LT6200-10 Linear Technology Corporation, LT6200-10 Datasheet - Page 21

• Manufacturer Part Number: LT6200-10
• Description: 165mhz, Rail-to-rail Input And Output, 0.95nv/rthz Low Noise, Op Amp Family
• Manufacturer: Linear Technology Corporation

APPLICATIO S I FOR ATIO
A
at 35mA, and the output transistors supply this genera-
tor current through the protection diodes.
ESD
The LT6200 has reverse-biased ESD protection diodes on
all inputs and outputs as shown in Figure 1. If these pins
are forced beyond either supply, unlimited current will
flow through these diodes. If the current is transient and
limited to 30mA or less, no damage to the device will
occur.
Noise
The noise voltage of the LT6200 is equivalent to that of a
56
desirable to keep the source and feedback resistance
at or below this value, i.e., R
R
e
tance value, the amplifier dominates the noise, but in the
resistance region between 56 and approximately 6k ,
the noise is dominated by the resistor thermal noise. As
the total resistance is further increased, beyond 6k, the
noise current multiplied by the total resistance eventually
dominates the noise.
For a complete discussion of amplifier noise, see the
LT1028 data sheet.
n
V
S
= (0.95nV)
= 1. In this photo, the input signal generator is clipping
0V
+ R
resistor, and for the lowest possible noise it is
Figure 2. V
G
//R
FB
= 56
2
S
+ (0.95nV)
= 2.5V, A
U
the total noise of the amplifier is:
U
V
2
= 1 with Large Overdrive
= 1.35nV. Below this resis-
S
+ R
W
G
//R
FB
56 . With
U
V
2.5V
V
–2.5V
CC
EE
Power Dissipation
The LT6200 combines high speed with large output cur-
rent in a small package, so there is a need to ensure that
the die’s junction temperature does not exceed 150 C. The
LT6200 is housed in a 6-lead TSOT-23 package. The
package has the V
enhance the thermal conductance when connecting to a
ground plane or a large metal trace. Metal trace and plated
through-holes can be used to spread the heat generated by
the device to the backside of the PC board. For example, on
a 3/32" FR-4 board with 2oz copper, a total of 270 square
millimeters connects to Pin 2 of the LT6200 in an TSOT-23
package will bring the thermal resistance,
135 C/W. Without extra metal trace beside the power line
connecting to the V
resistance will be around 200 C/W. More information on
thermal resistance with various metal areas connecting to
the V
Table 1. LT6200 6-Lead TSOT-23 Package
Device is mounted on topside.
Junction temperature T
temperature T
The power dissipation in the IC is the function of the supply
voltage, output voltage and the load resistance. For a given
supply voltage, the worst-case power dissipation P
occurs at the maximum quiescent supply current and at
the output voltage which is half of either supply voltage (or
the maximum swing if it is less than 1/2 the supply
voltage). P
Example: An LT6200 in TSOT-23 mounted on a 2500mm
area of PC board without any extra heat spreading plane
connected to its V
TOPSIDE (mm
COPPER AREA
T
P
J
D(MAX)
–
= T
270
100
pin is provided in Table 1.
20
0
A
+ (P
D(MAX)
= (V
2
)
A
D
S
and power dissipation P
•
• I
is given by:
–
–
JA
BOARD AREA
S(MAX)
supply pin fused to the lead frame to
–
pin to provide a heat sink, the thermal
)
LT6200-10/LT6201
(mm
pin has a thermal resistance of
2500
2500
2500
2500
LT6200/LT6200-5
J
is calculated from the ambient
2
) + (V
)
S
/2)
(JUNCTION-TO-AMBIENT)
THERMAL RESISTANCE
2
/R
L
D
135 C/W
145 C/W
160 C/W
200 C/W
as follows:
JA
, to about
21
D(MAX)
62001fa
2