature range (Tj=-40oC,+110oC)
September 2000
1/48
SUMMARY
4.2. Dynamic characteristics . . . . . . . . . . . . . . . . . . . . . 25
4.2.1. Clock AC Specifications . . . . . . . . . . . . . . . . . . . . . 25
1. SIMPLIFIED BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . 3
1.1. General parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2.2. Processor Bus AC Specifications . . . . . . . . . . . . . 26
4.2.3. L2 Clock AC Specifications . . . . . . . . . . . . . . . . . . 28
4.2.4. L2 Bus Input AC Specifications . . . . . . . . . . . . . . 31
4.2.5. IEEE 1149.1 AC Timing Specifications . . . . . . . . 33
2. PIN ASSIGNEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5. PREPARATION FOR DELIVERY . . . . . . . . . . . . . . . . . . 37
2.1. PINOUT LISTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1.1. Pinout listing for the PC745B, 255 PBGA . . . . . . . 9
2.1.2. Pinout listing for the PC755B, 360P PBGA
package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5.1. Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.2. Certificate of compliance . . . . . . . . . . . . . . . . . . . . 37
6. HANDLING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2.2. Signal description . . . . . . . . . . . . . . . . . . . . . . . . . . 15
7. PACKAGE MECHANICAL DATA . . . . . . . . . . . . . . . . . . 38
1. SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.1. Parameters for the PC745B . . . . . . . . . . . . . . . . . . 38
7.1.1. Package Parameters for the PC745B PBGA . . . 38
7.1.2. Mechanical Dimensions of the PC745B PBGA
2. APPLICABLE DOCUMENTS . . . . . . . . . . . . . . . . . . . . . 16
package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7.2. Parameters for the PC755B PBGA . . . . . . . . . . . . 40
3. REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2. Design and construction . . . . . . . . . . . . . . . . . . . . 16
7.2.1. Package parameter for the PC755B PBGA . . . . 40
7.2.2. Mechanical Dimensions of the PC755B PBGA . 40
8. CLOCK RELATIONSHIPS CHOICE . . . . . . . . . . . . . . . 41
3.2.1. Terminal connections . . . . . . . . . . . . . . . . . . . . . . 16
3.2.2. Absolute maximum rating . . . . . . . . . . . . . . . . . . . 16
9. SYSTEM DESIGN INFORMATION . . . . . . . . . . . . . . . . . 43
3.3. Recommendated operating conditions . . . . . . . 18
9.1. PLL Power Supply Filtering . . . . . . . . . . . . . . . . . . 43
3.4. Thermal characteristics . . . . . . . . . . . . . . . . . . . . . 18
9.2. Power Supply Voltage Sequencing . . . . . . . . . . . 43
3.4.1. Package characteristics . . . . . . . . . . . . . . . . . . . . . 18
9.3. Decoupling Recommendations . . . . . . . . . . . . . . 43
3.4.2. Thermal management assistance . . . . . . . . . . . . 19
9.4. Connection Recommendations . . . . . . . . . . . . . . 44
3.4.3. Thermal Management Information . . . . . . . . . . . . 20
9.5. Output Buffer DC Impedance . . . . . . . . . . . . . . . . 44
3.5. Power consideration . . . . . . . . . . . . . . . . . . . . . . . . 22
9.6. Pull-up Resistor Requirements . . . . . . . . . . . . . . 45
3.5.1. Power management . . . . . . . . . . . . . . . . . . . . . . . . 22
10. DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.5.2. Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4. ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . 24
4.1. Static characteristics . . . . . . . . . . . . . . . . . . . . . . . 24
2/48
PC755B/745B
11. DIFFERENCES WITH COMMERCIAL PART . . . . . . . 46
12. ORDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . 47
PC755B/745B
A. GENERAL DESCRIPTION
1. SIMPLIFIED BLOCK DIAGRAM
The PC755B is targeted for low power systems and supports the following power management features-doze, nap, sleep, and
dynamic power management. The PC755B consists of a processor core and an internal L2 Tag combined with a dedicated L2 cache
interface and a 60x bus.
Control Unit
Instruction Fetch
Branch Unit
Completion
32K ICache
System Unit
BHT/BTIC
Dispatch
GPRs
FXU1
FXU2
FPRs
LSU
Rename
Buffers
Rename
Buffers
FPU
L2 Cache
32K DCache
L2 Tags
BIU
60x BIU
Not In The PC745B
Figure 1 : PC755B Block Diagram
3/48
1.1. General parameters
The following list provides a summary of the general parameters of the PC755B:
Technology
0.22 m CMOS, six-layer metal
Die size
6.61 mm x 7.73 mm (51 mm2)
Transistor count
Logic design
6.75 million
Fully-staticPackages
PC745B:
Surface mount 255 plastic ball grid array (PBGA)
PC755B:
Surface mount 360 plastic ball grid array (PBGA)
Core power supply: 2.0V 100 mV dc (nominal; see table 5 for recommended operating conditions)
I/O power supply
1.8V 100 mV dc or
2.0V 100 mV dc or
3.3V 165mV dc (input thresholds are configuration pin selectable)
1.2. Features
This section summarizes features of the PC755B’s implementation of the PowerPC architecture. Major features of the PC755B are as
follows:
D Branch processing unit
- Four instructions fetched per clock
- One branch processed per cycle (plus resolving 2 speculations)
- Up to 1 speculative stream in execution, 1 additional speculative stream in fetch
- 512-entry branch history table (BHT) for dynamic prediction
- 64-entry, 4-way set associative Branch Target Instruction Cache (BTIC) for eliminating branch delay slots
D Dispatch unit
- Full hardware detection of dependencies (resolved in the execution units)
- Dispatch two instructions to six independent units (system, branch, load/store, fixed-point unit 1, fixed-point unit 2, floatingpoint)
- Serialization control (predispatch, postdispatch, execution serialization)
D Decode
- Register file access
- Forwarding control
- Partial instruction decode
D Completion
- 6 entry completion buffer
- Instruction tracking and peak completion of two instructions per cycle
- Completion of instructions in program order while supporting out-of- order instruction execution, completion serialization and
all instruction flow changes
D Fixed Point Units (FXUs) that share 32 GPRs for integer operands
- Fixed Point Unit 1 (FXU1)-multiply, divide, shift, rotate, arithmetic, logical
- Fixed Point Unit 2 (FXU2)-shift, rotate, arithmetic, logical
- Single-cycle arithmetic, shifts, rotates, logical
- Multiply and divide support (multi-cycle)
- Early out multiply
4/48
PC755B/745B
PC755B/745B
D Floating-point unit and a 32-entry FPR file
- Support for IEEE-754 standard single and double precision floating point arithmetic
- Hardware support for divide
- Hardware support for denormalized numbers
- Single-entry reservation station
- Supports non-IEEE mode for time-critical operations
D System unit
- Executes CR logical instructions and miscellaneous system instructions
- Special register transfer instructions
D Load/store unit
- One cycle load or store cache access (byte, half-word, word, double-word)
- Effective address generation
- Hits under misses (one outstanding miss)
- Single-cycle unaligned access within double word boundary
- Alignment, zero padding, sign extend for integer register file
- Floating point internal format conversion (alignment, normalization)
- Sequencing for load/store multiples and string operations
- Store gathering
- Cache and TLB instructions
- Big and Little-endian byte addressing supported
- Misaligned Little-endian supported
D Level 1 Cache structure
- 32K, 32-byte line, 8-way set associative instruction cache (iL1)
- 32K, 32-byte line, 8-way set associative data cache (dL1)
- Cache locking for both instruction and data caches, selectable by group of ways
- Single-cycle cache access
- Pseudo least-recently used (PLRU) replacement
- Copy-back or Write Through data cache (on a page per page basis)
- Supports all PowerPC memory coherency modes
- Non-Blocking instruction and data cache (one outstanding miss under hits)
- No snooping of instruction cache
D Level 2 (L2) Cache Interface (not implemented on PC745B)
- Internal L2 cache controller and tags; external data SRAMs
- 256K, 512K, and 1Mbyte 2-way set associative L2 cache support
- Copyback or write-through data cache (on a page basis, or for all L2)
- Instruction-only mode and data-only mode.
- 64byte (256K/512K) or 128byte (1M) sectored line size
- Supports flow through (register-buffer) synchronous burst SRAMs, pipelined (register-register) synchronous burst SRAMs
(3-1-1-1 or strobeless 4-1-1-1) and pipelined (register-register) late-write synchronous burst SRAMs
- L2 configurable to direct mapped SRAM interface or split cache/direct mapped or private memory
- Core-to-L2 frequency divisors of 1, 1.5, 2, 2.5, and 3 supported
- 64 bit data bus
- Selectable interface voltages of 1.8V/2.0V and 3.3V
- Parity checking on both L2 address and data
5/48
D Memory Management Unit
- 128 entry, 2-way set associative instruction TLB
- 128 entry, 2-way set associative data TLB
- Hardware reload for TLBs
- Hardware or optional software tablewalk support
- 8 instruction BATs and 8 data BATs
- 8 SPRGs, for assistance with software tablewalks
- Virtual memory support for up to 4 exabytes (252) of virtual memory
- Real memory support for up to 4 gigabytes (232) of physical memory
D Bus Interface
- Compatible with 60X processor interface
- 32-bit address bus
- 64-bit data bus, 32-bit mode selectable
- Bus-to-core frequency multipliers of 2x, 3x, 3.5x, 4x, 4.5x, 5x, 5.5x, 6x, 6.5x, 7x, 7.5x, 8x, 10x supported
- Selectable interface voltages of 3.3V and 1.8V/2.0V. Low voltage selection allows compatibility with either the 2.0V Vdd supply
or with 1.8V supplies needed for peripheral devices.
- Parity checking on both address and data busses
D Power management
- Low-power design with thermal requirements very similar to PC740/750.
- Selectable interface voltage of 1.8V/2.0V can reduce power in output buffers (compared to 3.3V)
- Three static power saving modes: doze, nap, and sleep
- Dynamic power management
D Testability
- LSSD scan design
- IEEE 1149.1 JTAG interface
D Integrated Thermal Management Assit Unit
- One -ship thermal sensor and control logic
- Thermal Management Interrrup for software regulation of junction temperature
6/48
PC755B/745B
PC755B/745B
2. PIN ASSIGNEMENTS
Figure 2 (in part A) shows the pinout of the PC745B, 255PBGA package as viewed from the top surface. Part B shows the side profile
of the PBGA package to indicate the direction of the top surface view.
Part A
Pinout of the PC745B, 255 PBGA Package as Viewed from the Top Surface
1 2
3
4
5 6 7 8
9 10 11 12 13 14 15 16
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
Not to Scale
Part B
Substrate Assembly
Encapsulant
View
Die
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
Figure 2 : Pinout of the PC745B, 255 PBGA Package as Viewed from the Top Surface
7/48
Figure 3 (in part A) shows the pinout of the PC755B, 360 PBGA packages as viewed from the top surface. Part B shows the side
profile of the PBGA package to indicate the direction of the top surface view.
Part A
1 2
3
4
9 10 11 12 13 14 15 16 17 18 19
5 6 7 8
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
U
V
W
Not to Scale
Part B
Substrate Assembly
Encapsulant
View
Die
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
Figure 3 : Pinout of the PC755B, 360 PBGA Packages as Viewed from the Top Surface
8/48
PC755B/745B
PC755B/745B
2.1. PINOUT LISTINGS
2.1.1. Pinout listing for the PC745B, 255 PBGA
Table 1 provides the pinout listing for the PC745B, 255 PBGA package.
