Datasheet

2 Ps/DIV
-4
-3
-2
-1
0
1
2
3
4
1 V/DIV
V
-
V
+
V
IN
V
OUT
LMH6618, LMH6619
www.ti.com SNOSAV7E –AUGUST 2007–REVISED OCTOBER 2012
APPLICATION INFORMATION
The LMH6618 and LMH6619 are based on TI’s proprietary VIP10 dielectrically isolated bipolar process. This
device family architecture features the following:
• Complimentary bipolar devices with exceptionally high f
t
(∼8 GHz) even under low supply voltage (2.7V) and
low bias current.
• Common emitter push-push output stage. This architecture allows the output to reach within millivolts of either
supply rail.
• Consistent performance from any supply voltage
(2.7V - 11V)
with little variation with supply voltage for the most
important specifications (e.g. BW, SR, I
OUT
.)
• Significant power saving compared to competitive devices on the market with similar performance.
With 3V supplies and a common mode input voltage range that extends beyond either supply rail, the LMH6618
and LMH6619 are well suited to many low voltage/low power applications. Even with 3V supplies, the −3 dB BW
(at A
V
= +1) is typically 120 MHz.
The LMH6618 and LMH6619 are designed to avoid output phase reversal. With input over-drive, the output is
kept near the supply rail (or as close to it as mandated by the closed loop gain setting and the input voltage).
Figure 62 shows the input and output voltage when the input voltage significantly exceeds the supply voltages.
Figure 62. Input and Output Shown with CMVR Exceeded
If the input voltage range is exceeded by more than a diode drop beyond either rail, the internal ESD protection
diodes will start to conduct. The current flow in these ESD diodes should be externally limited.
The LMH6618 can be shutdown by connecting the DISABLE pin to a voltage 0.5V below the supply midpoint
which will reduce the supply current to typically less than 100 µA. The DISABLE pin is “active low” and should be
connected through a resistor to V
+
for normal operation. Shutdown is guaranteed when the DISABLE pin is 0.5V
below the supply midpoint at any operating supply voltage and temperature.
In the shutdown mode, essentially all internal device biasing is turned off in order to minimize supply current flow
and the output goes into high impedance mode. During shutdown, the input stage has an equivalent circuit as
shown in Figure 63.
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Product Folder Links: LMH6618 LMH6619