HMC681LP5 Datasheet, PDF (6/10 Pages) Hittite Microwave Corporation – 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL VARIABLE GAIN AMPLIFIER w/ SERIAL CONTROL, DC - 1 GHz

HMC681LP5 / 681LP5E
v03.1010
0.5 dB LSB GaAs MMIC 6-BIT DIGITAL VARIABLE
GAIN AMPLIFIER w/ SERIAL CONTROL, DC - 1 GHz
Serial Control Interface
The HMC681LP5(E) contains a 3-wire SPI compatible digital interface (SERIN, CLK, LE). It is activated when P/S
is kept high. The 6-bit serial word must be loaded MSB first. The positive-edge sensitive CLK and LE requires
clean transitions. If mechanical switches were used, sufficient debouncing should be provided. When LE is high,
6-bit data in the serial input register is transferred to the attenuator. When LE is high CLK is masked to prevent data
transition during output loading.
For all modes of operations, gain will remain constant while LE is kept low.
12
Parameter
Typ.
Min. serial period, t_SCK
Control set-up time, t_CS
Control hold-time, t_CH
LE setup-time, t_LN
Min. LE pulse width, t_LEW
Min LE pulse spacing, t_LES
Serial clock hold-time from LE, t_CKN
Hold Time, t_PH.
Latch Enable Minimum Width, t_LEN
Setup Time, t_PS
100 ns
20 ns
20 ns
10 ns
10 ns
630 ns
10 ns
0 ns
10 ns
2 ns
Truth Table
B5
B4
16 dB 8dB
Serial Word
B3
4 dB
B2
2 dB
B1
B0
1 dB 0.5 dB
Relative
Gain
Setting
High
High
High
High
High
High
Reference
0 dB
High High High High High Low
-0.5 dB
High High High High Low High
-1 dB
High High High Low High High
-2 dB
High High Low High High High
-4 dB
High Low High High High High
-8 dB
Low High High High High High
-16 dB
Low Low Low Low Low Low -31.5 dB
Any combination of the above states will provide a relative gain
setting approximately equal to the sum of the bits selected.
For price, delivery and to place orders: Hittite Microwave Corporation, 20 Alpha Road, Chelmsford, MA 01824
Phone: [phone] Fax: [phone] Order On-line at www.hittite.com
Application Support: Phone: [phone] or [e-mail]
12 - 6