Table 1. Pinout Listing for the PC745B, 255 PBGA Package
I/F Voltages
Supported1
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
A[0–31]
C16, E4, D13, F2, D14, G1, D15, E2,
D16, D4, E13, G2, E15, H1, E16, H2,
F13, J1, F14, J2, F15, H3, F16, F4,
G13, K1, G15, K2, H16, M1, J15, P1
High
I/O
—
—
AACK
L2
Low
Input
—
—
ABB
K4
Low
I/O
—
—
AP[0–3]
C1, B4, B3, B2
High
I/O
—
—
ARTRY
J4
Low
I/O
—
—
AVDD
A10
—
—
2.0V
2.0V
BG
L1
Low
Input
—
—
BR
B6
Low
Output
—
—
BVSEL
B1
High
Input
GND
3.3V
CI
E1
Low
Output
—
—
CKSTP_IN
D8
Low
Input
—
—
CKSTP_OUT
A6
Low
Output
—
—
CLK_OUT
D7
—
Output
—
—
DBB
J14
Low
I/O
—
—
DBG
N1
Low
Input
—
—
DBDIS
H15
Low
Input
—
—
DBWO
G4
Low
Input
—
—
DH[0–31]
P14, T16, R15, T15, R13, R12, P11,
N11, R11, T12, T11, R10, P9, N9, T10,
R9, T9, P8, N8, R8, T8, N7, R7, T7,
P6, N6, R6, T6, R5, N5, T5, T4
High
I/O
—
—
DL[0–31]
K13, K15, K16, L16, L15, L13, L14,
M16, M15, M13, N16, N15, N13, N14,
P16, P15, R16, R14, T14, N10, P13,
N12, T13, P3, N3, N4, R3, T1, T2, P4,
T3, R4
High
I/O
—
—
DP[0–7]
M2, L3, N2, L4, R1, P2, M4, R2
High
I/O
—
—
DRTRY
G16
Low
Input
—
—
GBL
F1
Low
I/O
—
—
Notes
3, 4, 5
9/48
Table 1. Pinout Listing for the PC745B, 255 PBGA Package
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
GND
GND
Notes
GND
C5, C12, E3, E6, E8, E9, E11, E14, F5, —
F7, F10, F12, G6, G8, G9, G11, H5,
H7, H10, H12, J5, J7, J10, J12, K6,
K8, K9, K11, L5, L7, L10, L12, M3, M6,
M8, M9, M11, M14, P5, P12
—
HRESET
A7
Low
Input
—
—
INT
B15
Low
Input
—
—
L1_TSTCLK
D11
High
Input
—
—
2
L2_TSTCLK
D12
High
Input
—
—
2
LSSD_MODE
B10
Low
Input
—
—
2
MCP
C13
Low
Input
—
—
NC (No–Connect)
B7, B8, C3, C6, C8, D5, D6, H4, J16,
A4, A5, A2, A3, B5
—
—
—
—
OVDD
C7, E5, E7, E10, E12, G3, G5, G12,
G14, K3, K5, K12, K14, M5, M7, M10,
M12, P7, P10
—
—
1.8V/2.0V
3.3V
PLL_CFG[0–3]
A8, B9, A9, D9
High
Input
—
—
QACK
D3
Low
Input
—
—
QREQ
J3
Low
Output
—
—
RSRV
D1
Low
Output
—
—
SMI
A16
Low
Input
—
—
SRESET
B14
Low
Input
—
—
SYSCLK
C9
—
Input
—
—
TA
H14
Low
Input
—
—
TBEN
C2
High
Input
—
—
TBST
A14
Low
I/O
—
—
TCK
C11
High
Input
—
—
TDI
A11
High
Input
—
—
TDO
A12
High
Output
—
—
TEA
H13
Low
Input
—
—
TLBISYNC
C4
Low
Input
—
—
TMS
B11
High
Input
—
—
5
TRST
C10
Low
Input
—
—
5
TS
J13
Low
I/O
—
—
TSIZ[0–2]
A13, D10, B12
High
Output
—
—
10/48
PC755B/745B
5
PC755B/745B
Table 1. Pinout Listing for the PC745B, 255 PBGA Package
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
TT[0–4]
B13, A15, B16, C14, C15
High
I/O
—
—
WT
D2
Low
Output
—
—
VDD 2
F6, F8, F9, F11, G7, G10, H6, H8, H9,
H11, J6, J8, J9, J11, K7, K10, L6, L8,
L9, L11
—
—
2.0V
2.0V
VOLTDET
F3
High
Output
—
—
Notes
6
Notes:
1. OVdd supplies power to the processor bus, JTAG, and all control signals and Vdd supplies power to the processor core
and the PLL (after filtering to become AVDD). These columns serve as a reference for the nominal voltage supported
on a given signal as selected by the BVSEL pin configuration of Table 4 and the voltage supplied. For actual recommended value of Vin or supply voltages see Table 3.
2. These are test signals for factory use only and must be pulled up to OVdd for normal machine operation.
3. To allow for future I/O voltage changes, provide the option to connect BVSEL independently to either OVDD (selects
3.3V) or to OGND (selects 1.8V/2.0V).
4. Uses one of 15 existing no-connects in PC745’s 255-bga package.
5. Internal pull up on die.
6. Internally tied to GND in the PC745B 255-bga package to indicate to the power supply that a low-voltage processor
is present. This signal is not a power supply input.
2.1.2. Pinout listing for the PC755B, 360P PBGA package.
Table 2 provides the pinout listing for the PC755B, 360 PBGA.
Table 2. Pinout Listing for the PC755B, 360 PBGA Package
I/F Voltages
Supported1
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
A[0–31]
A13, D2, H11, C1, B13, F2, C13, E5,
D13, G7, F12, G3, G6, H2, E2, L3, G5,
L4, G4, J4, H7, E1, G2, F3, J7, M3,
H3, J2, J6, K3, K2, L2
High
I/O
—
—
AACK
N3
Low
Input
—
—
ABB
L7
Low
I/O
—
—
AP[0–3]
C4, C5, C6, C7
High
I/O
—
—
ARTRY
L6
Low
I/O
—
—
AVDD
A8
—
—
2.0V
2.0V
BG
H1
Low
Input
—
—
BR
E7
Low
Output
—
—
BVSEL
W1
High
Input
GND
3.3V
CI
C2
Low
Output
—
—
CKSTP_IN
B8
Low
Input
—
—
Notes
3, 5, 6
11/48
Table 2. Pinout Listing for the PC755B, 360 PBGA Package
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
CKSTP_OUT
D7
Low
Output
—
—
CLK_OUT
E3
—
Output
—
—
DBB
K5
Low
I/O
—
—
DBDIS
G1
Low
Input
—
—
DBG
K1
Low
Input
—
—
DBWO
D1
Low
Input
—
—
DH[0–31]
W12, W11, V11, T9, W10, U9, U10,
M11, M9, P8, W7, P9, W9, R10, W6,
V7, V6, U8, V9, T7, U7, R7, U6, W5,
U5, W4, P7, V5, V4, W3, U4, R5
High
I/O
—
—
DL[0-31]
M6, P3, N4, N5, R3, M7, T2, N6, U2,
N7, P11, V13, U12, P12, T13, W13,
U13, V10, W8, T11, U11, V12, V8, T1,
P1, V1, U1, N1, R2, V3, U3, W2
High
I/O
—
—
DP[0–7]
L1, P2, M2, V2, M1, N2, T3, R1
High
I/O
—
—
DRTRY
H6
Low
Input
—
—
GBL
B1
Low
I/O
—
—
GND
D10, D14, D16, D4, D6, E12, E8, F4,
F6, F10, F14, F16, G9, G11, H5, H8,
H10, H12, H15, J9, J11, K4, K6, K8,
K10, K12, K14, K16, L9, L11, M5, M8,
M10, M12, M15, N9, N11, P4, P6, P10,
P14, P16, R8, R12, T4, T6, T10, T14,
T16
—
—
GND
GND
HRESET
B6
Low
Input
—
—
INT
C11
Low
Input
—
—
L1_TSTCLK
F8
High
Input
—
—
L2ADDR[0–16]
L17, L18, L19, M19, K18, K17, K15,
J19, J18, J17, J16, H18, H17, J14,
J13, H19, G18
High
Output
—
—
L2AVDD
L13
—
—
2.0V
2.0V
L2CE
P17
Low
Output
—
—
L2CLKOUTA
N15
—
Output
—
—
L2CLKOUTB
L16
—
Output
—
—
12/48
PC755B/745B
Notes
2
PC755B/745B
Table 2. Pinout Listing for the PC755B, 360 PBGA Package
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
Notes
L2DATA[0–63]
U14, R13, W14, W15, V15, U15, W16,
V16, W17, V17, U17, W18, V18, U18,
V19, U19, T18, T17, R19, R18, R17,
R15, P19, P18, P13, N14, N13, N19,
N17, M17, M13, M18, H13, G19, G16,
G15, G14, G13, F19, F18, F13, E19,
E18, E17, E15, D19, D18, D17, C18,
C17, B19, B18, B17, A18, A17, A16,
B16, C16, A14, A15, C15, B14, C14,
E13
High
I/O
—
—
L2DP[0–7]
V14, U16, T19, N18, H14, F17, C19,
B15
High
I/O
—
—
L2OVDD
D15, E14, E16, H16, J15, L15, M16,
P15, R14, R16, T15, F15
—
—
1.8V/2.0V
3.3V
L2SYNC_IN
L14
—
Input
—
—
L2SYNC_OUT
M14
—
Output
—
—
L2_TSTCLK
F7
High
Input
—
—
2
L2VSEL
A19
High
Input
GND
3.3V
1, 3, 5, 6
L2WE
N16
Low
Output
—
—
L2ZZ
G17
High
Output
—
—
LSSD_MODE
F9
Low
Input
—
—
MCP
B11
Low
Input
—
—
NC (No-Connect)
B3, B4, B5, W19, K9, K114, K194
—
—
—
—
OVDD
D5, D8, D12, E4, E6, E9, E11, F5, H4,
J5, L5, M4, P5, R4, R6, R9, R11, T5,
T8, T12
—
—
1.8V/2.0V
3.3V
PLL_CFG[0–3]
A4, A5, A6, A7
High
Input
—
—
QACK
B2
Low
Input
—
—
QREQ
J3
Low
Output
—
—
RSRV
D3
Low
Output
—
—
SMI
A12
Low
Input
—
—
SRESET
E10
Low
Input
—
—
SYSCLK
H9
—
Input
—
—
TA
F1
Low
Input
—
—
TBEN
A2
High
Input
—
—
TBST
A11
Low
I/O
—
—
TCK
B10
High
Input
—
—
2
13/48
Table 2. Pinout Listing for the PC755B, 360 PBGA Package
Signal Name
Pin Number
Active
I/O
1.8V/2.0V
3.3V
Notes
6
TDI
B7
High
Input
—
—
TDO
D9
High
Output
—
—
TEA
J1
Low
Input
—
—
TLBISYNC
A3
Low
Input
—
—
TMS
C8
High
Input
—
—
6
TRST
A10
Low
Input
—
—
6
TS
K7
Low
I/O
—
—
TSIZ[0–2]
A9, B9, C9
High
Output
—
—
TT[0–4]
C10, D11, B12, C12, F11
High
I/O
—
—
WT
C3
Low
Output
—
—
VDD
G8, G10, G12, J8, J10, J12, L8, L10,
L12, N8, N10, N12
—
—
2.0V
2.0V
VOLTDET
K13
High
Output
—
—
7
Notes:
1. OVdd supplies power to the processor bus, JTAG, and all control signals except the L2 cache controls (L2CE, L2WE,
and L2ZZ); L2OVDD supplies power to the L2 cache interface (L2ADDR[0-16], L2DATA[0-63], L2DP[0-7] and
L2SYNC-OUT) and the L2 control signals; and Vdd supplies power to the processor core and the PLL and DLL (after
filtering to become AVDD and L2AVDD respectively). These columns serve as a reference for the nominal voltage supported on a given signal as selected by the BVSEL/L2VSEL pin configurations of Table 4 and the voltage supplied. For
actual recommended value of Vin or supply voltages see Table 5.
