HMC625LP5_10 Datasheet, PDF (4/8 Pages) Hittite Microwave Corporation – 0.5 dB LSB GaAs MMIC 6-BIT DIGITAL VARIABLE GAIN AMPLIFIER, DC - 6 GHz

v09.0410
HMC625LP5 / 625LP5E
0.5 dB LSB GaAs MMIC 6-BIT DIGITAL
VARIABLE GAIN AMPLIFIER, DC - 6 GHz
Serial Control Interface
The HMC625LP5(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.
When P/S is low, 3-wire SPI interface inputs (SERIN, CLK, LE) are disabled and serial input register is loaded
asynchronously with parallel digital inputs (D0-D5). When LE is high, 6-bit parallel data is transferred to the attenuator.
For all modes of operations, the DVGA state will stay constant while LE is kept low.
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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
Timing Diagram (Latched Parallel Mode)
Parallel Mode (Direct Parallel Mode & Latched Parallel Mode)
Note: The parallel mode is enabled when P/S is set to low.
Direct Parallel Mode - The attenuation state is changed by the Control Voltage Inputs directly. The LE (Latch Enable)
must be at a logic high to control the attenuator in this manner.
Latched Parallel Mode - The attenuation state is selected using the Control Voltage Inputs and set while the LE is in
the Low state. The attenuator will not change state while LE is Low. Once all Control Voltage Inputs are at the desired
states the LE is pulsed. See timing diagram above for reference.
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]
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