Analog Devices ADSP-2183, ADSP-2181 manual Package, 50C/W 2C/W 48C/W, 41C/W 10C/W 31C/W

ADSP-2181/ADSP-2183

ADSP-2181

ENVIRONMENTAL CONDITIONS

Ambient Temperature Rating:

TAMB = TCASE – (PD × θCA)

TCASE = Case Temperature in °C PD = Power Dissipation in W

θCA = Thermal Resistance (Case-to-Ambient)

θJA = Thermal Resistance (Junction-to-Ambient)

θJC = Thermal Resistance (Junction-to-Case)

Package		θJA	θJC		θCA
TQFP		50°C/W	2°C/W		48°C/W
PQFP		41°C/W	10°C/W		31°C/W
	1000				VDD = 5.5V
µA					VDD = 5.0V
					VDD = 4.5V
–
(LOG SCALE)	100
CURRENT	10
	0
		25	55	85
	–5

TEMPERATURE – °C

NOTES:

1.REFLECTS ADSP-2181 OPERATION IN LOWEST POWER MODE. (SEE "SYSTEM INTERFACE" CHAPTER OF THE ADSP-2100 FAMILY USER'S MANUAL FOR DETAILS.)

2.CURRENT REFLECTS DEVICE OPERATING WITH NO OUTPUT LOADS.

Figure 8. Power-Down Supply Current (Typical)

POWER DISSIPATION

To determine total power dissipation in a specific application, the following equation should be applied for each output:

C × VDD2 × f

C = load capacitance, f = output switching frequency.

Example:

In an application where external data memory is used and no other outputs are active, power dissipation is calculated as follows:

Assumptions:

•External data memory is accessed every cycle with 50% of the address pins switching.

•External data memory writes occur every other cycle with 50% of the data pins switching.

•Each address and data pin has a 10 pF total load at the pin.

•The application operates at VDD = 5.0 V and tCK = 30 ns.

Total Power Dissipation = PINT + (C × VDD2 × f )

PINT = internal power dissipation from Power vs. Frequency graph (Figure 9).

(C × VDD2 × f ) is calculated for each output:

			# of
			Pins	× C	× VDD2		× f
Address,			8	× 10 pF	× 52	V	× 33.3 MHz	=	66.6 mW
	DMS
Data Output,			9	× 10 pF	× 52	V	× 16.67 MHz	=	37.5 mW
		WR
RD			1	× 10 pF	× 52	V	× 16.67 MHz	=	4.2 mW
CLKOUT			1	× 10 pF	× 52	V	× 33.3 MHz	=	8.3 mW
									116.6 mW

Total power dissipation for this example is PINT + 116.6 mW.

	570	2181 POWER, INTERNAL
	550			VDD = 5.5V
	530					550mW
mW	510	490mW
	480
) –	450
INT
	420			VDD = 5.0V
(P
POWER	390	365mW				425mW
	360
	330			VDD = 4.5V
	300	275mW				330mW
	270
	240	29	30	31	32	33
	28						34
				1/tCK – MHz

POWER, IDLE1, 2

	95
	90		VDD = 5.5V
	85					90mW
– mW	80
	75
)		75mW
IDLE	70		VDD	= 5.0V
(P	65					70mW
POWER
	60	60mW
	55		VDD = 4.5V
	50					54mW
	45	47mW
	40
	28	29	30	31	32	33	34
			1/fCK – MHz

	75			POWER, IDLE n MODES3
	70									IDLE;
	65							70mW
mW	60
–		60mW
)	55
n
IDLE	50
(P
POWER	45
	40
								35mW		IDLE (16)
	35
		31mW
										IDLE (128)
	30
								33mW
	25		29mW
	28	29			30	31	32	33	34

1/fCK – MHz

VALID FOR ALL TEMPERATURE GRADES.

1POWER REFLECTS DEVICE OPERATING WITH NO OUTPUT LOADS.

2IDLE REFERS TO ADSP-2181 STATE OF OPERATION DURING EXECUTION OF IDLE INSTRUCTION. DEASSERTED PINS ARE DRIVEN TO EITHER VDD OR GND.

3TYPICAL POWER DISSIPATION AT 5.0V VDD DURING EXECUTION OF IDLE n

INSTRUCTION (CLOCK FREQUENCY REDUCTION).

4IDD MEASUREMENT TAKEN WITH ALL INSTRUCTIONS EXECUTING FROM INTERNAL MEMORY. 50% OF THE INSTRUCTIONS ARE MULTIFUNCTION (TYPES 1,4,5,12,13,14), 30% ARE TYPE 2 AND TYPE 6, AND 20% ARE IDLE INSTRUCTIONS.

Figure 9. Power vs. Frequency

–14– REV. 0