2. These are test signals for factory use only and must be pulled up to OVdd for normal machine operation.
3. To allow for future I/O voltage changes, provide the option to connect BVSEL and L2VSEL independently to either
OVDD (selects 3.3V) or to OGND (selects 1.8V/2.0V).
4. These pins are reserved for potential future use as additional L2 address pins.
5. Uses one of 9 existing no-connects in PC750’s 360-bga package.
6. Internal pull up on die.
7. Internally tied to L2OVDD in the PC755B 360-bga package to indicate the power present at the L2 cache interface. This
signal is not a power supply input.
Caution: This is different from the PC745B 255-bga package.
14/48
PC755B/745B
PC755B/745B
2.2. Signal description
L2VDD
L2AVDD
Not supported in the PC745B
L2VSEL
BR
BG
ADDRESS
ARBITRATION
ABB
ADDRESS
START
TS
A[0-31]
ADDRESS
BUS
AP[0-3]
1
17
1
1
64
8
1
1
32
1
2
L2DATAƪ0-63ƫ
L2DPƪ0-7ƫ
L2WE
L2CLK-OUTƪA-Bƫ
L2SYNC_OUT
TS1Z[0-2]
GBL
TRANSFER
ATTRIBUTE
WT
CI
BVSEL
5
1
1
1
3
1
1
1
1
1
1
1
1
PC755B
1
L2ZZ
INT
SMI
AACK
DATA
ARBITRATION
DATA
TRANSFER
SRESET
HRESET
CKSTP_IN
CKSTP_OUT
RSRV
TBEN
TLBISYNC
QREQ
ARTRY
1
1
1
1
DBG
1
1 SYSCLK,
PLL_CFGƪ0-3ƫ
4
CLK_OUT
1
DBWO
DBB
1
1
Dƪ0-63ƫ
DPƪ0-7ƫ
DBDIS
DATA
TERMINATION
INTERRUPTS
RESET
MCP
1
1
1
ADDRESS
TERMINATION
TA
DRTRY
TEA
64
8
1
L2 CACHE
CLOCK/CONTROL
L2SYNC_IN
1
TT[0-4]
TBST
L2 CACHE
ADDRESS/
DATA
L2CE
1
4
L2ADDRƪ16-0ƫ
PROCESSOR
STATUS
CONTROL
QACK
5
3
JTAG:COP
Factory Test
1
VOLTDET
CLOCK
CONTROL
TEST INTERFACE
1
1
1
VDD OVDD
AVDD
GND
Figure 4 : PC755B microprocessor signal groups
15/48
B. DETAILED SPECIFICATION
1. SCOPE
This drawing describes the specific requirements for the microprocessor PC755B, in compliance with ATMEL Grenoble standard
screening.
2. APPLICABLE DOCUMENTS
1) MIL-STD-883 : Test methods and procedures for electronics.
2) MIL-PRF-38535 appendix A : General specifications for microcircuits.
3. REQUIREMENTS
3.1. General
The microcircuits are in accordance with the applicable documents and as specified herein.
3.2. Design and construction
3.2.1. Terminal connections
Depending on the package, the terminal connections is shown in table 1, table 2 and Figure 4.
3.2.2. Absolute maximum rating
Table 3. Absolute Maximum Ratings
Characteristic
Symbol
Maximum Value
Unit
Note
Core supply voltage
Vdd
–0.3 to 2.5
V
4
PLL supply voltage
AVdd
–0.3 to 2.5
V
4
L2 DLL supply voltage
L2AVdd
–0.3 to 2.5
V
4
Processor bus supply voltage
OVdd
–0.3 to 3.465
V
3
L2 bus supply voltage
L2OVdd
–0.3 to 3.465
V
3
Input voltage
Storage temperature range
Processor bus
Vin
–0.3 to OVdd + 0.3V
V
2,5
L2 Bus
Vin
–0.3 to L2OVdd + 0.3V
V
2,5
JTAG Signals
Vin
–0.3 to 3.6
V
Tstg
–55 to 150
oC
Notes:
1. Functional and tested operating conditions are given in Table 4. Absolute maximum ratings are stress ratings only,
and functional operation at the maximums is not guaranteed. Stresses beyond those listed may affect device reliability or cause permanent damage to the device.
2. Caution: Vin must not exceed OVdd or L2OVdd by more than 0.3V at any time including during power-on reset.
3. Caution: L2OVdd/OVdd must not exceed Vdd/AVdd/L2AVdd by more than 1.2V at any time including during power-on reset.
4. Caution: Vdd/AVdd/L2AVdd must not exceed L2OVdd/OVdd by more than 0.4V at any time including during power-on reset.
5. Vin may overshoot/undershoot to a voltage and for a maximum duration as shown in Figure 2.
16/48
PC755B/745B
PC755B/745B
Figure 5 shows the allowable undershoot and overshoot voltage on the PC755B and PC745B
(L2) OVdd +20%
(L2) OVdd +5%
(L2) OVdd
VIH
VIL
Gnd
Gnd - 0.3V
Gnd - 1.0V
Not to exceed 10%
of tSYSCLK
Figure 5 : Overshoot/Undershoot Voltage
The PC755B provides several I/O voltages to support both compatibility with existing systems and migration to future systems. The
PC755B core voltage must always be provided at nominal 2.0V (see Table 5 for actual recommended core voltage). Voltage to the L2
I/Os and Processor Interface I/Os are provided through separate sets of supply pins and may be provided at the voltages shown in
Table 4. The input voltage threshold for each bus is selected by sampling the state of the voltage select pins BVSEL and L2VSEL
during operation. These signals must remain stable during part operation and cannot change. The output voltage will swing from GND
to the maximum voltage applied to the OVdd or L2OVdd power pins.
Table 4 describes the input threshold voltage setting .
Table 4. Input Threshold Voltage Setting
BVSEL Signal
L2VSEL Signal
Processor Bus Interface
Voltage
L2 Bus
Interface Voltage
0
0
1.8V or 2.0V
1.8V or 2.0V
0
1
1.8V or 2.0V
3.3V
1
0
3.3V
1.8V or 2.0V
1
1
3.3V
3.3V
Note
Caution: The input threshold selection must agree with the OVdd/L2OVdd voltages supplied.
17/48
3.3. Recommendated operating conditions
Table 5. Recommended Operating Conditions
Characteristic
Symbol
Recommended
Value
Unit
Core supply voltage
Vdd
2.0v 100mV
V
PLL supply voltage
AVdd
2.0v 100mV
V
L2 DLL supply voltage
L2AVdd
2.0v 100mV
V
OVdd
1.8v 100mV or
V
Processor bus supply
voltage
L2 bus supply voltage
BVSEL = 0
2.0 100mV
BVSEL = 1
OVdd
3.3v 165mV
V
L2VSEL = 0
L2OVdd
1.8v 100mV or
V
2.0 100mV
Input voltage
L2VSEL = 1
L2OVdd
3.3v 165mV
V
Processor bus
Vin
GND to OVdd
V
L2 Bus
Vin
GND to L2OVdd
V
JTAG Signals
Vin
GND to OVdd
V
Tj
-55 to 125
Die-junction temperature
oC
Note : These are the recommended and tested operating conditions. Proper device operation outside of these
conditions is not guaranteed.
3.4. Thermal characteristics
3.4.1. Package characteristics
Table 6 provides the package thermal characteristics for the PC755B.
Table 6. Package Thermal Characteristics
Characteristic
Symbol
Value
Rating
PBGA package thermal resistance, junction-to-case thermal resistance (typical)
θJC
0.03
C/W
PBGA package thermal resistance, die junction-to-lead thermal resistance (typical)
θJB
12
C/W
PBGA package typical thermal resistance, die junction-to-ambient resistance
(convection only on 2S2P board)
θJA
33
C/W
PBGA package thermal resistance, die junction-to-ambient resistance (100 ft/min
airflow on 2S2P board)
θJA
30
C/W
Note:
Refer to Section 3.4.3. , “Thermal Management Information,” for more details about thermal management.
The board designer can choose between several types of heat sinks to place on the PC755B. There are several commercially-available heat sinks for the PC755B provided by the following vendors:
For the exposed-die packaging technology, shown in Table 5, the intrinsic conduction thermal resistance paths are as follows :
D The die junction-to-case (or top-of-die for exposed silicon) thermal resistance
D The die junction-to-ball thermal resistance
Figure 6 depicts the primary heat transfer path for a package with an attached heat sink mounted to a printed-circuit board.
Heat generated on the active side of the chip is conducted through the silicon, then through the heat sink attach material (or thermal
interface material), and finally to the heat sink where it is removed by forced-air convection.
18/48
PC755B/745B
PC755B/745B
Since the silicon thermal resistance is quite small, for a first-order analysis, the temperature drop in the silicon may be neglected.
Thus, the heat sink attach material and the heat sink conduction/convective thermal resistances are the dominant terms.
External Resistance
Radiation
Convection
Heat Sink
Thermal Interface Material
Die/Package
Die Junction
Package/Leads
Internal Resistance
Printed–Circuit Board
Radiation
External Resistance
Convection
(Note the internal versus external package resistance)
Figure 6 : C4 Package with Heat Sink Mounted to a Printed-Circuit Board
3.4.2. Thermal management assistance
The PC755B incorporates a thermal management assist unit (TAU) composed of a thermal sensor, digital-to-analog converter,
comparator, control logic, and dedicated special-purpose registers (SPRs). Specifications for the thermal sensor portion of the TAU
are found in Table 7. More information on the use of this feature is given in the Motorola PC755B RISC Microprocessor User’s manual.
Table 7. Thermal Sensor Specifications
At recommended operating conditions (See Table 5)
Characteristic
Min
Max
Unit
oC
Notes
Temperature range
0
127
Comparator settling time
20
—
s
Resolution
4
—
oC
3
+12
oC
3
Accuracy
-12
1
2,3
Notes:
1. The temperature is the junction temperature of the die. The thermal assist unit’s raw output does not indicate an
absolute temperature, but must be interpreted by software to derive the absolute junction temperature. For information about the use and calibration of the TAU, see Motorola Application Note AN1800/D, “Programming the
Thermal Assist Unit in the PC750 Microprocessor”.
2. The comparator settling time value must be converted into the number of CPU clocks that need to be written into
the THRM3 SPR.
3. Guaranteed by design and characterization.
19/48
3.4.3. Thermal Management Information
This section provides thermal management information for the ceramic ball grid array (BGA) package for air-cooled applications.
Proper thermal control design is primarily dependent upon the system-level design-the heat sink, airflow and thermal interface material. To reduce the die-junction temperature, heat sinks may be attached to the package by several methods–adhesive, spring clip to
holes in the printed-circuit board or package, and mounting clip and screw assembly; see Figure 7. This spring force should not
exceed 5.5 pounds of force.
