DS3923 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – High-Speed Current Mirror

DS3923
EVALUATION KIT AVAILABLE
High-Speed Current Mirror
with Sample/Hold Output
General Description
The DS3923 high-speed current mirror integrates high-
voltage devices necessary for monitoring the burst-mode
receive power signal in avalanche photodiode (APD) bias-
ing and optical line terminal (OLT) applications. It provides
small and large gain current mirror outputs to monitor the
APD current. A sample/hold circuit with automatic gain
selection captures the sampled signal so that an external
ADC can accurately measure the signal. An adjustable
current clamp limits current through the APD. The clamp
also features an external shutdown. An integrated FET is
also provided which can be used with an external DC-DC
controller to create a high-voltage boost DC-DC converter.
The DS3923 is available in a 24-pin TQFN package and
operates over an extended temperature range of -40°C
to +95°C.
Applications
●● APD Biasing
●● GPON OLT
●● 10GPON OLT
Typical Application Circuit
Features
●● Supports -32dBm to -5dBm Optical Input Range with
±0.5dB Accuracy
●● 15V to 76V APD Bias
●● Pin Discharge Option
●● Sampling Period as Short as 300ns
●● External Capacitor Connection for Controlled RC
Time Constant of APD Voltage Filter
●● Current Clamp with Adjustable Limit and External
Shutdown with Limit Status
●● 3.5mm x 3.5mm, 24-Pin TQFN Package with
Exposed Pad
●● Two Current Mirror Outputs and Additional Small-
Signal Current Mirror Output for ADC Measurement
●● High-Voltage Switch FET for DC-DC Boost Converter
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part, refer
to www.maximintegrated.com/DS3923.related.
3.3V
4.7µH
HVD
HVG
PWM
10kΩ
DS3923
ADJUSTED FROM 55V AT -40°C TO 65V AT 95°C
MIRIN
100Ω
R1
0.1µF
C1
0.1µF
C2
330kΩ
R2
4.99kΩ
R3
GPIO[2:0] ³
ILIMS
GAIN
SENXOR
I1
200µA
0.8I1 0.2I1 0.1I1
IOUT
GPIO
(BY DEFAULT Hi-Z)
ISRC/
SHDN
ISRC
CURRENT
RLIM
R6
R7
[APD SHUTDOWN]
30kΩ
3.3V AVCC
LIMIT
3.3V
DISCHARGE
TEMP
DS4830
>300ns PULSE
OCCURS ONCE PER
100µS TO ONCE
PER 100ms
300ns
min
3.3V VCC
1.8V
GND
MIRIN
LIMIT
DUAL ^VOP
GAIN VON
SAMPLE/ _VIN
CLD
HOLD
DIFFEN
3.3V
SEN
GPIO _0V
(EDGE INTERRUPT)
[DETECT SEN EDGE] ^250µw
0V
250µw
1µw
PAPD
MIROUT
330pF
APD
TO
500pF
C3
APDV VIP1
VIP2
OPT.
OPT.
1kΩ _C4 1kΩ _C5
R4
R5
ADC [BM RSSI MONITOR,
TIA
AVERAGE RSSI,
MIRROR VOLTAGE DROP
4
DC-DC FEEDBACK]
19-6848; Rev 1; 8/14