
LTC6906
6
6906fc
TEST CIRCUIT
V+
GND
DIV
OUT
GRD
SET
LTC6906
EQUIVALENT CIRCUIT OF
OSCILLOSCOPE OR
FREQUENCY COUNTER PROBE
CTEST
CPROBE
RSET
0.01%
10ppm/°C
CTEST = 1/(1/5pF – 1/CPROBE)
= 7.5pF FOR A 15pF SCOPE PROBE
RPROBE
10M
SUPPLY
VOLTAGE
6906 F01
Figure 1. Test Circuit with 5pF Effective Load
EQUIVALENT INPUT AND OUTPUT CIRCUITS
Figure 2. V+ Pin
Figure 3. SET Pin
Figure 4. GRD Pin
Figure 5. DIV Pin
Figure 6. OUT Pin
6
V+
20Ω
800pF
2
GND
6906 F02
6
V+
4
SET
1k
2
GND
6906 F03
6
V+
5
GRD
200Ω
TOTAL OUTPUT
RESISTANCE
2
GND
6906 F04
6
V+
3
DIV
5M
2
GND
6906 F05
6
V+
1
OUT
300Ω
fOUT
2
GND
6906 F06