BGA Package
Heat Sink
Heat Sink
Clip
Adhesive
or
Thermal Interface Material
Printed–Circuit Board
Option
Figure 7 : Package Exploded Cross-Sectional View with Several Heat Sink Options
Ultimately, the final selection of an appropriate heat sink depends on many factors, such as thermal performance at a given air velocity, spatial volume, mass, attachment method, assembly, and cost.
3.4.3.1. Adhesives and Thermal Interface Materials
Silicone Sheet (0.006 inch)
Bare Joint
Floroether Oil Sheet (0.007 inch)
Graphite/Oil Sheet (0.005 inch)
Synthetic Grease
Specific Thermal Resistance (Kin2/W)
2
1.5
1
0.5
0
0
10
20
30
40
50
Contact Pressure (psi)
60
70
Figure 8 : Thermal Performance of Select Thermal Interface Material
20/48
PC755B/745B
80
PC755B/745B
A thermal interface material is recommended at the package lid-to-heat sink interface to minimize the thermal contact resistance. For
those applications where the heat sink is attached by spring clip mechanism, Figure 8 shows the thermal performance of three thinsheet thermal-interface materials (silicone, graphite/oil, floroether oil), a bare joint, and a joint with thermal grease as a function of
contact pressure. As shown, the performance of these thermal interface materials improves with increasing contact pressure. The
use of thermal grease significantly reduces the interface thermal resistance. That is, the bare joint results in a thermal resistance
approximately 7 times greater than the thermal grease joint.
Heat sinks are attached to the package by means of a spring clip to holes in the printed-circuit board (see Figure 7 ). This spring force
should not exceed 5.5 pounds of force. Therefore, the synthetic grease offers the best thermal performance, considering the low
interface pressure.
The board designer can choose between several types of thermal interface. Heat sink adhesive materials should be selected based
upon high conductivity, yet adequate mechanical strength to meet equipment shock/vibration requirements.
3.4.3.2. Heat Sink Selection Example
For preliminary heat sink sizing, the die-junction temperature can be expressed as follows:
Tj = Ta + Tr + (θjc + θint + θsa) * Pd
Where:
Tj is the die-junction temperature
Ta is the inlet cabinet ambient temperature
Tr is the air temperature rise within the computer cabinet
θjc is the junction-to-case thermal resistance
θint is the adhesive or interface material thermal resistance
θsa is the heat sink base-to-ambient thermal resistance
Pd is the power dissipated by the device
During operation the die-junction temperatures (Tj) should be maintained less than the value specified in Table 5. The temperature of
the air cooling the component greatly depends upon the ambient inlet air temperature and the air temperature rise within the electronic
cabinet. An electronic cabinet inlet-air temperature (Ta) may range from 30 to 40 oC. The air temperature rise within a cabinet (Tr) may
be in the range of 5 to 10 oC. The thermal resistance of the thermal interface material (θint) is typically about 1 C/W. Assuming a Ta of 30
oC, a T of 5 oC, a CBGA package θ = 0.03, and a power consumption (P ) of 5.0 watts, the following expression for T is obtained:
r
jc
d
j
Die-junction temperature: Tj = 30 oC + 5 oC + (0.03 oC/W + 1.0 oC/W + θsa) * 5.0 W
For a Thermalloy heat sink #2328B, the heat sink-to-ambient thermal resistance (θsa) versus airflow velocity is shown in Figure 9.
8
Thermalloy #2328B Pin–fin Heat Sink
(25 x28 x 15 mm)
Heat Sink Thermal Resistance oC/W)
7
6
5
4
3
2
1
0
0.5
1
1.5
2
2.5
Approach Air Velocity (m/s)
3
3.5
Figure 9 : Thermalloy #2328B Heat Sink-to-Ambient Thermal Resistance Versus Airflow Velocity
21/48
Assuming an air velocity of 0.5 m/s, we have an effective Rsa of 7 oC/W, thus
Tj = 30 oC+ 5 oC+ (0.03 oC/W +1.0 oC/W + 7 oC/W) * 5.0 W,
resulting in a die-junction temperature of approximately 81 oC which is well within the maximum operating temperature of the component.
Other heat sinks offered by Chip Coolers, IERC, Thermalloy, Wakefield Engineering, and Aavid Engineering offer different heat sinkto-ambient thermal resistances, and may or may not need air flow.
Though the die junction-to-ambient and the heat sink-to-ambient thermal resistances are a common figure-of-merit used for comparing the thermal performance of various microelectronic packaging technologies, one should exercise caution when only using this
metric in determining thermal management because no single parameter can adequately describe three-dimensional heat flow. The
final die-junction operating temperature, is not only a function of the component-level thermal resistance, but the system-level design
and its operating conditions. In addition to the component’s power consumption, a number of factors affect the final operating die-junction temperature—airflow, board population (local heat flux of adjacent components), heat sink efficiency, heat sink attach, heat sink
placement, next-level interconnect technology, system air temperature rise, altitude, etc.
Due to the complexity and the many variations of system-level boundary conditions for today’s microelectronic equipment, the combined effects of the heat transfer mechanisms (radiation, convection and conduction) may vary widely. For these reasons, we recommend using conjugate heat transfer models for the board, as well as, system-level designs. To expedite system-level thermal analysis, several “compact” thermal-package models are available within FLOTHERM. These are available upon request.
3.5. Power consideration
3.5.1. Power management
The PC755B provides four power modes, selectable by setting the appropriate control bits in the MSR and HIDO registers. The four
power modes are as follows :
D Full-power: This is the default power state of the PC755B. The PC755B is fully powered and the internal functional units are operating at the full processor clock speed. If the dynamic power management mode is enabled, functional units that are idle will automatically enter a low-power state without affecting performance, software execution, or external hardware.
D Doze: All the functional units of the PC755B are disabled except for the time base/decrementer registers and the bus snooping
logic. When the processor is in doze mode, an external asynchronous interrupt, a system management interrupt, a decrementer
exception, a hard or soft reset, or machine check brings the PC755B into the full-power state. The PC755B in doze mode maintains
the PLL in a fully powered state and locked to the system external clock input (SYSCLK) so a transition to the full-power state takes
only a few processor clock cycles.
D Nap: The nap mode further reduces power consumption by disabling bus snooping, leaving only the time base register and the
PLL in a powerred state. The PC755B returns to the full-power state upon receipt of an external asynchronous interrupt, a system
management interrupt, a decrementer exception, a hard or soft reset, or a machine check input (MCP). A return to full-power state
from a nap state takes only a few processor clock cycles. When the processor is in nap mode, if QACK is negated, the processor
is put in doze mode to support snooping.
D Sleep: Sleep mode minimizes power consumption by disabling all internal functional units, after which external system logic may
disable the PPL and SUSCLK. Returning the PC755B to the full-power state requires the enabling of the PPL and SYSCLK, followed by the assertion of an external asynchronous interrupt, a system management interrupt, a hard or soft reset, or a machine
check input (MCP) signal after the time required to relock the PPL.
22/48
PC755B/745B
PC755B/745B
3.5.2. Power dissipation
Table 8. Power Consumption for PC755B
Processor (CPU) Frequency
300MHz
350MHz
Unit
Notes
400MHz
Full-On Mode
Typical
3.3
3.9
4.4
W
1, 3
Maximum
4.9
5.7
6.4
W
1, 2
2.3
W
1, 2
530
mW
1, 2
470
mW
1, 2
Doze Mode
Maximum
1.8
2.0
Nap Mode
Maximum
500
510
Sleep Mode
Maximum
460
470
Sleep Mode–PLL and DLL Disabled
Typical
340
340
340
mW
1, 3
Maximum
430
430
430
mW
1, 2
Notes:
1. These values apply for all valid processor bus and L2 bus ratios. The values do not include I/O Supply
Power (OVdd and L2OVdd) or PLL/DLL supply power (AVdd and L2AVdd). OVdd and L2OVdd power
is system dependent, but is typically <10% of Vdd power. Worst case power consumption for AVdd
= 15 mw and L2AVdd = 15 mW.
2. Maximum power is measured at Vdd = 2.1V while running an entirely cache-resident, contrived
sequence of instructions which keep the execution units maximally busy.
3. Typical power is an average value measured at Vdd = AVdd = L2AVdd = 2.0V, OVdd = L2OVdd =
3.3V in a system executing typical applications and benchmark sequences.
23/48
4. ELECTRICAL CHARACTERISTICS
4.1. Static characteristics
Table 9. DC Electrical Specifications
At recommended operating conditions (See Table 5)
Characteristic
NominalB
us
Voltage1
Symbol
1.8/2.0
Min
Max
VIH
0.65 * (L2)OVdd
(L2)OVdd + 0.15
V
2,3
3.3
VIH
2.0
(L2)OVdd + 0.3
V
2,3
1.8/2.0
VIL
-0.3
0.35 * (L2)OVdd
V
2
3.3
VIL
-0.3
0.8
V
1.8/2.0
KVIH
1.5
OVdd + 0.3
V
3.3
KVIH
2.4
OVdd + 0.3
V
1.8/2.0
KVIL
-0.3
0.2
V
3.3
KVIL
-0.3
0.4
V
Input leakage current, Vin =
L2OVdd/OVdd
Iin
—
10
µA
2,3
Hi-Z (off-state) leakage current, Vin =
L2OVdd/OVdd
ITSI
—
10
µA
2,3,5
1.8/2.0
VOH
(L2)OVdd - 0.45
—
V
3.3
VOH
2.4
—
V
1.8/2.0
VOL
—
0.45
V
3.3
VOL
—
0.4
V
Cin
—
5.0
pF
Input high voltage (all inputs except
SYSCLK)
Input low voltage (all inputs except
SYSCLK)
SYSCLK input high voltage
SYSCLK input low voltage
Output high voltage, IOH = -6 mA
Output low voltage, IOL = 6 mA
Capacitance, Vin = 0 V, f = 1 MHz
Unit
Notes
3,4
Notes:
1. Nominal voltages; See Table 5 for recommended operating conditions.
2. For processor bus signals, the reference is OVdd while L2OVdd is the reference for the L2 bus signals.
3. Excludes test signals (LSSD_MODE, L1_TSTCLK, L2_TSTCLK) and IEEE 1149.1 boundary scan (JTAG) signals.
4. Capacitance is periodically sampled rather than 100% tested.
5. The leakage is measured for nominal OVdd and Vdd, or both OVdd and Vdd must vary in the same direction (for example, both
OVdd and Vdd vary by either +5% or -5%).
24/48
PC755B/745B
PC755B/745B
4.2. Dynamic characteristics
After fabrication, parts are sorted by maximum processor core frequency as shown in Section 4.2.1.,“Clock AC Specifications” and
tested for conformance to the AC specifications for that frequency. These specifications are for 275, 300, 333 MHz processor core
frequencies. The processor core frequency is determined by the bus (SYSCLK) frequency and the settings of the PLL_CFG[0–3]
signals. Parts are sold by maximum processor core frequency.
4.2.1. Clock AC Specifications
Table 10 provides the clock AC timing specifications as defined in Table 3.
