HPD Backplane read-outHPD Backplane read-out

Cdet=400pF

Q=320 fC

tr =20ns

Rate frame 300ns

tr

Q

Bari 15/01/07

tframe rate

The detector+amplifier can be approximately represented by a two dominant pole system.

The first pole is located at: flow=1/ 2Rin Cdet (for Cdet=400 pF and Rin=20 Ohm, flow= 20 Mhz)

The second one is introduced by the amplifier and must be enough spaced from the first one in order to avoid ringing.

The following closed loop situations arise:

Open loop poles

Closed loop polesBari 15/01/07

In

U1

U2

Rf

Out

gm

Ipol

Rc

R1

R2

R3

R4

Cf

Cdet

Bari 15/01/07

IN DETECTOR

OUT-

Rin1Meg

OUT+C2100n

0

Ctest10p

R18

68

R19

68

0

Cin

1n

J1

J309

J2

J309

J3

J309U1 MAX4304/MXM

+3

-2

V+7

V-4

OUT6

U2

MAX4304/MXM+

3

-2

V+7

V-4

OUT6

Q2MMBTH81

0

R1785

0

R62.2k

R14

7750

CA210u

0

C4100n

Q1MMBTH81

R103.5k

C5100nR4

470

0

C1100n

U4MAX4105/MXM

+3

-2

V+7

V-4

OUT6

J4

J201

U3MAX4105/MXM

+3

-2

V+7

V-4

OUT6

R114.7k

0

C3100n

0

R12100

R13800

R15

100R16700

R81.8k

0

CA410u

0

R73300

out

R1100

R33.3k

R210k

R9100

Rf

100k

R51.5k

Cf

3p

CA1100n

CA3100n

0

Cdet390p

INTEST

10%

90%

t1 t2

10%

90%

t1 t2

10%

90%

t1 t2

Current feedback amp., simplified schematicCurrent feedback amp., simplified schematic

Main characteristics of Main characteristics of THS3001

The THS3001 is a high-speed current-feedback operational amplifier, ideal for communication, imaging, and high-quality video applications.

This device offers a very fast 6500-V/µs slew rate, a 420-MHz bandwidth, and 40-ns settling time for large-signal applications requiring excellent transient response.

In addition, the THS3001 operates with a very low distortion of –96 dBc, making it well suited for applications such as wireless communication basestations or ultrafast ADC or DAC buffers.

Bari 15/01/07