Table 10. Clock AC Timing Specifications
At recommended operating conditions (See Table 5)
Characteristic
Symbol
Maximum Processor Core Frequency
300 MHz
Min
Max
350 MHz
Min
Max
Unit
Notes
400 MHz
Min
Max
Processor frequency
fcore
200
300
200
350
200
400
MHz
1
VCO frequency
fVCO
400
600
400
700
400
800
MHz
1
SYSCLK frequency
fSYSCLK
25
100
25
100
25
100
MHz
1
SYSCLK cycle time
tSYSCLK
10
40
10
40
10
40
ns
SYSCLK rise and fall time
tKR & tKF
—
2.0
—
2.0
—
2.0
ns
2
tKR & tKF
—
1.0
—
1.0
—
1.0
ns
2
SYSCLK duty cycle
measured at OVdd/2
tKHKL/tSYSC
40
60
40
60
40
60
%
3
SYSCLK jitter
—
150
—
150
—
150
ps
3,4
Internal PLL relock time
—
100
—
100
—
100
µs
3,5
LK
Notes:
1. Caution: The SYSCLK frequency and PLL_CFG[0–3] settings must be chosen such that the resulting SYSCLK (bus)
frequency, CPU (core) frequency, and PLL (VCO) frequency do not exceed their respective maximum or minimum
operating frequencies. Refer to the PLL_CFG[0–3] signal description in Table 17,” for valid PLL_CFG[0–3] settings
2. Rise and fall times measurements are now specified in terms of slew rates, rather than time to account for selectable
I/O bus interface levels. The minimum slew rate of 1v/ns is equivalent to a 2ns maximum rise/fall time measured at
0.4v and 2.4v or a rise/fall time of 1ns measured at 0.4v to 1.4v.
3. Timing is guaranteed by design and characterization.
4. This represents total input jitter - short term and long term combined and is guaranteed by design.
5. Relock timing is guaranteed by design and characterization. PLL-relock time is the maximum amount of time
required for PLL lock after a stable Vdd and SYSCLK are reached during the power-on reset sequence. This specification also applies when the PLL has been disabled and subsequently re-enabled during sleep mode. Also note
that HRESET must be held asserted for a minimum of 255 bus clocks after the PLL-relock time during the power-on
reset sequence.
25/48
Figure 10 provides the SYSCLK input timing diagram.
SYSCLK
VM
VM
VM
KVIH
KVIL
tKHKL
tKR
tKF
tSYSCLK
VM = Midpoint Voltage (OVDD/2)
Figure 10 : SYSCLK Input Timing Diagram
4.2.2. Processor Bus AC Specifications
Table 11 provides the processor bus AC timing specifications for the PC755B as defined in Figure 11 and Figure 13 . Timing specifications for the L2 bus are provided in Section 4.2.1., “ L2 Clock AC Specifications.
Table 11. Processor Bus Mode Selection AC Timing Specifications1
At Vdd=AVdd=2.0V 100mV; -55 v Tj v +125 oC, OVdd = 3.3V 165mV and OVdd = 1.8V d100mV and OVdd = 2.0V100mV
Parameter
Symbols2
300, 350, 400 MHz
Min
Unit
Notes
Max
Mode select input setup to HRESET
tMVRH
8
—
tsysclk
3,4,5,6,7
HRESET to mode select input hold
tMXRH
∞
—
ns
3,4,6,7,8
Notes:
1. All input specifications are measured from the midpoint of the signal in question to the midpoint of the rising edge of
the input SYSCLK. All output specifications are measured from the midpoint of the rising edge of SYSCLK to the midpoint of the signal in question. All output timings assume a purely resistive 50 ohm load (See Figure 11). Input and
output timings are measured at the pin; time-of-flight delays must be added for trace lengths, vias, and connectors
in the system.
2. he symbology used for timing specifications herein follows the pattern of t(signal)(state)(reference)(state) for inputs and
t(reference)(state)(signal)(state) for outputs. For example, tIVKH symbolizes the time input signals (I) reach the valid state
(V) relative to the SYSCLK reference (K) going to the high(H) state or input setup time. And tKHOV symbolizes the time
from SYSCLK(K) going high(H) until outputs (O) are valid (V) or output valid time. Input hold time can be read as the
time that the input signal (I) went invalid (X) with respect to the rising clock edge (KH) - note the position of the reference
and its state for inputs -and output hold time can be read as the time from the rising edge (KH) until the output went
invalid (OX). For additional explanation of AC timing specifications in Motorola PowerPC microprocessors, see the
application note “Understanding AC Timing Specifications for PowerPC Microprocessors.”
3. The setup and hold time is with respect to the rising edge of HRESET (see Figure 11).
4. This specification is for configuration mode select only. Also note that the HRESET must be held asserted for a minimum of 255 bus clocks after the PLL re-lock time during the power-on reset sequence.
5. tsysclk is the period of the external clock (SYSCLK) in nanoseconds (ns). The numbers given in the table must be multiplied by the period of SYSCLK to compute the actual time duration (in nanoseconds) of the parameter in question.
6. Mode select signals are BVSEL, L2VSEL, PLL_CFG[0-3]
7. Guaranteed by design and characterization.
8. Bus mode select pins must remain stable during operation. Changing the logic states of BVSEL or L2VSEL during
operation will cause the bus mode voltage selection to change. Changing the logic states of the PLL_CFG pins during
operation will cause the PLL division ratio selection to change. Both of these conditions are considered outside the
specification and are not supported. Once HRESET is negated the states of the bus mode selection pins must remain
stable.
26/48
PC755B/745B
PC755B/745B
Figure 11 provides the mode select input timing diagram for the PC755B.
VM
HRESET
tMVRH
tMXRH
MODE SIGNALS
VM = Midpoint Voltage (OVDD/2)
Figure 11 : Mode Input Timing Diagram
Figure 12 provides the AC test load for the PC755B.
OUTPUT
OVdd/2
Z0 = 50 Ω
RL = 5 Ω
Figure 12 : AC Test Load
Table 12. Processor Bus AC Timing Specifications
At Vdd=AVdd=2.0V 100mV; -55
Tj +125 oC, OVdd = 3.3V
165mV and OVdd = 1.8V 100mV and OVdd = 2.0V 100mV
Parameter
Symbols
300, 350, 400 MHz
Min
Unit
Notes
Max
Setup Times: All Inputs
tIVKH
2.5
—
ns
Input Hold Times: All Inputs
tIXKH
0.6
—
ns
Valid Times: All Outputs
tKHOV
—
4.5
ns
Output Hold Times: All Outputs
tKHOX
1.0
—
ns
SYSCLK to Output Enable
tKHOE
0.5
—
ns
4
SYSCLK to Output High Impedance (all except ABB, ARTRY, DBB)
tKHOZ
—
6.0
ns
4
SYSCLK to ABB, DBB High Impedance after precharge
tKHABPZ
—
1.0
tsysclk
Maximum Delay to ARTRY Precharge
tKHARP
—
1
tsysclk
1,3,4
SYSCLK to ARTRY High Impedance After Precharge
tKHARPZ
—
2
tsysclk
1,3,4
1,2,4
Notes:
1. tsysclk is the period of the external clock (SYSCLK) in nanoseconds (ns). The numbers given in the table must be multiplied by the
period of SYSCLK to compute the actual time duration (in nanoseconds) of the parameter in question.
2. Per the 60x bus protocol, TS, ABB and DBB are driven only by the currently active bus master. They are asserted low then precharged high before returning to high-Z as shown in Figure 13. The nominal precharge width for TS, ABB or DBB is 0.5* tSYSCLK,
i.e. less than the minimum tSYSCLK period, to ensure that another master asserting TS, ABB, or DBB on the following clock will not
contend with the precharge. Output valid and output hold timing is tested for the signal asserted. Output valid time is tested for precharge.The high-Z behavior is guaranteed by design.
3. Per the 60x bus protocol, ARTRY can be driven by multiple bus masters through the clock period immediately following AACK. Bus
contention is not an issue since any master asserting ARTRY will be driving it low. Any master asserting it low in the first clock following AACK will then go to high-Z for one clock before precharging it high during the second cycle after the assertion of AACK. The
nominal precharge width for ARTRY is 1.0 tsysclk; i.e. it should be high-Z as shown in Figure 12 before the first opportunity for another
master to assert ARTRY. Output valid and output hold timing is tested for the signal asserted. Output valid time is tested for precharge.The high-Z and precharge behavior is guaranteed by design.
4. Guaranteed by design and characterization.
27/48
Figure 13 provides the input/output timing diagram for the PC755B.
SYSCLK
VM
VM
VM
tIXKH
tIVKH
ALL INPUTS
tKHOE
ALL OUTPUTS
(Except TS, ABB,
ARTRY, DBB)
tKHOV
tKHOZ
tKHOX
tKHABPZ
tKHOV
tKHOZ
tKHOX
tKHOV
TS,ABB,DBB
tKHARPZ
tKHOV
tKHOV
tKHARP
tKHOX
ARTRY
VM = Midpoint Voltage (OVDD/2 or Vin/2)
Figure 13 : Input/Output Timing Diagram
4.2.3. L2 Clock AC Specifications
The L2CLK frequency is programmed by the L2 Configuration Register (L2CR[4:6]) core-to-L2 divisor ratio. See Table 13 for example
core and L2 frequencies at various divisors. Table 13 provides the potential range of L2CLK output AC timing specifications as defined
in Figure 14.
The minimum L2CLK frequency of Table 13 is specified by the maximum delay of the internal DLL. The variable-tap DLL introduces up
to a full clock period delay in the L2CLKOUTA, L2CLKOUTB, and L2SYNC_OUT signals so that the returning L2SYNC_IN signal is
phase aligned with the next core clock (divided by the L2 divisor ratio). Do not choose a core-to-L2 divisor which results in an L2
frequency below this minimum, or the L2CLKOUT signals provided for SRAM clocking will not be phase aligned with the PC755B core
clock at the SRAMs.
The maximum L2CLK frequency shown in Table 13 is the core frequency divided by one. Very few L2 SRAM designs will be able to
operate in this mode. Most designs will select a greater core-to-L2 divisor to provide a longer L2CLK period for read and write access
to the L2 SRAMs. The maximum L2CLK frequency for any application of the PC755B will be a function of the AC timings of the
PC755B, the AC timings for the SRAM, bus loading, and printed circuit board trace length.
Motorola is similarly limited by system constraints and cannot perform tests of the L2 interface on a socketed part on a functional tester
at the maximum frequencies of Table 13. Therefore functional operation and AC timing information are tested at core-to-L2 divisors of
2 or greater. Functionality of core-to-L2 divisors of 1 or 1.5 is verified at less than maximum rated frequencies.
L2 input and output signals are latched or enabled respectively by the internal L2CLK (which is SYSCLK multiplied up to the core
frequency and divided down to the L2CLK frequency). In other words, the AC timings of Table 14 and Table 15 are entirely independent of L2SYNC_IN. In a closed loop system, where L2SYNC_IN is driven through the board trace by L2SYNC_OUT, L2SYNC_IN
only controls the output phase of L2CLKOUTA and L2CLKOUTB which are used to latch or enable data at the SRAMs. However,
since in a closed loop system L2SYNC_IN is held in phase alignment with the internal L2CLK, the signals of Table 14 and Table 15 are
referenced to this signal rather than the not-externally-visible internal L2CLK. During manufacturing test, these times are actually
measured relative to SYSCLK.
The L2SYNC_OUT signal is intended to be routed halfway out to the SRAMs and then returned to the L2SYNC_IN input of the
PC755B to synchronize L2CLKOUT at the SRAM with the processor’s internal clock. L2CLKOUT at the SRAM can be offset forward
or backward in time by shortening or lengthening the routing of L2SYNC_OUT to L2SYNC_IN. See Motorola Application Note
AN179/D “PowerPC Backside L2 Timing Analysis for the PCB Design Engineer.”
The L2CLKOUTA and L2CLKOUTB signals should not have more than two loads.
28/48
PC755B/745B
PC755B/745B
Table 13. L2CLK Output AC Timing Specification
At Vdd=AVdd=2.0V 100mV; -55
Tj
+125 oC, OVdd = 3.3V 165mV and OVdd = 1.8V 100mV and OVdd = 2.0V 100mV
Parameter
Symbol
300,350,400 MHz
Min
Unit
Notes
Max
L2CLK frequency
f L2CLK
80
400
MHz
L2CLK cycle time
t L2CLK
2,5
12.5
ns
L2CLK duty cycle
tCHCL/tL2CLK
50
1,4
%
2,7
Internal DLL-relock time
640
—
L2CLK
3,7
DLL capture window
0
10
ns
5,7
50
ps
6,7
150
ps
6,7
L2CLKOUT output-to-output skew
L2CLKOUT output jitter
tL2CSKW
Notes:
1. L2CLK outputs are L2CLK_OUTA, L2CLK_OUTB, L2CLK_OUT and L2SYNC_OUT pins. The L2CLK frequency to core frequency settings must be chosen such that the resulting L2CLK frequency and core frequency do not exceed their respective
maximum or minimum operating frequencies. The maximum L2LCK frequency will be system dependent. L2CLK_OUTA and
L2CLK_OUTB must have equal loading.
2. The nominal duty cycle of the L2CLK is 50% measured at midpoint voltage.
3. The DLL re-lock time is specified in terms of L2CLKs. The number in the table must be multiplied by the period of L2CLK to compute the actual time duration in nanoseconds. Re-lock timing is guaranteed by design and characterization.
4. The L2CR[L2SL] bit should be set for L2CLK frequencies less than 110 MHz. This adds more delay to each tap of the DLL.
5. Allowable skew between L2SYNC_OUT and L2SYNC_IN.
6. This output jitter number represents the maximum delay of one tap forward or one tap back from the current DLL tap as the phase
comparator seeks to minimize the phase difference between L2SYNC_IN and the internal L2CLK. This number must be comprehended in the L2 timing analysis. The input jitter on SYSCLK affects L2CLKOUT and the L2 address/data/control signals equally
and therefore is already comprehended in the AC timing and does not have to be considered in the L2 timing analysis.
7. Guaranteed by design and characterization.
The L2CLK_OUT timing diagram is shown in Figure 14.
29/48
L2 Single–Ended Clock Mode
tL2CR
tL2CLK
tCHCL
L2CLK_OUTA
L2CLK_OUTB
VM
VM
VM
VM
VM
VM
tL2CF
VM
tL2CSKW
L2SYNC_OUT
VM
VM
VM
L2 Differential Clock Mode
L2CLK_OUTB
tL2CLK
tCHCL
L2CLK_OUTA
VM
VM
VM
L2SYNC_OUT
VM
VM
VM
VM = Midpoint Voltage (L2OVdd/2)
Figure 14 : L2CLK_OUT Output Timing Diagram
30/48
PC755B/745B
VM
PC755B/745B
4.2.4. L2 Bus Input AC Specifications
Table 14 provides the L2 bus interface AC timing specifications for the PC755B as defined in Figure 15 and Figure 16 for the loading
conditions described in Figure 17.
Table 14. L2 Bus Interface AC Timing Specifications
At Vdd=AVdd=2.0V 100mV; -55
Tj
+125 oC, OVdd = 3.3V 165mV and OVdd = 1.8V 100mV and OVdd = 2.0V 100mV
Parameter
Symbol
300 MHz
Min
L2SYNC_IN rise and fall time
tL2CR&
Max
350 MHz
Min
Max
400 MHz
Min
Unit
Notes
Max
—
1.0
—
1.0
—
1.0
ns
1
tL2CF
Setup Times: Data and parity
tDVL2CH
1.5
—
1.5
—
1.4
—
ns
2
Input Hold Times: Data and parity
tDXL2CH
0.5
—
0.5
—
0.5
—
ns
2
Valid Times:
tL2CHOV
ns
3,4
ns
3
ns
3,5
All outputs when L2CR[14-15] = 00
–
3.6
–
3.6
–
3.6
All outputs when L2CR[14-15] = 01
–
3.8
–
3.8
–
3.8
All outputs when L2CR[14-15] = 10
–
4.0
–
4.0
–
4.0
4.2
–
4.2
–
4.2
All outputs when L2CR[14-15] = 11
Output Hold Times
tL2CHOX
All outputs when L2CR[14-15] = 00
0.5
–
0.5
–
0.5
–
All outputs when L2CR[14-15] = 01
0.7
–
0.7
–
0.7
–
All outputs when L2CR[14-15] = 10
0.9
–
0.9
–
0.9
–
All outputs when L2CR[14-15] = 11
1.1
–
1.1
–
1.1
–
L2SYNC_IN to high impedance:
tL2CHOZ
All outputs when L2CR[14-15] = 00
–
3.5
–
3.5
–
3.5
All outputs when L2CR[14-15] = 01
–
4.0
–
4.0
–
4.0
All outputs when L2CR[14-15] = 10
–
4.2
–
4.2
–
4.2
All outputs when L2CR[14-15] = 11
–
4.5
–
4.5
–
4.5
Notes:
1. Rise and fall times for the L2SYNC_IN input are measured from 20% to 80% of L2OVdd.
2. All input specifications are measured from the midpoint of the signal in question to the midpoint voltage of the rising edge of
the input L2SYNC_IN (see Figure 15). Input timings are measured at the pins.
3. All output specifications are measured from the midpoint voltage of the rising edge of L2SYNC_IN to the midpoint of the signal
in question. The output timings are measured at the pins. All output timings assume a purely resistive 50 ohm load (See
Figure 16 ).
4. he outputs are valid for both single-ended and differential L2CLK modes. For pipelined registered synchronous burst RAMs,
L2CR[14–15] = 01 or 10 is recommended. For pipelined late-write synchronous burst SRAMs, L2CR[14–15] = 11 is recommended.
5. Guaranteed by design and characterization.
31/48
Figure 15 shows the L2 bus input timing diagrams for the PC755B.
tL2CR
L2SYNC_IN
tL2CF
VM
tDVL2CH
tDXL2CH
L2 DATA AND DATA
PARITY INPUTS
VM = Midpoint Voltage (L2OVDD/2)
Figure 15 : L2 Bus Input Timing Diagrams
Figure 16 shows the L2 bus output timing diagrams for the PC755B.
L2SYNC_IN
VM
VM
tL2CHOV
tL2CHOX
ALL OUTPUTS
tL2CHOZ
L2DATA BUS
VM = Midpoint Voltage (L2OVDD/2)
Figure 16 : L2 Bus Output Timing Diagrams
Figure 17 provides the AC test load for L2 interface of the PC755B.
OUTPUT
L2OVdd/2
Z0 = 50 Ω
RL = 50 Ω
Figure 17 : AC Test Load for the L2 Interface
32/48
PC755B/745B
PC755B/745B
4.2.5. IEEE 1149.1 AC Timing Specifications
4.2.5.1. Timing Specifications
Table 15 provides the IEEE 1149.1 (JTAG) AC timing specifications as defined in Figure 18, Figure 19, Figure 20, and Figure 21.
Table 15. JTAG AC Timing Specifications (Independent of SYSCLK)1
At recommended operating conditions (See Table 5 )
Parameter
Symbol
Min
Max
Unit
TCK frequency of operation
fTCLK
0
33.3
MHz
TCK cycle time
tTCLK
30
—
ns
TCK clock pulse width measured at 1.4V
tJHJL
15
—
ns
TCK rise and fall times
tJR & tJF
0
2
ns
TRST assert time
tTRST
25
—
ns
Input Setup Times:
Notes
2
ns
Boundary-scan data tDVJH
4
—
TMS, TDI t IVJH
0
—
15
—
12
—
3
Input Hold Times:
ns
Boundary-scan data tDXJH
TMS, TDI tIXJH
3
Valid Times:
ns
Boundary-scan data tJLDV
—
4
TDO t JLOV
—
4
Boundary-scan data tJLDH
20
—
TDO tJLOH
12
—
4
Output Hold Times:
ns
4
TCK to output high impedance:
ns
Boundary-scan data t JLDZ
3
19
TDO tJLOZ
3
9
4,5
Notes:
1. All outputs are measured from the midpoint voltage of the falling/rising edge of TCLK to the midpoint of the signal
in question. The output timings are measured at the pins. All output timings assume a purely resistive 50 ohm
load (See Figure 18 ). Time-of-flight delays must be added for trace lengths, vias, and connectors in the system.
2. TRST is an asynchronous level sensitive signal. The setup time is for test purposes only.
3. Non-JTAG signal input timing with respect to TCK.
4. Non-JTAG signal output timing with respect to TCK.
5. Guaranteed by design and characterization.
Figure 18 provides the AC test load for TDO and the boundary-scan outputs of the PC755B.
OUTPUT
Z0 = 50 Ω
OVdd/2
RL = 50 Ω
Figure 18 : ALTERNATE AC Test Load for the JTAG Interface
33/48
Figure 19 provides the JTAG clock input timing diagram.
TCLK
VM
VM
VM
tJHJL
tJR
tJF
tTCLK
VM = Midpoiont Voltage (0VDD/2)
Figure 19 : JTAG Clock Input Timing Diagram
Figure 20 provides the TRST timing diagram.
TRST
VM
VM
tTRST
VM = Midpoint Voltage (OVDD/2)
Figure 20 : TRST Timing Diagram
Figure 21 provides the boundary-scan timing diagram.
TCK
VM
VM
tDVJH
tDXJH
BOUNDARY
DATA INPUTS
INPUT
DATA VALID
tJLDV
tJLDH
BOUNDARY
DATA OUTPUTS
OUTPUT
DATA
VALID
tJLDZ
BOUNDARY
DATA OUTPUTS
OUTPUT DATA VALID
VM = Midpoint Voltage (OVDD/2)
Figure 21 : Boundary-Scan Timing Diagram
34/48
PC755B/745B
PC755B/745B
Figure 22 provides the test access port timing diagram.
TCK
VM
VM
tIVJH
tIXJH
INPUT
DATA VALID
TDI, TMS
tJLOV
tJLOH
OUTPUT
DATA
VALID
TDO
tJLOZ
TDO
OUTPUT DATA VALID
VM = Midpoint Voltage (OVDD/2)
Figure 22 : Test Access Port Timing Diagram
4.2.5.2. JTAG Configuration Signals
Boundary scan testing is enabled through the JTAG interface signals. The TRST signal is optional in the IEEE 1149.1 specification
but is provided on all PowerPC implementations. While it is possible to force the TAP controller to the reset state using only the TCK
and TMS signals, more reliable power-on reset performance will be obtained if the TRST signal is asserted during power-on reset.
Since the JTAG interface is also used for accessing the common on-chip processor (COP) function of PowerPC processors, simply
tying TRST to HRESET isn’t practical.
The common on-chip processor (COP) function of PowerPC processors allows a remote computer system (typically a PC with dedicated hardware and debugging software) to access and control the internal operations of the processor. The COP interface connects
primarily through the JTAG port of the processor, with some additional status monitoring signals. The COP port requires the ability to
independently assert HRESET or TRST in order to fully control the processor. If the target system has independent reset sources,
such as voltage monitors, watchdog timers, power supply failures, or push-button switches, then the COP reset signals must be
merged into these signals with logic.
The arrangement shown in Figure 23 allows the COP to independently assert HRESET or TRST, while insuring that the target can
drive HRESET as well. The pull-down resistor on TRST ensures that the JTAG scan chain is initialized during power-on if a JTAG
interface cable is not attached; if it is, it is responsible for driving TRST when needed.
Figure 23 shows the suggested TRST connection.
PC755B
HRESET
HRESET
From Target
Board
Sources
QACK
QACK
TRST
2KW
2KW
COP Header
Figure 23 : Suggested TRST Connection
35/48
The COP header shown in Figure 24 adds many benefits—breakpoints, watchpoints, register and memory examination/modification
and other standard debugger features are possible through this interface – and can be as inexpensive as an unpopulated footprint for
a header to be added when needed.
System design information
The COP interface has a standard header for connection to the target system, based on the 0.025” square-post 0.100” centered
header assembly (often called a “Berg” header). The connector typically has pin 14 removed as a connector key.
CKSTP_OUT
HRESET
SRESET
TMS
TCK
RUN/STOP
TDI
TDO
15
13
11
9
7
5
3
1
16
KEY
No pin
12
10
8
6
4
2
TRST
QACK
Figure 24 shows the COP connector diagram.
VDD_SENSE
CHKSTP_IN
Ground
TOP VIEW
Pins 10, 12 and 14 are no–connects.
Pin 14 is not physically present
Figure 24 : COP Connector Diagram
There is no standardized way to number the COP header shown in Figure 24; consequently, many different pin numbers have been
observed from emulator vendors. Some are numbered top-to-bottom then left-to-right, while others use left-to-right then top-to-bottom, while still others number the pins counter clockwise from pin one (as with an IC). Regardless of the numbering, the signal placement recommended in Figure 24 is common to all known emulators.
The QACK signal shown in Table 15 is usually hooked up to the PCI bridge chip in a system and is an input to the PC755B informing it
that it can go into the quiescent state. Under normal operation this occurs during a low power mode selection. In order for COP to work
the PC755B must see this signal asserted (pulled down). While shown on the COP header, not all emulator products drive this signal.
To preserve correct power down operation, QACK should be merged so that it also can be driven by the PCI bridge.
36/48
PC755B/745B
PC755B/745B
Table 16 shows the pin definitions.
Table 16. COP Pin Definitions
Pins
Signal
Connection
Special Notes
1
TDO
TDO
2
QACK
QACK
3
TDI
TDI
4
TRST
TRST
Add 2K pulldown to ground. Must be merged with on-board TRST, if any. See
Figure 23.
5
RUN/STOP
No Connect
Used on 604e; leave no-connect for all other processors.
6
VDD_SENSE
VDD
Add 2K pullup to OVDD (for short circuit limiting protection only).
7
TCK
TCK
8
CKSTP_IN
CKSTP_IN
9
TMS
TMS
10
N/A
11
SRESET
12
N/A
13
HRESET
14
N/A
15
CKSTP_OUT
CKSTP_OUT
16
Ground
Digital Ground
Add 2K pulldown to ground. Must be merged with on-board QACK, if any.
Optional. Add 10K pullup to OVDD. Used on several emulator products. Useful for
checkstopping the processor from a logic analyzer of other external trigger.
SRESET
Merge with on-board SRESET, if any.
HRESET
Merge with on-board HRESET.
Key location; pin should be removed.
Add 10K pullup to OVDD.
5. PREPARATION FOR DELIVERY
5.1. Packaging
Microcircuits are prepared for delivery in accordance with MIL-PRF-38535 .
5.2. Certificate of compliance
TCS offers a certificate of compliances with each shipment of parts, affirming the products are in compliance either with MIL-PRF-883
and guarantiyng the parameters not tested at temperature extremes for the entire temperature range.
6. HANDLING
MOS devices must be handled with certain precautions to avoid damage due to accumulation of static charge. Input protection
devices have been designed in the chip to minimize the effect of static buildup. However, the following handling practices are recommended:
a) Devices should be handled on benches with conductive and grounded surfaces.
b) Ground test equipment, tools and operator.
c) Do not handle devices by the leads.
d) Store devices in conductive foam or carriers.
e) Avoid use of plastic, rubber, or silk in MOS areas.
f) Maintain relative humidity above 50 percent if practical.
g) For CI-CGA packages, use specific tray to take care of the highest heigth of the package compared with the normal CBGA.
37/48
7. PACKAGE MECHANICAL DATA
The following sections provide the package parameters and mechanical dimensions for the PC745B, 255 PBGA package as well as
the PC755B, 360 CBGA and PBGA packages. While both the PC755B plastic and the ceramic packages are described here, both
packages are not guaranteed to be available at the same time. All new designs should allow for either ceramic or plastic BGA packages for this device. For more information on designing a common footprint for both plastic and ceramic package types, please contact your local Motorola sales office.
7.1. Parameters for the PC745B
7.1.1. Package Parameters for the PC745B PBGA
The package parameters are as provided in the following list. The package type is 21 x 21 mm, 255-lead plastic ball grid
array (PBGA)
Package outline
21 x 21 mm
Interconnects
255 (16 x 16 ball array - 1
Pitch
1.27 mm (50 mil)
Minimum module height
2.25 mm
Maximum module height 2.80 mm
Ball diameter (typical)
0.75 mm (29.5 mil)
38/48
PC755B/745B
PC755B/745B
7.1.2. Mechanical Dimensions of the PC745B PBGA package
Figure 25 provides the mechanical dimensions and bottom surface nomenclature of the PC745B, 255 PBGA package.
0.2
D
A
A1 CORNER
C
NOTES:
A. DIMENSIONING AND TOLERANCING
PER ASME Y14.5M, 1994.
B. DIMENSIONS IN MILLIMETERS.
C. TOP SIDE A1 CORNER INDEX IS A
METALIZED FEATURE WITH VARIOUS
SHAPES. BOTTOM SIDE A1 CORNER IS
DESIGNATED WITH A BALL MISSING
FROM THE ARRAY.
D. CAPACITOR PADS MAY BE
UNPOPULATED.
0.2 C
E
2X
0.2
B
Millimeters
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
T
R
P
N
M
L
K
J
H
G
F
E
D
C
B
A
M
DIM
Min
Max
A
2.25
2.80
A1
0.50
0.70
A2
1.00
1.20
b
0.60
0.90
D
21.00 BSC
E
21.00 BSC
e
1.27 BSC
A2
A1
A
e
255X
b
0.3 C A B
0.15 C
Figure 25 : Mechanical Dimensions and Bottom Surface Nomenclature of the PC745B PBGA
39/48
7.2. Parameters for the PC755B PBGA
7.2.1. Package parameter for the PC755B PBGA
The package parameters are as provided in the following list. The package type is 25 x 25 mm, 360-lead plastic ball grid array (PBGA).
Package outline
Interconnects
Pitch
25 x 25 mm
360 (19 x 19 ball array - 1)
1.27 mm (50 mil)
Minimum module height
2.22 mm
Maximum module height
2.77 mm
Ball diameter
0.75 mm (29.5 mil)
7.2.2. Mechanical Dimensions of the PC755B PBGA
Figure 26 provides the mechanical dimensions and bottom surface nomenclature of the PC755B, 360 PBGA package.
2X
0.2
D
A
A1 CORNER
C
0.2 C
NOTES:
A. DIMENSIONING AND TOLERANCING PER
ASME Y14.5M, 1994.
B. DIMENSIONS IN MILLIMETERS.
C. TOP SIDE A1 CORNER INDEX IS A
METALIZED FEATURE WITH VARIOUS
SHAPES. BOTTOM SIDE A1 CORNER IS
DESIGNATED WITH A BALL MISSING
FROM THE ARRAY.
E
2X
0.2
Millimeters
B
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
W
V
U
T
R
P
N
M
L
K
J
H
G
F
E
D
C
B
A
M
DIM
Min
Max
A
2.22
2.77
A1
0.50
0.70
A2
1.00
1.20
b
0.60
0.90
D
25.00 BSC
E
25.00 BSC
e
1.27 BSC
A2
A1
A
e
360X
b
0.3 C A B
0.15 C
Figure 26 : Mechanical Dimensions and Bottom Surface Nomenclature of the PC755B PBGA
40/48
PC755B/745B
PC755B/745B
8. CLOCK RELATIONSHIPS CHOICE
The PC755B’s PLL is configured by the PLL_CFG[0–3] signals. For a given SYSCLK (bus) frequency, the PLL configuration signals
set the internal CPU and VCO frequency of operation. The PLL configuration for the PC755B is shown in Figure 27 for example frequencies.
Table 17. PC755B Microprocessor PLL Configuration
PLL_CFG
[0–3]
Example Bus-to-Core Frequency in MHz (VCO Frequency in MHz)
Bus-to-Core
Multiplier
Core-to
VCO Multiplier
Bus
33 MHz
Bus
50 MHz
Bus
66 MHz
Bus
75 MHz
Bus
80 MHz
Bus
100 MHz
0100
2x
2x
—
—
—
—
—
200
(400)
1000
3x
2x
—
—
200
(400)
225
(450)
240
(480)
300
(600)
1110
3.5x
2x
—
—
233
(466)
263
(525)
280
(560)
350
(700)
1010
4x
2x
—
200
(400)
266
(533)
300
(600)
320
(640)
400
(800)
0111
4.5x
2x
—
225
(450)
300
(600)
338
(675)
360
(720)
—
1011
5x
2x
—
250
(500)
333
(666)
375
(750)
400
(800)
—
1001
5.5x
2x
—
275
(550)
366
(733)
—
—
—
1101
6x
2x
200
(400)
300
(600)
400
(800)
—
—
—
0101
6.5x
2x
216
(433)
325
(650)
—
—
—
—
0010
7x
2x
233
(466)
350
(700)
—
—
—
—
0001
7.5x
2x
250
(500)
375
(750)
—
—
—
—
1100
8x
2x
266
(533)
400
(800)
—
—
—
—
0110
10x
2x
333
(666)
—
—
—
—
—
0011
PLL off/bypass
PLL off, SYSCLK clocks core circuitry directly, 1x bus-to-core implied
1111
PLL off
PLL off, no core clocking occurs
Notes:
1. PLL_CFG[0–3] settings not listed are reserved.
2. The sample bus-to-core frequencies shown are for reference only. Some PLL configurations may select bus, core, or VCO
frequencies which are not useful, not supported, or not tested for by the PC755B; see Section 4.2.1. , “ Clock AC Specifications,”
for valid SYSCLK, core, and VCO frequencies.
3. In PLL-bypass mode, the SYSCLK input signal clocks the internal processor directly, the PLL is disabled, and the bus mode is set
for 1:1 mode operation. This mode is intended for factory use only.
Note: The AC timing specifications given in this document do not apply in PLL-bypass mode.
4. In PLL-off mode, no clocking occurs inside the PC755B regardless of the SYSCLK input.
41/48
The PC755B generates the clock for the external L2 synchronous data SRAMs by dividing the core clock frequency of the PC755B.
The divided-down clock is then phase-adjusted by an on-chip delay-lock-loop (DLL) circuit and should be routed from the PC755B to
the external RAMs. A separate clock output, L2SYNC_OUT is sent out half the distance to the SRAMs and then returned as an input to
the DLL on pin L2SYNC_IN so that the rising-edge of the clock as seen at the external RAMs can be aligned to the clocking of the
internal latches in the L2 bus interface.
The core-to-L2 frequency divisor for the L2 PLL is selected through the L2CLK bits of the L2CR register. Generally, the divisor must be
chosen according to the frequency supported by the external RAMs, the frequency of the PC755B core, and the phase adjustment
range that the L2 DLL supports. Figure 18 shows various example L2 clock frequencies that can be obtained for a given set of core
frequencies. The minimum L2 frequency target is 80MHz.
Table 18. Sample Core-to-L2 Frequencies
Core Frequency in MHz
1
1.5
2
2.5
3
250
250
166
125
100
83
266
266
177
133
106
89
275
275
183
138
110
92
300
300
200
150
120
100
325
325
217
163
130
108
333
333
222
167
133
111
350
350
233
175
140
117
366
366
244
183
146
122
375
375
250
188
150
125
400
400
266
200
160
133
Note :
The core and L2 frequencies are for reference only. Some examples may represent core
or L2 frequencies which are not useful, not supported, or not tested for by the PC755B;
see Section 4.2.1., “ L2 Clock AC Specifications,” for valid L2CLK frequencies. The
L2CR[L2SL] bit should be set for L2CLK frequencies less than 110 MHz.
42/48
PC755B/745B
PC755B/745B
9. SYSTEM DESIGN INFORMATION
9.1. PLL Power Supply Filtering
The AVdd and L2AVdd power signals are provided on the PC755B to provide power to the clock generation phase-locked loop and L2
cache delay-locked loop respectively. To ensure stability of the internal clock, the power supplied to the AVdd input signal should be
filtered of any noise in the 500kHz to 10MHz resonant frequency range of the PLL. A circuit similar to the one shown in Figure 27 using
surface mount capacitors with minimum Effective Series Inductance (ESL) is recommended. Consistent with the recommendations
of Dr. Howard Johnson in High Speed Digital Design: A Handbook of Black Magic (Prentice Hall, 1993), multiple small capacitors of
equal value are recommended over a single large value capacitor.
The circuit should be placed as close as possible to the AVdd pin to minimize noise coupled from nearby circuits. An identical but
separate circuit should be placed as close as possible to the L2AVdd pin. It is often possible to route directly from the capacitors to the
AVdd pin, which is on the periphery of the 360 BGA footprint, without the inductance of vias. The L2AVdd pin may be more difficult to
route but is proportionately less critical.
10 Ω
Vdd
AVdd (or L2AVdd)
2.2 µF
2.2 µF
Low ESL surface mount capacitors
GND
Figure 27 : PLL Power Supply Filter Circuit
9.2. Power Supply Voltage Sequencing
The notes in Figure 28 contain cautions about the sequencing of the external bus voltages and core voltage of the PC755B (when
they are different). These cautions are necessary for the long term reliability of the part. If they are violated, the ESD (Electrostatic
Discharge) protection diodes will be forward biased and excessive current can flow through these diodes. If the system power supply
design does not control the voltage sequencing, the circuit of Figure 28 can be added to meet these requirements. The MUR420
Schottky diodes of Figure 28 control the maximum potential difference between the external bus and core power supplies on power-up and the 1N5820 diodes regulate the maximum potential difference on power-down.
3.3V
2.0V
MUR420
MUR420
MUR420
1N5820
1N5820
Figure 28 : Example Voltage Sequencing Circuit
9.3. Decoupling Recommendations
Due to the PC755B’s dynamic power management feature, large address and data buses, and high operating frequencies, the
PC755B can generate transient power surges and high frequency noise in its power supply, especially while driving large capacitive
loads. This noise must be prevented from reaching other components in the PC755B system, and the PC755B itself requires a clean,
tightly regulated source of power. Therefore, it is recommended that the system designer place at least one decoupling capacitor at
each Vdd, OVdd, and L2OVdd pin of the PC755B. It is also recommended that these decoupling capacitors receive their power from
separate Vdd, (L2)OVdd and GND power planes in the PCB, utilizing short traces to minimize inductance.
These capacitors should have a value of 0.01 µF or 0.1 µF. Only ceramic SMT (surface mount technology) capacitors should be used
to minimize lead inductance, preferably 0508 or 0603 orientations where connections are made along the length of the part.
In addition, it is recommended that there be several bulk storage capacitors distributed around the PCB, feeding the Vdd, L2OVdd,
and OVdd planes, to enable quick recharging of the smaller chip capacitors. These bulk capacitors should have a low ESR (equivalent series resistance) rating to ensure the quick response time necessary. They should also be connected to the power and ground
planes through two vias to minimize inductance. Suggested bulk capacitors—100-330 µF (AVX TPS tantalum or Sanyo OSCON).
43/48
9.4. Connection Recommendations
To ensure reliable operation, it is highly recommended to connect unused inputs to an appropriate signal level through a resistor.
Unused active low inputs should be tied to OVdd. Unused active high inputs should be connected to GND. All NC (no-connect) signals
must remain unconnected.
Power and ground connections must be made to all external Vdd, OVdd, L2OVdd, and GND pins of the PC755B.
9.5. Output Buffer DC Impedance
The PC755B 60x and L2 I/O drivers are characterized over process, voltage, and temperature. To measure Z0, an external resistor is
connected from the chip pad to (L2)OVdd or GND. Then, the value of each resistor is varied until the pad voltage is (L2)OVdd/2 (See
Figure 29).
The output impedance is the average of two components, the resistances of the pull-up and pull-down devices. When Data is held
low, SW2 is closed (SW1 is open), and RN is trimmed until the voltage at the pad equals (L2)OVdd/2. RN then becomes the resistance
of the pull-down devices. When Data is held high, SW1 is closed (SW2 is open), and RP is trimmed until the voltage at the pad equals
(L2)OVdd/2. RP then becomes the resistance of the pull-up devices.
AUCUN LIEN describes the driver impedance measurement curcuit described above.
(L2)OVdd
(L2)OVdd
RN
SW2
Pad
Data
SW1
RP
OGND
Figure 29 : Driver Impedance Measurement Circuit
Alternately, the following is another method to determine the output impedence of the PC755B. A voltage source, Vforce, is connected
to the output of the PC755B as in Figure 30. Data is held low, the voltage source is set to a value that is equal to (L2)OVdd/2 and the
current sourced by Vforce is measured. The voltage drop across the pulldown device, which is equal to (L2)OVdd/2, is divided by the
measured current to determine the output impedence of the pulldown device, RN. Similarly, the impedence of the pullup device is
determined by dividing the voltage drop of the pullup, (L2)OVdd/2, by the current sank by the pullup when the data is high and Vforce is
equal to (L2)OVdd/2. This method can be employed with either empirical data from a test set up or with data from simulation models,
such as IBIS.
RP and RN are designed to be close to each other in value. Then Z0 = (RP + RN)/2.
44/48
PC755B/745B
PC755B/745B
Figure 30 describes the alternate driver impedance measurement circuit.
(L2)OVdd
BGA
Pin
Data
Vforce
OGND
Figure 30 : Alternate Driver Impedance Measurement Curcuit
Table 19 summarizes the signal impedance results. The driver impedance values were characterized at 0 C, 65 C, and 105 C. The
impedance increases with junction temperature and is relatively unaffected by bus voltage.
Table 19. Impedance Characteristics
Vdd = 2.0V, OVdd = 3.3V, Tc = 0 - 105 C
Impedance
Processor bus
L2 bus
Symbol
Unit
RN
25-36
25-36
Z0
Ohms
RP
26-39
26-39
Z0
Ohms
9.6. Pull-up Resistor Requirements
The PC755B requires high-resistive (weak: 10 KΩ) pull-up resistors on several control pins of the bus interface to maintain the control
signals in the negated state after they have been actively negated and released by the PC755B or other bus masters. These pins are
TS, ABB, ARTRY.
In addition, the PC755B has one open-drain style output that requires a pull-up resistor (weak or stronger: 4.7 KW–10 KW) if it is
used by the system. This pin is CKSTP_OUT.
During inactive periods on the bus, the address and transfer attributes may not be driven by any master and may therefore float in the
high-impedance state for relatively long periods of time. Since the PC755B must continually monitor these signals for snooping, this
float condition may cause excessive power draw by the input receivers on the PC755B or by other receivers in the system. It is recommended that these signals be pulled up through weak (10 KΩ ) pull-up resistors by the system, or that they may be otherwise driven by
the system during inactive periods of the bus. The snooped address and transfer attribute inputs are:
A[0:31], AP[0:3], TT[0:4], TBST and GBL.
The data bus input receivers are normally turned off when no read operation is in progress and therefore do not require pull-up resistors on the bus. Other data bus receivers in the system, however, may require pullups, or that those signals be otherwise driven by the
system during inactive periods by the system. The data bus signals are: DH[0:31],DL[0:31] andDP[0:7]
If 32-bit data bus mode is selected, the input receivers of the unused data and parity bits will be disabled, and their outputs will drive
logic zeros when they would otherwise normally be driven. For this mode, these pins do not require pull-up resistors, and should be left
unconnected by the system to minimize possible output switching.
If address or data parity is not used by the system, and the respective parity checking is disabled through HID0, the input receivers for
those pins are disabled, and those pins do not require pull-up resistors and should be left unconnected by the system. If all parity
generation is disabled through HID0, then all parity checking should also be disabled through HID0, and all parity pins may be left
unconnected by the system.
The L2 interface does not normally require pull-up resistors.
45/48
10. DEFINITIONS
Datasheet status
Validity
Objective specification
This datasheet contains target and goal specification
Before design phase.
for discussion with customer and application validation.
Target specification
This datasheet contains target or goal specification for
product development.
Valid during the design
phase.
Preliminary specification ∝ site
This datasheet contains preliminary data. Additional
data may be published later ; could include simulation
result.
Valid before characterization
phase.
Preliminary specification b site
This datasheet contains also characterization results.
Valid before the industrialization phase.
Product specification
This datasheet contains final product specification.
Valid for production purpose.
Limiting values
Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or more of
the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at
these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure
to limiting values for extended periods may affect device reliability.
Application information
Where application information is given, it is advisory and does not form part of the specification.
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can
reasonably be expected to result in personal injury. ATMEL-Grenoble customers using or selling these products for use in such
applications do so at their own risk and agree to fully indemnify ATMEL-Grenoble for any damages resulting from such improper use
or sale.
11. DIFFERENCES WITH COMMERCIAL PART
Commercial part
Temperature range
46/48
PC755B/745B
Tj = 0 to 105°C
Military part
Tj = -55 to 125°C
PC755B/745B
12. ORDERING INFORMATION
PC755B
M ZF
U
300 L
x
Revision level (1)
D : Rev 2.7
E : ReV 2.8
Type
(PCX755B if prototype)
Bus divider
(to be confirmed)
Temperature range : Tj
L:Any valid PLL configuration
-55, +125 °C
-40, +110 °C
M:
V:
Max internal processor speed (1)
Package :
ZF :
300
350
400
FC-PBGA (2)
: 300 MHz,
: 350 MHz,
: 400 MHz, TBC
Screening level (1) :
U
:
Upscreening Test
(1) For availability of the different versions, contact your Atmel-Grenoble sale office
(2) FC-PBGA = PBGA with Flip Chip Assembly process
Information furnished is believed to be accurate and reliable. However Atmel-Grenoble assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of Atmel-Grenoble. Specifications mentioned in this
publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. AtmelGrenoble products are not authorized for use as critical components in life support devices or systems without express written
approval from Atmel-Grenoble.
 2000 Atmel-Grenoble- Printed in France - All rights reserved.
This product is manufactured by Atmel-Grenoble- 38521 SAINT-EGREVE - FRANCE.
For further information please contact :
Atmel-Grenoble - Route Départementale 128 - B.P. 46 - 91401 ORSAY Cedex - FRANCE Phone +33 (0)1 69 33 00 00 - Fax +33 (0)1 69 33 03 21.
Internet:http://www.atmel-grenoble.com
6.
47/48